security: Pin dependency versions

Too many cases of open source projects in the JS ecosystem just going wild lately

.examples/docker-compose-grafana-prometheus/README.md

@@ -0,0 +1,23 @@
+## Usage
+```console
+docker-compose up
+```
+Once you've done the above, you should be able to access the Grafana dashboard at `http://localhost:3000`.
+
+## Queries
+Gatus uses Prometheus counters.
+
+Total results per minute:
+```
+sum(rate(gatus_results_total[5m])*60) by (key)
+```
+
+Total successful results per minute:
+```
+sum(rate(gatus_results_total{success="true"}[5m])*60) by (key)
+```
+
+Total unsuccessful results per minute:
+```
+sum(rate(gatus_results_total{success="true"}[5m])*60) by (key)
+```

.examples/docker-compose-grafana-prometheus/docker-compose.yml

@@ -7,7 +7,7 @@ services:
     ports:
       - "8080:8080"
     volumes:
-      - ./config.yaml:/config/config.yaml
+      - ./config:/config
     networks:
       - metrics
 

.examples/docker-compose-grafana-prometheus/grafana/provisioning/dashboards/main.json

@@ -15,7 +15,6 @@
   "editable": true,
   "gnetId": null,
   "graphTooltip": 0,
-  "id": 2,
   "links": [],
   "panels": [
     {
@@ -24,20 +23,26 @@
       "dashLength": 10,
       "dashes": false,
       "datasource": null,
+      "description": "Number of results per minute",
       "fill": 1,
       "fillGradient": 0,
       "gridPos": {
-        "h": 14,
+        "h": 7,
         "w": 12,
         "x": 0,
         "y": 0
       },
       "id": 2,
+      "interval": "",
       "legend": {
+        "alignAsTable": false,
         "avg": false,
         "current": false,
+        "hideEmpty": false,
+        "hideZero": false,
         "max": false,
         "min": false,
+        "rightSide": false,
         "show": true,
         "total": false,
         "values": false
@@ -58,9 +63,13 @@
       "steppedLine": false,
       "targets": [
         {
-          "expr": "sum(rate(gatus_tasks[30s])) by (endpoint)",
+          "expr": "sum(rate(gatus_results_total[5m])*60) by (key)",
+          "format": "time_series",
+          "hide": false,
+          "instant": false,
           "interval": "30s",
-          "legendFormat": "{{endpoint}}",
+          "intervalFactor": 1,
+          "legendFormat": "{{key}}",
           "refId": "A"
         }
       ],
@@ -68,7 +77,7 @@
       "timeFrom": null,
       "timeRegions": [],
       "timeShift": null,
-      "title": "All tasks executed over time",
+      "title": "Total results per minute",
       "tooltip": {
         "shared": true,
         "sort": 0,
@@ -84,6 +93,7 @@
       },
       "yaxes": [
         {
+          "decimals": null,
           "format": "short",
           "label": null,
           "logBase": 1,
@@ -119,93 +129,6 @@
         "x": 12,
         "y": 0
       },
-      "id": 3,
-      "legend": {
-        "avg": false,
-        "current": false,
-        "max": false,
-        "min": false,
-        "show": true,
-        "total": false,
-        "values": false
-      },
-      "lines": true,
-      "linewidth": 1,
-      "nullPointMode": "null",
-      "options": {
-        "dataLinks": []
-      },
-      "percentage": false,
-      "pointradius": 2,
-      "points": false,
-      "renderer": "flot",
-      "seriesOverrides": [],
-      "spaceLength": 10,
-      "stack": false,
-      "steppedLine": false,
-      "targets": [
-        {
-          "expr": "sum(rate(gatus_tasks{success=\"false\"}[30s])) by (endpoint)",
-          "interval": "30s",
-          "legendFormat": "{{endpoint}}",
-          "refId": "A"
-        }
-      ],
-      "thresholds": [],
-      "timeFrom": null,
-      "timeRegions": [],
-      "timeShift": null,
-      "title": "Unsuccessful tasks",
-      "tooltip": {
-        "shared": true,
-        "sort": 0,
-        "value_type": "individual"
-      },
-      "type": "graph",
-      "xaxis": {
-        "buckets": null,
-        "mode": "time",
-        "name": null,
-        "show": true,
-        "values": []
-      },
-      "yaxes": [
-        {
-          "format": "short",
-          "label": null,
-          "logBase": 1,
-          "max": null,
-          "min": null,
-          "show": true
-        },
-        {
-          "format": "short",
-          "label": null,
-          "logBase": 1,
-          "max": null,
-          "min": null,
-          "show": true
-        }
-      ],
-      "yaxis": {
-        "align": false,
-        "alignLevel": null
-      }
-    },
-    {
-      "aliasColors": {},
-      "bars": false,
-      "dashLength": 10,
-      "dashes": false,
-      "datasource": null,
-      "fill": 1,
-      "fillGradient": 0,
-      "gridPos": {
-        "h": 7,
-        "w": 12,
-        "x": 12,
-        "y": 7
-      },
       "id": 5,
       "legend": {
         "avg": false,
@@ -232,10 +155,10 @@
       "steppedLine": false,
       "targets": [
         {
-          "expr": "sum(rate(gatus_tasks{success=\"true\"}[30s])) by (endpoint)",
+          "expr": "sum(rate(gatus_results_total{success=\"true\"}[5m])*60) by (key)",
           "instant": false,
           "interval": "30s",
-          "legendFormat": "{{endpoint}}",
+          "legendFormat": "{{key}}",
           "refId": "A"
         }
       ],
@@ -243,7 +166,183 @@
       "timeFrom": null,
       "timeRegions": [],
       "timeShift": null,
-      "title": "Successful tasks",
+      "title": "Successful results per minute",
+      "tooltip": {
+        "shared": true,
+        "sort": 0,
+        "value_type": "individual"
+      },
+      "type": "graph",
+      "xaxis": {
+        "buckets": null,
+        "mode": "time",
+        "name": null,
+        "show": true,
+        "values": []
+      },
+      "yaxes": [
+        {
+          "decimals": null,
+          "format": "short",
+          "label": null,
+          "logBase": 1,
+          "max": null,
+          "min": null,
+          "show": true
+        },
+        {
+          "format": "short",
+          "label": null,
+          "logBase": 1,
+          "max": null,
+          "min": null,
+          "show": true
+        }
+      ],
+      "yaxis": {
+        "align": false,
+        "alignLevel": null
+      }
+    },
+    {
+      "cacheTimeout": null,
+      "colorBackground": false,
+      "colorPostfix": false,
+      "colorPrefix": false,
+      "colorValue": true,
+      "colors": [
+        "#299c46",
+        "rgba(237, 129, 40, 0.89)",
+        "#d44a3a"
+      ],
+      "datasource": null,
+      "format": "none",
+      "gauge": {
+        "maxValue": 100,
+        "minValue": 0,
+        "show": false,
+        "thresholdLabels": false,
+        "thresholdMarkers": true
+      },
+      "gridPos": {
+        "h": 7,
+        "w": 12,
+        "x": 0,
+        "y": 7
+      },
+      "id": 7,
+      "interval": "",
+      "links": [],
+      "mappingType": 1,
+      "mappingTypes": [
+        {
+          "name": "value to text",
+          "value": 1
+        },
+        {
+          "name": "range to text",
+          "value": 2
+        }
+      ],
+      "maxDataPoints": 100,
+      "nullPointMode": "connected",
+      "nullText": null,
+      "options": {},
+      "postfix": "",
+      "postfixFontSize": "50%",
+      "prefix": "",
+      "prefixFontSize": "50%",
+      "rangeMaps": [
+        {
+          "from": "null",
+          "text": "N/A",
+          "to": "null"
+        }
+      ],
+      "sparkline": {
+        "fillColor": "rgba(31, 118, 189, 0.18)",
+        "full": false,
+        "lineColor": "rgb(31, 120, 193)",
+        "show": true,
+        "ymax": null,
+        "ymin": null
+      },
+      "tableColumn": "",
+      "targets": [
+        {
+          "expr": "rate(gatus_results_total{success=\"false\"}[1m])*60",
+          "format": "time_series",
+          "instant": false,
+          "intervalFactor": 1,
+          "refId": "A"
+        }
+      ],
+      "thresholds": "1,2",
+      "timeFrom": null,
+      "timeShift": null,
+      "title": "Unsuccessful results",
+      "type": "singlestat",
+      "valueFontSize": "150%",
+      "valueMaps": [
+        {
+          "op": "=",
+          "text": "N/A",
+          "value": "null"
+        }
+      ],
+      "valueName": "current"
+    },
+    {
+      "aliasColors": {},
+      "bars": false,
+      "dashLength": 10,
+      "dashes": false,
+      "datasource": null,
+      "fill": 1,
+      "fillGradient": 0,
+      "gridPos": {
+        "h": 7,
+        "w": 12,
+        "x": 12,
+        "y": 7
+      },
+      "id": 3,
+      "legend": {
+        "avg": false,
+        "current": false,
+        "max": false,
+        "min": false,
+        "show": true,
+        "total": false,
+        "values": false
+      },
+      "lines": true,
+      "linewidth": 1,
+      "nullPointMode": "null",
+      "options": {
+        "dataLinks": []
+      },
+      "percentage": false,
+      "pointradius": 2,
+      "points": false,
+      "renderer": "flot",
+      "seriesOverrides": [],
+      "spaceLength": 10,
+      "stack": false,
+      "steppedLine": false,
+      "targets": [
+        {
+          "expr": "sum(rate(gatus_results_total{success=\"false\"}[5m])*60) by (key)",
+          "interval": "30s",
+          "legendFormat": "{{key}} ",
+          "refId": "A"
+        }
+      ],
+      "thresholds": [],
+      "timeFrom": null,
+      "timeRegions": [],
+      "timeShift": null,
+      "title": "Unsuccessful results per minute",
       "tooltip": {
         "shared": true,
         "sort": 0,
@@ -289,12 +388,12 @@
     "list": []
   },
   "time": {
-    "from": "now-30m",
+    "from": "now-1h",
     "to": "now"
   },
   "timepicker": {},
   "timezone": "",
   "title": "Gatus",
   "uid": "KPI7Qj1Wk",
-  "version": 3
+  "version": 1
 }

.examples/docker-compose-mattermost/docker-compose.yml

@@ -6,7 +6,7 @@ services:
     ports:
       - "8080:8080"
     volumes:
-      - ./config.yaml:/config/config.yaml
+      - ./config:/config
     networks:
       - default
 

.examples/docker-compose-postgres-storage/docker-compose.yml

@@ -19,11 +19,11 @@ services:
     ports:
       - "8080:8080"
     volumes:
-      - ./config.yaml:/config/config.yaml
+      - ./config:/config
     networks:
       - web
     depends_on:
       - postgres
 
 networks:
-  web:
+  web:

.examples/docker-compose-sqlite-storage/docker-compose.yml

@@ -5,5 +5,5 @@ services:
     ports:
       - "8080:8080"
     volumes:
-      - ./config.yaml:/config/config.yaml
-      - ./data:/data/
+      - ./config:/config
+      - ./data:/data/

.examples/docker-compose/docker-compose.yml

@@ -5,4 +5,4 @@ services:
     ports:
       - 8080:8080
     volumes:
-      - ./config.yaml:/config/config.yaml
+      - ./config:/config

.github/codecov.yml

@@ -5,3 +5,8 @@ ignore:
 coverage:
   status:
     patch: off
+    project:
+      default:
+        target: 75%
+        threshold: null
+

.github/workflows/publish-latest.yml

@@ -9,7 +9,7 @@ jobs:
     name: Publish latest
     runs-on: ubuntu-latest
     if: ${{ github.event.workflow_run.conclusion == 'success' }}
-    timeout-minutes: 30
+    timeout-minutes: 45
     steps:
       - name: Check out code
         uses: actions/checkout@v2
@@ -27,7 +27,7 @@ jobs:
       - name: Build and push docker image
         uses: docker/build-push-action@v2
         with:
-          platforms: linux/amd64
+          platforms: linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64
           pull: true
           push: true
           tags: |

.github/workflows/publish-release.yml

@@ -6,7 +6,7 @@ jobs:
   publish-release:
     name: Publish release
     runs-on: ubuntu-latest
-    timeout-minutes: 30
+    timeout-minutes: 45
     steps:
       - name: Check out code
         uses: actions/checkout@v2

.gitignore

@@ -1,8 +1,7 @@
 .idea
 .vscode
+*.db
+*.db-shm
+*.db-wal
 gatus
-db.db
-config/config.yml
-db.db-shm
-db.db-wal
-memory.db
+config/config.yml

LICENSE

@@ -0,0 +1,202 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
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+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
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+   Copyright 2021 TwiN
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+   you may not use this file except in compliance with the License.
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+
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+
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+   See the License for the specific language governing permissions and
+   limitations under the License.
+

README.md

@@ -1,11 +1,10 @@
-![Gatus](.github/assets/logo-with-name.png)
+![Gatus](.github/assets/logo-with-dark-text.png)
 
 ![build](https://github.com/TwiN/gatus/workflows/build/badge.svg?branch=master)
 [![Go Report Card](https://goreportcard.com/badge/github.com/TwiN/gatus?)](https://goreportcard.com/report/github.com/TwiN/gatus)
 [![codecov](https://codecov.io/gh/TwiN/gatus/branch/master/graph/badge.svg)](https://codecov.io/gh/TwiN/gatus)
 [![Go version](https://img.shields.io/github/go-mod/go-version/TwiN/gatus.svg)](https://github.com/TwiN/gatus)
 [![Docker pulls](https://img.shields.io/docker/pulls/twinproduction/gatus.svg)](https://cloud.docker.com/repository/docker/twinproduction/gatus)
-[![Join Discord server](https://img.shields.io/discord/442432928614449155.svg?label=&logo=discord&logoColor=ffffff&color=7389D8&labelColor=6A7EC2)](https://discord.gg/TDfjeHmXDQ)
 [![Follow TwiN](https://img.shields.io/github/followers/TwiN?label=Follow&style=social)](https://github.com/TwiN)
 
 Gatus is a health dashboard that gives you the ability to monitor your services using HTTP, ICMP, TCP, and even DNS
@@ -25,6 +24,9 @@ docker run -p 8080:8080 --name gatus twinproduction/gatus
 For more details, see [Usage](#usage)
 </details>
 
+![Gatus dashboard conditions](.github/assets/dashboard-conditions.png)
+
+Have any feedback or want to share your good/bad experience with Gatus? Feel free to email me at [feedback@gatus.io](mailto:feedback@gatus.io)
 
 ## Table of Contents
 - [Why Gatus?](#why-gatus)
@@ -38,8 +40,11 @@ For more details, see [Usage](#usage)
   - [Client configuration](#client-configuration)
   - [Alerting](#alerting)
     - [Configuring Discord alerts](#configuring-discord-alerts)
+    - [Configuring Email alerts](#configuring-email-alerts)
+    - [Configuring Google Chat alerts](#configuring-google-chat-alerts)
     - [Configuring Mattermost alerts](#configuring-mattermost-alerts)
     - [Configuring Messagebird alerts](#configuring-messagebird-alerts)
+    - [Configuring Opsgenie alerts](#configuring-opsgenie-alerts)
     - [Configuring PagerDuty alerts](#configuring-pagerduty-alerts)
     - [Configuring Slack alerts](#configuring-slack-alerts)
     - [Configuring Teams alerts](#configuring-teams-alerts)
@@ -48,6 +53,9 @@ For more details, see [Usage](#usage)
     - [Configuring custom alerts](#configuring-custom-alerts)
     - [Setting a default alert](#setting-a-default-alert)
   - [Maintenance](#maintenance)
+  - [Security](#security)
+    - [Basic](#basic)
+    - [OIDC (ALPHA)](#oidc-alpha)
 - [Deployment](#deployment)
   - [Docker](#docker)
   - [Helm Chart](#helm-chart)
@@ -63,7 +71,6 @@ For more details, see [Usage](#usage)
   - [Monitoring an endpoint using DNS queries](#monitoring-an-endpoint-using-dns-queries)
   - [Monitoring an endpoint using STARTTLS](#monitoring-an-endpoint-using-starttls)
   - [Monitoring an endpoint using TLS](#monitoring-an-endpoint-using-tls)
-  - [Basic authentication](#basic-authentication)
   - [disable-monitoring-lock](#disable-monitoring-lock)
   - [Reloading configuration on the fly](#reloading-configuration-on-the-fly)
   - [Endpoint groups](#endpoint-groups)
@@ -87,24 +94,24 @@ Gatus, on the other hand, allows you to configure health checks for each of your
 monitor these features and potentially alert you before any clients are impacted.
 
 A sign you may want to look into Gatus is by simply asking yourself whether you'd receive an alert if your load balancer
-was to go down right now. Will any of your existing alerts by triggered? Your metrics won’t report an increase in errors
-if there’s no traffic that makes it to your applications. This puts you in a situation where your clients are the ones
+was to go down right now. Will any of your existing alerts be triggered? Your metrics won’t report an increase in errors
+if no traffic makes it to your applications. This puts you in a situation where your clients are the ones
 that will notify you about the degradation of your services rather than you reassuring them that you're working on
 fixing the issue before they even know about it.
 
 
 ## Features
-![Gatus dark mode](.github/assets/dark-mode.png)
-
 The main features of Gatus are:
 - **Highly flexible health check conditions**: While checking the response status may be enough for some use cases, Gatus goes much further and allows you to add conditions on the response time, the response body and even the IP address.
 - **Ability to use Gatus for user acceptance tests**: Thanks to the point above, you can leverage this application to create automated user acceptance tests.
 - **Very easy to configure**: Not only is the configuration designed to be as readable as possible, it's also extremely easy to add a new service or a new endpoint to monitor.
-- **Alerting**: While having a pretty visual dashboard is useful to keep track of the state of your application(s), you probably don't want to stare at it all day. Thus, notifications via Slack, Mattermost, Messagebird, PagerDuty, Twilio and Teams are supported out of the box with the ability to configure a custom alerting provider for any needs you might have, whether it be a different provider or a custom application that manages automated rollbacks.
+- **Alerting**: While having a pretty visual dashboard is useful to keep track of the state of your application(s), you probably don't want to stare at it all day. Thus, notifications via Slack, Mattermost, Messagebird, PagerDuty, Twilio, Google chat and Teams are supported out of the box with the ability to configure a custom alerting provider for any needs you might have, whether it be a different provider or a custom application that manages automated rollbacks.
 - **Metrics**
 - **Low resource consumption**: As with most Go applications, the resource footprint that this application requires is negligibly small.
-- **[Badges](#badges)**: ![Uptime 7d](https://status.twin.sh/api/v1/endpoints/core_website-external/uptimes/7d/badge.svg) ![Response time 24h](https://status.twin.sh/api/v1/endpoints/core_website-external/response-times/24h/badge.svg)
+- **[Badges](#badges)**: ![Uptime 7d](https://status.twin.sh/api/v1/endpoints/core_blog-external/uptimes/7d/badge.svg) ![Response time 24h](https://status.twin.sh/api/v1/endpoints/core_blog-external/response-times/24h/badge.svg)
+- **Dark mode**
 
+![Gatus dashboard dark mode](.github/assets/dashboard-dark.png)
 
 ## Usage
 By default, the configuration file is expected to be at `config/config.yaml`.
@@ -116,19 +123,19 @@ Here's a simple example:
 endpoints:
   - name: website                 # Name of your endpoint, can be anything
     url: "https://twin.sh/health"
-    interval: 30s                 # Duration to wait between every status check (default: 60s)
+    interval: 5m                  # Duration to wait between every status check (default: 60s)
     conditions:
       - "[STATUS] == 200"         # Status must be 200
       - "[BODY].status == UP"     # The json path "$.status" must be equal to UP
       - "[RESPONSE_TIME] < 300"   # Response time must be under 300ms
   - name: example
     url: "https://example.org/"
-    interval: 5m
+    interval: 60s
     conditions:
       - "[STATUS] == 200"
 ```
 
-This example would look like this:
+This example would look similar to this:
 
 ![Simple example](.github/assets/example.png)
 
@@ -138,105 +145,105 @@ If you want to test it locally, see [Docker](#docker).
 
 
 ## Configuration
-| Parameter                                | Description                                                                   | Default        |
-|:---------------------------------------- |:----------------------------------------------------------------------------- |:-------------- |
-| `debug`                                  | Whether to enable debug logs.                                                 | `false`        |
-| `metrics`                                | Whether to expose metrics at /metrics.                                        | `false`        |
-| `storage`                                | [Storage configuration](#storage)                                              | `{}`           |
-| `endpoints`                               | List of endpoints to monitor.                                                 | Required `[]`  |
-| `endpoints[].enabled`                     | Whether to monitor the endpoint.                                              | `true`         |
-| `endpoints[].name`                        | Name of the endpoint. Can be anything.                                        | Required `""`  |
-| `endpoints[].group`                       | Group name. Used to group multiple endpoints together on the dashboard. <br />See [Endpoint groups](#endpoint-groups). | `""`           |
-| `endpoints[].url`                         | URL to send the request to.                                                   | Required `""`  |
-| `endpoints[].method`                      | Request method.                                                               | `GET`          |
-| `endpoints[].conditions`                  | Conditions used to determine the health of the endpoint. <br />See [Conditions](#conditions). | `[]`           |
-| `endpoints[].interval`                    | Duration to wait between every status check.                                  | `60s`          |
-| `endpoints[].graphql`                     | Whether to wrap the body in a query param (`{"query":"$body"}`).              | `false`        |
-| `endpoints[].body`                        | Request body.                                                                 | `""`           |
-| `endpoints[].headers`                     | Request headers.                                                              | `{}`           |
-| `endpoints[].dns`                         | Configuration for an endpoint of type DNS. <br />See [Monitoring an endpoint using DNS queries](#monitoring-an-endpoint-using-dns-queries). | `""`           |
-| `endpoints[].dns.query-type`              | Query type (e.g. MX)                                                          | `""`           |
-| `endpoints[].dns.query-name`              | Query name (e.g. example.com)                                                 | `""`           |
-| `endpoints[].alerts[].type`               | Type of alert. <br />Valid types: `slack`, `discord`, `pagerduty`, `twilio`, `mattermost`, `messagebird`, `teams` `custom`. | Required `""`  |
-| `endpoints[].alerts[].enabled`            | Whether to enable the alert.                                                  | `false`        |
-| `endpoints[].alerts[].failure-threshold`  | Number of failures in a row needed before triggering the alert.               | `3`            |
-| `endpoints[].alerts[].success-threshold`  | Number of successes in a row before an ongoing incident is marked as resolved. | `2`           |
-| `endpoints[].alerts[].send-on-resolved`   | Whether to send a notification once a triggered alert is marked as resolved.  | `false`        |
-| `endpoints[].alerts[].description`        | Description of the alert. Will be included in the alert sent.                 | `""`           |
-| `endpoints[].client`                      | [Client configuration](#client-configuration).                                | `{}`          |
-| `endpoints[].ui`                          | UI configuration at the endpoint level.                                       | `{}`           |
-| `endpoints[].ui.hide-hostname`            | Whether to include the hostname in the result.                                | `false`        |
-| `endpoints[].ui.dont-resolve-failed-conditions` | Whether to resolve failed conditions for the UI.                        | `false`        |
-| `alerting`                               | [Alerting configuration](#alerting).                                          | `{}`           |
-| `security`                               | Security configuration.                                                       | `{}`           |
-| `security.basic`                         | Basic authentication security configuration.                                  | `{}`           |
-| `security.basic.username`                | Username for Basic authentication.                                            | Required `""`  |
-| `security.basic.password-sha512`         | Password's SHA512 hash for Basic authentication.                              | Required `""`  |
-| `disable-monitoring-lock`                | Whether to [disable the monitoring lock](#disable-monitoring-lock).           | `false`        |
-| `skip-invalid-config-update`             | Whether to ignore invalid configuration update. <br />See [Reloading configuration on the fly](#reloading-configuration-on-the-fly). | `false` |
-| `web`                                    | Web configuration.                                                            | `{}`           |
-| `web.address`                            | Address to listen on.                                                         | `0.0.0.0`      |
-| `web.port`                               | Port to listen on.                                                            | `8080`         |
-| `ui`                                     | UI configuration.                                                             | `{}`           |
-| `ui.title`                               | Title of the page.                                                            | `Health Dashboard ǀ Gatus`      |
-| `ui.logo`                                | URL to the logo to display                                                    | `""`         |
+| Parameter                                       | Description                                                                                                                                 | Default                    |
+|:------------------------------------------------|:--------------------------------------------------------------------------------------------------------------------------------------------|:---------------------------|
+| `debug`                                         | Whether to enable debug logs.                                                                                                               | `false`                    |
+| `metrics`                                       | Whether to expose metrics at /metrics.                                                                                                      | `false`                    |
+| `storage`                                       | [Storage configuration](#storage)                                                                                                           | `{}`                       |
+| `endpoints`                                     | List of endpoints to monitor.                                                                                                               | Required `[]`              |
+| `endpoints[].enabled`                           | Whether to monitor the endpoint.                                                                                                            | `true`                     |
+| `endpoints[].name`                              | Name of the endpoint. Can be anything.                                                                                                      | Required `""`              |
+| `endpoints[].group`                             | Group name. Used to group multiple endpoints together on the dashboard. <br />See [Endpoint groups](#endpoint-groups).                      | `""`                       |
+| `endpoints[].url`                               | URL to send the request to.                                                                                                                 | Required `""`              |
+| `endpoints[].method`                            | Request method.                                                                                                                             | `GET`                      |
+| `endpoints[].conditions`                        | Conditions used to determine the health of the endpoint. <br />See [Conditions](#conditions).                                               | `[]`                       |
+| `endpoints[].interval`                          | Duration to wait between every status check.                                                                                                | `60s`                      |
+| `endpoints[].graphql`                           | Whether to wrap the body in a query param (`{"query":"$body"}`).                                                                            | `false`                    |
+| `endpoints[].body`                              | Request body.                                                                                                                               | `""`                       |
+| `endpoints[].headers`                           | Request headers.                                                                                                                            | `{}`                       |
+| `endpoints[].dns`                               | Configuration for an endpoint of type DNS. <br />See [Monitoring an endpoint using DNS queries](#monitoring-an-endpoint-using-dns-queries). | `""`                       |
+| `endpoints[].dns.query-type`                    | Query type (e.g. MX)                                                                                                                        | `""`                       |
+| `endpoints[].dns.query-name`                    | Query name (e.g. example.com)                                                                                                               | `""`                       |
+| `endpoints[].alerts[].type`                     | Type of alert. <br />Valid types: `slack`, `discord`, `email`, `googlechat`, `pagerduty`, `twilio`, `mattermost`, `messagebird`, `teams` `custom`.        | Required `""`              |
+| `endpoints[].alerts[].enabled`                  | Whether to enable the alert.                                                                                                                | `false`                    |
+| `endpoints[].alerts[].failure-threshold`        | Number of failures in a row needed before triggering the alert.                                                                             | `3`                        |
+| `endpoints[].alerts[].success-threshold`        | Number of successes in a row before an ongoing incident is marked as resolved.                                                              | `2`                        |
+| `endpoints[].alerts[].send-on-resolved`         | Whether to send a notification once a triggered alert is marked as resolved.                                                                | `false`                    |
+| `endpoints[].alerts[].description`              | Description of the alert. Will be included in the alert sent.                                                                               | `""`                       |
+| `endpoints[].client`                            | [Client configuration](#client-configuration).                                                                                              | `{}`                       |
+| `endpoints[].ui`                                | UI configuration at the endpoint level.                                                                                                     | `{}`                       |
+| `endpoints[].ui.hide-hostname`                  | Whether to include the hostname in the result.                                                                                              | `false`                    |
+| `endpoints[].ui.dont-resolve-failed-conditions` | Whether to resolve failed conditions for the UI.                                                                                            | `false`                    |
+| `alerting`                                      | [Alerting configuration](#alerting).                                                                                                        | `{}`                       |
+| `security`                                      | [Security configuration](#security).                                                                                                        | `{}`                       |
+| `disable-monitoring-lock`                       | Whether to [disable the monitoring lock](#disable-monitoring-lock).                                                                         | `false`                    |
+| `skip-invalid-config-update`                    | Whether to ignore invalid configuration update. <br />See [Reloading configuration on the fly](#reloading-configuration-on-the-fly).        | `false`                    |
+| `web`                                           | Web configuration.                                                                                                                          | `{}`                       |
+| `web.address`                                   | Address to listen on.                                                                                                                       | `0.0.0.0`                  |
+| `web.port`                                      | Port to listen on.                                                                                                                          | `8080`                     |
+| `ui`                                            | UI configuration.                                                                                                                           | `{}`                       |
+| `ui.title`                                      | [Title of the document](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/title).                                                   | `Health Dashboard ǀ Gatus` |
+| `ui.header`                                     | Header at the top of the dashboard.                                                                                                         | `Health Status`            |
+| `ui.logo`                                       | URL to the logo to display.                                                                                                                 | `""`                       |
+| `ui.link`                                       | Link to open when the logo is clicked.                                                                                                      | `""`                       |
+| `maintenance`                                   | [Maintenance configuration](#maintenance).                                                                                                  | `{}`                       |
 
 
 ### Conditions
 Here are some examples of conditions you can use:
 
-| Condition                    | Description                                             | Passing values             | Failing values |
-|:-----------------------------|:------------------------------------------------------- |:-------------------------- | -------------- |
-| `[STATUS] == 200`            | Status must be equal to 200                             | 200                        | 201, 404, ...  |
-| `[STATUS] < 300`             | Status must lower than 300                              | 200, 201, 299              | 301, 302, ...  |
-| `[STATUS] <= 299`            | Status must be less than or equal to 299                | 200, 201, 299              | 301, 302, ...  |
-| `[STATUS] > 400`             | Status must be greater than 400                         | 401, 402, 403, 404         | 400, 200, ...  |
-| `[STATUS] == any(200, 429)`  | Status must be either 200 or 429                        | 200, 429                   | 201, 400, ...  |
-| `[CONNECTED] == true`        | Connection to host must've been successful              | true                       | false          |
-| `[RESPONSE_TIME] < 500`      | Response time must be below 500ms                       | 100ms, 200ms, 300ms        | 500ms, 501ms   |
-| `[IP] == 127.0.0.1`          | Target IP must be 127.0.0.1                             | 127.0.0.1                  | 0.0.0.0        |
-| `[BODY] == 1`                | The body must be equal to 1                             | 1                          | `{}`, `2`, ... |
-| `[BODY].user.name == john`   | JSONPath value of `$.user.name` is equal to `john`      | `{"user":{"name":"john"}}` |  |
-| `[BODY].data[0].id == 1`     | JSONPath value of `$.data[0].id` is equal to 1          | `{"data":[{"id":1}]}`      |  |
-| `[BODY].age == [BODY].id`    | JSONPath value of `$.age` is equal JSONPath `$.id`      | `{"age":1,"id":1}`         |  |
-| `len([BODY].data) < 5`       | Array at JSONPath `$.data` has less than 5 elements     | `{"data":[{"id":1}]}`      |  |
-| `len([BODY].name) == 8`      | String at JSONPath `$.name` has a length of 8           | `{"name":"john.doe"}`      | `{"name":"bob"}` |
-| `has([BODY].errors) == false` | JSONPath `$.errors` does not exist                     | `{"name":"john.doe"}`      | `{"errors":[]}` |
-| `has([BODY].users) == true`  | JSONPath `$.users` exists                               | `{"users":[]}`             | `{}` |
-| `[BODY].name == pat(john*)`  | String at JSONPath `$.name` matches pattern `john*`     | `{"name":"john.doe"}`      | `{"name":"bob"}` |
-| `[BODY].id == any(1, 2)`     | Value at JSONPath `$.id` is equal to `1` or `2`         | 1, 2                       | 3, 4, 5 |
-| `[CERTIFICATE_EXPIRATION] > 48h` | Certificate expiration is more than 48h away        | 49h, 50h, 123h             | 1h, 24h, ... |
+| Condition                        | Description                                         | Passing values             | Failing values   |
+|:---------------------------------|:----------------------------------------------------|:---------------------------|------------------|
+| `[STATUS] == 200`                | Status must be equal to 200                         | 200                        | 201, 404, ...    |
+| `[STATUS] < 300`                 | Status must lower than 300                          | 200, 201, 299              | 301, 302, ...    |
+| `[STATUS] <= 299`                | Status must be less than or equal to 299            | 200, 201, 299              | 301, 302, ...    |
+| `[STATUS] > 400`                 | Status must be greater than 400                     | 401, 402, 403, 404         | 400, 200, ...    |
+| `[STATUS] == any(200, 429)`      | Status must be either 200 or 429                    | 200, 429                   | 201, 400, ...    |
+| `[CONNECTED] == true`            | Connection to host must've been successful          | true                       | false            |
+| `[RESPONSE_TIME] < 500`          | Response time must be below 500ms                   | 100ms, 200ms, 300ms        | 500ms, 501ms     |
+| `[IP] == 127.0.0.1`              | Target IP must be 127.0.0.1                         | 127.0.0.1                  | 0.0.0.0          |
+| `[BODY] == 1`                    | The body must be equal to 1                         | 1                          | `{}`, `2`, ...   |
+| `[BODY].user.name == john`       | JSONPath value of `$.user.name` is equal to `john`  | `{"user":{"name":"john"}}` |                  |
+| `[BODY].data[0].id == 1`         | JSONPath value of `$.data[0].id` is equal to 1      | `{"data":[{"id":1}]}`      |                  |
+| `[BODY].age == [BODY].id`        | JSONPath value of `$.age` is equal JSONPath `$.id`  | `{"age":1,"id":1}`         |                  |
+| `len([BODY].data) < 5`           | Array at JSONPath `$.data` has less than 5 elements | `{"data":[{"id":1}]}`      |                  |
+| `len([BODY].name) == 8`          | String at JSONPath `$.name` has a length of 8       | `{"name":"john.doe"}`      | `{"name":"bob"}` |
+| `has([BODY].errors) == false`    | JSONPath `$.errors` does not exist                  | `{"name":"john.doe"}`      | `{"errors":[]}`  |
+| `has([BODY].users) == true`      | JSONPath `$.users` exists                           | `{"users":[]}`             | `{}`             |
+| `[BODY].name == pat(john*)`      | String at JSONPath `$.name` matches pattern `john*` | `{"name":"john.doe"}`      | `{"name":"bob"}` |
+| `[BODY].id == any(1, 2)`         | Value at JSONPath `$.id` is equal to `1` or `2`     | 1, 2                       | 3, 4, 5          |
+| `[CERTIFICATE_EXPIRATION] > 48h` | Certificate expiration is more than 48h away        | 49h, 50h, 123h             | 1h, 24h, ...     |
 
 
 #### Placeholders
-| Placeholder                | Description                                                     | Example of resolved value |
-|:-------------------------- |:--------------------------------------------------------------- |:------------------------- |
-| `[STATUS]`                 | Resolves into the HTTP status of the request                    | 404
-| `[RESPONSE_TIME]`          | Resolves into the response time the request took, in ms         | 10
-| `[IP]`                     | Resolves into the IP of the target host                         | 192.168.0.232
-| `[BODY]`                   | Resolves into the response body. Supports JSONPath.             | `{"name":"john.doe"}`
-| `[CONNECTED]`              | Resolves into whether a connection could be established         | `true`
-| `[CERTIFICATE_EXPIRATION]` | Resolves into the duration before certificate expiration        | `24h`, `48h`, 0 (if not protocol with certs)
-| `[DNS_RCODE]`              | Resolves into the DNS status of the response                    | NOERROR
+| Placeholder                | Description                                              | Example of resolved value                    |
+|:---------------------------|:---------------------------------------------------------|:---------------------------------------------|
+| `[STATUS]`                 | Resolves into the HTTP status of the request             | 404                                          |
+| `[RESPONSE_TIME]`          | Resolves into the response time the request took, in ms  | 10                                           |
+| `[IP]`                     | Resolves into the IP of the target host                  | 192.168.0.232                                |
+| `[BODY]`                   | Resolves into the response body. Supports JSONPath.      | `{"name":"john.doe"}`                        |
+| `[CONNECTED]`              | Resolves into whether a connection could be established  | `true`                                       |
+| `[CERTIFICATE_EXPIRATION]` | Resolves into the duration before certificate expiration | `24h`, `48h`, 0 (if not protocol with certs) |
+| `[DNS_RCODE]`              | Resolves into the DNS status of the response             | NOERROR                                      |
 
 
 #### Functions
-| Function   | Description                                                                                                      | Example                    |
-|:-----------|:---------------------------------------------------------------------------------------------------------------- |:-------------------------- |
-| `len`      | Returns the length of the object/slice. Works only with the `[BODY]` placeholder.                                | `len([BODY].username) > 8`
-| `has`      | Returns `true` or `false` based on whether a given path is valid. Works only with the `[BODY]` placeholder.      | `has([BODY].errors) == false`
-| `pat`      | Specifies that the string passed as parameter should be evaluated as a pattern. Works only with `==` and `!=`.   | `[IP] == pat(192.168.*)`
-| `any`      | Specifies that any one of the values passed as parameters is a valid value. Works only with `==` and `!=`.       | `[BODY].ip == any(127.0.0.1, ::1)`
+| Function | Description                                                                                                    | Example                            |
+|:---------|:---------------------------------------------------------------------------------------------------------------|:-----------------------------------|
+| `len`    | Returns the length of the object/slice. Works only with the `[BODY]` placeholder.                              | `len([BODY].username) > 8`         |
+| `has`    | Returns `true` or `false` based on whether a given path is valid. Works only with the `[BODY]` placeholder.    | `has([BODY].errors) == false`      |
+| `pat`    | Specifies that the string passed as parameter should be evaluated as a pattern. Works only with `==` and `!=`. | `[IP] == pat(192.168.*)`           |
+| `any`    | Specifies that any one of the values passed as parameters is a valid value. Works only with `==` and `!=`.     | `[BODY].ip == any(127.0.0.1, ::1)` |
 
 **NOTE**: Use `pat` only when you need to. `[STATUS] == pat(2*)` is a lot more expensive than `[STATUS] < 300`.
 
 
 ### Storage
-| Parameter          | Description                                                                            | Default        |
-|:------------------ |:-------------------------------------------------------------------------------------- |:-------------- |
-| `storage`          | Storage configuration                                                                  | `{}`           |
-| `storage.path`     | Path to persist the data in. Only supported for types `sqlite` and `postgres`.         | `""`           |
-| `storage.type`     | Type of storage. Valid types: `memory`, `sqlite`, `postgres`.                          | `"memory"`     |
+| Parameter      | Description                                                                    | Default    |
+|:---------------|:-------------------------------------------------------------------------------|:-----------|
+| `storage`      | Storage configuration                                                          | `{}`       |
+| `storage.path` | Path to persist the data in. Only supported for types `sqlite` and `postgres`. | `""`       |
+| `storage.type` | Type of storage. Valid types: `memory`, `sqlite`, `postgres`.                  | `"memory"` |
 
 - If `storage.type` is `memory` (default):
 ```yaml
@@ -266,11 +273,16 @@ See [examples/docker-compose-postgres-storage](.examples/docker-compose-postgres
 In order to support a wide range of environments, each monitored endpoint has a unique configuration for 
 the client used to send the request.
 
-| Parameter                | Description                                                                   | Default        |
-|:-------------------------|:----------------------------------------------------------------------------- |:-------------- |
-| `client.insecure`        | Whether to skip verifying the server's certificate chain and host name.       | `false`        |
-| `client.ignore-redirect` | Whether to ignore redirects (true) or follow them (false, default).           | `false`        |
-| `client.timeout`         | Duration before timing out.                                                   | `10s`          |
+| Parameter                     | Description                                                                | Default         |
+|:------------------------------|:---------------------------------------------------------------------------|:----------------|
+| `client.insecure`             | Whether to skip verifying the server's certificate chain and host name.    | `false`         |
+| `client.ignore-redirect`      | Whether to ignore redirects (true) or follow them (false, default).        | `false`         |
+| `client.timeout`              | Duration before timing out.                                                | `10s`           |
+| `client.oauth2`               | OAuth2 client configuration.                                               | `{}`            |
+| `client.oauth2.token-url`     | The token endpoint URL                                                     | required `""`   |
+| `client.oauth2.client-id`     | The client id which should be used for the `Client credentials flow`       | required `""`   |
+| `client.oauth2.client-secret` | The client secret which should be used for the `Client credentials flow`   | required `""`   |
+| `client.oauth2.scopes[]`      | A list of `scopes` which should be used for the `Client credentials flow`. | required `[""]` |
 
 Note that some of these parameters are ignored based on the type of endpoint. For instance, there's no certificate involved
 in ICMP requests (ping), therefore, setting `client.insecure` to `true` for an endpoint of that type will not do anything.
@@ -297,6 +309,20 @@ endpoints:
       - "[STATUS] == 200"
 ```
 
+This example shows how you can use the `client.oauth2` configuration to query a backend API with `Bearer token`:
+```yaml
+endpoints:
+  - name: website
+    url: "https://your.health.api/getHealth"
+    client:
+      oauth2:
+        token-url: https://your-token-server/token
+        client-id: 00000000-0000-0000-0000-000000000000
+        client-secret: your-client-secret
+        scopes: ['https://your.health.api/.default']
+    conditions:
+      - "[STATUS] == 200"
+```
 
 ### Alerting
 Gatus supports multiple alerting providers, such as Slack and PagerDuty, and supports different alerts for each
@@ -305,25 +331,28 @@ individual endpoints with configurable descriptions and thresholds.
 Note that if an alerting provider is not properly configured, all alerts configured with the provider's type will be
 ignored.
 
-| Parameter              | Description                                                                                                            | Default        |
-|:-----------------------|:---------------------------------------------------------------------------------------------------------------------- |:-------|
-| `alerting.discord`     | Configuration for alerts of type `discord`. <br />See [Configuring Discord alerts](#configuring-discord-alerts).             | `{}`   |
-| `alerting.mattermost`  | Configuration for alerts of type `mattermost`. <br />See [Configuring Mattermost alerts](#configuring-mattermost-alerts).   | `{}`   |
-| `alerting.messagebird` | Configuration for alerts of type `messagebird`. <br />See [Configuring Messagebird alerts](#configuring-messagebird-alerts). | `{}`   |
-| `alerting.pagerduty`   | Configuration for alerts of type `pagerduty`. <br />See [Configuring PagerDuty alerts](#configuring-pagerduty-alerts).       | `{}`   |
-| `alerting.slack`       | Configuration for alerts of type `slack`. <br />See [Configuring Slack alerts](#configuring-slack-alerts).                   | `{}`   |
-| `alerting.teams`       | Configuration for alerts of type `teams`. <br />See [Configuring Teams alerts](#configuring-teams-alerts).                   | `{}`   |
-| `alerting.telegram`    | Configuration for alerts of type `telegram`. <br />See [Configuring Telegram alerts](#configuring-telegram-alerts).          | `{}`   |
-| `alerting.twilio`      | Settings for alerts of type `twilio`. <br />See [Configuring Twilio alerts](#configuring-twilio-alerts).                     | `{}`   |
-| `alerting.custom`      | Configuration for custom actions on failure or alerts. <br />See [Configuring Custom alerts](#configuring-custom-alerts).    | `{}`   |
+| Parameter              | Description                                                                                                                  | Default |
+|:-----------------------|:-----------------------------------------------------------------------------------------------------------------------------|:--------|
+| `alerting.discord`     | Configuration for alerts of type `discord`. <br />See [Configuring Discord alerts](#configuring-discord-alerts).             | `{}`    |
+| `alerting.email`       | Configuration for alerts of type `email`. <br />See [Configuring Email alerts](#configuring-email-alerts).                   | `{}`    |
+| `alerting.googlechat`  | Configuration for alerts of type `googlechat`. <br />See [Configuring Google Chat alerts](#configuring-google-chat-alerts).  | `{}`    |
+| `alerting.mattermost`  | Configuration for alerts of type `mattermost`. <br />See [Configuring Mattermost alerts](#configuring-mattermost-alerts).    | `{}`    |
+| `alerting.messagebird` | Configuration for alerts of type `messagebird`. <br />See [Configuring Messagebird alerts](#configuring-messagebird-alerts). | `{}`    |
+| `alerting.opsgenie`    | Configuration for alerts of type `opsgenie`. <br />See [Configuring Opsgenie alerts](#configuring-opsgenie-alerts).          | `{}`    |
+| `alerting.pagerduty`   | Configuration for alerts of type `pagerduty`. <br />See [Configuring PagerDuty alerts](#configuring-pagerduty-alerts).       | `{}`    |
+| `alerting.slack`       | Configuration for alerts of type `slack`. <br />See [Configuring Slack alerts](#configuring-slack-alerts).                   | `{}`    |
+| `alerting.teams`       | Configuration for alerts of type `teams`. <br />See [Configuring Teams alerts](#configuring-teams-alerts).                   | `{}`    |
+| `alerting.telegram`    | Configuration for alerts of type `telegram`. <br />See [Configuring Telegram alerts](#configuring-telegram-alerts).          | `{}`    |
+| `alerting.twilio`      | Settings for alerts of type `twilio`. <br />See [Configuring Twilio alerts](#configuring-twilio-alerts).                     | `{}`    |
+| `alerting.custom`      | Configuration for custom actions on failure or alerts. <br />See [Configuring Custom alerts](#configuring-custom-alerts).    | `{}`    |
 
 
 #### Configuring Discord alerts
-| Parameter                                | Description                                  | Default        |
-|:---------------------------------------- |:-------------------------------------------- |:-------------- |
-| `alerting.discord`                       | Configuration for alerts of type `discord`   | `{}`           |
-| `alerting.discord.webhook-url`           | Discord Webhook URL                          | Required `""`  |
-| `alerting.discord.default-alert`         | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A       |
+| Parameter                        | Description                                                                                | Default       |
+|:---------------------------------|:-------------------------------------------------------------------------------------------|:--------------|
+| `alerting.discord`               | Configuration for alerts of type `discord`                                                 | `{}`          |
+| `alerting.discord.webhook-url`   | Discord Webhook URL                                                                        | Required `""` |
+| `alerting.discord.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A           |
 
 ```yaml
 alerting:
@@ -346,13 +375,101 @@ endpoints:
 ```
 
 
+#### Configuring Email alerts
+| Parameter                          | Description                                                                                | Default       |
+|:---------------------------------- |:------------------------------------------------------------------------------------------ |:------------- |
+| `alerting.email`                   | Configuration for alerts of type `email`                                                   | `{}`          |
+| `alerting.email.from`              | Email used to send the alert                                                               | Required `""` |
+| `alerting.email.username`          | Username of the SMTP server used to send the alert. If empty, uses `alerting.email.from`.  | `""`          |
+| `alerting.email.password`          | Password of the SMTP server used to send the alert                                         | Required `""` |
+| `alerting.email.host`              | Host of the mail server (e.g. `smtp.gmail.com`)                                            | Required `""` |
+| `alerting.email.port`              | Port the mail server is listening to (e.g. `587`)                                          | Required `0`  |
+| `alerting.email.to`                | Email(s) to send the alerts to                                                             | Required `""` |
+| `alerting.email.default-alert`     | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A           |
+| `alerting.email.overrides`         | List of overrides that may be prioritized over the default configuration                   | `[]`          |
+| `alerting.email.overrides[].group` | Endpoint group for which the configuration will be overridden by this configuration        | `""`          |
+| `alerting.email.overrides[].to`    | Email(s) to send the alerts to                                                             | `""`          |
+
+```yaml
+alerting:
+  email:
+    from: "from@example.com"
+    username: "from@example.com"
+    password: "hunter2"
+    host: "mail.example.com"
+    port: 587
+    to: "recipient1@example.com,recipient2@example.com"
+    # You can also add group-specific to keys, which will 
+    # override the to key above for the specified groups
+    overrides:
+      - group: "core"
+        to: "recipient3@example.com,recipient4@example.com"
+
+endpoints:
+  - name: website
+    url: "https://twin.sh/health"
+    interval: 5m
+    conditions:
+      - "[STATUS] == 200"
+      - "[BODY].status == UP"
+      - "[RESPONSE_TIME] < 300"
+    alerts:
+      - type: email
+        enabled: true
+        description: "healthcheck failed"
+        send-on-resolved: true
+
+  - name: back-end
+    group: core
+    url: "https://example.org/"
+    interval: 5m
+    conditions:
+      - "[STATUS] == 200"
+      - "[CERTIFICATE_EXPIRATION] > 48h"
+    alerts:
+      - type: email
+        enabled: true
+        description: "healthcheck failed"
+        send-on-resolved: true
+```
+
+**NOTE:** Some mail servers are painfully slow.
+
+#### Configuring Google Chat alerts
+| Parameter                           | Description                                                                                 | Default       |
+|:------------------------------------|:--------------------------------------------------------------------------------------------|:--------------|
+| `alerting.googlechat`               | Configuration for alerts of type `googlechat`                                               | `{}`          |
+| `alerting.googlechat.webhook-url`   | Google Chat Webhook URL                                                                     | Required `""` |
+| `alerting.googlechat.client`        | Client configuration. <br />See [Client configuration](#client-configuration).              | `{}`          |
+| `alerting.googlechat.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert). | N/A           |
+
+```yaml
+alerting:
+  googlechat: 
+    webhook-url: "https://chat.googleapis.com/v1/spaces/*******/messages?key=**********&token=********"
+
+endpoints:
+  - name: website
+    url: "https://twin.sh/health"
+    interval: 30s
+    conditions:
+      - "[STATUS] == 200"
+      - "[BODY].status == UP"
+      - "[RESPONSE_TIME] < 300"
+    alerts:
+      - type: googlechat
+        enabled: true
+        description: "healthcheck failed"
+        send-on-resolved: true
+```
+
 #### Configuring Mattermost alerts
-| Parameter                           | Description                                                                                 | Default        |
-|:----------------------------------- |:------------------------------------------------------------------------------------------- |:-------------- |
-| `alerting.mattermost`               | Configuration for alerts of type `mattermost`                                               | `{}`           |
-| `alerting.mattermost.webhook-url`   | Mattermost Webhook URL                                                                      | Required `""`  |
-| `alerting.mattermost.client`        | Client configuration. <br />See [Client configuration](#client-configuration).              | `{}`           |
-| `alerting.mattermost.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert). | N/A            |
+| Parameter                           | Description                                                                                 | Default       |
+|:------------------------------------|:--------------------------------------------------------------------------------------------|:--------------|
+| `alerting.mattermost`               | Configuration for alerts of type `mattermost`                                               | `{}`          |
+| `alerting.mattermost.webhook-url`   | Mattermost Webhook URL                                                                      | Required `""` |
+| `alerting.mattermost.client`        | Client configuration. <br />See [Client configuration](#client-configuration).              | `{}`          |
+| `alerting.mattermost.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert). | N/A           |
 
 ```yaml
 alerting:
@@ -380,15 +497,14 @@ Here's an example of what the notifications look like:
 
 ![Mattermost notifications](.github/assets/mattermost-alerts.png)
 
-
 #### Configuring Messagebird alerts
-| Parameter                            | Description                                                                   | Default        |
-|:-------------------------------------|:----------------------------------------------------------------------------- |:-------------- |
-| `alerting.messagebird`               | Settings for alerts of type `messagebird`                                     | `{}`           |
-| `alerting.messagebird.access-key`    | Messagebird access key                                                        | Required `""`  |
-| `alerting.messagebird.originator`    | The sender of the message                                                     | Required `""`  |
-| `alerting.messagebird.recipients`    | The recipients of the message                                                 | Required `""`  |
-| `alerting.messagebird.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A       |
+| Parameter                            | Description                                                                                | Default       |
+|:-------------------------------------|:-------------------------------------------------------------------------------------------|:--------------|
+| `alerting.messagebird`               | Settings for alerts of type `messagebird`                                                  | `{}`          |
+| `alerting.messagebird.access-key`    | Messagebird access key                                                                     | Required `""` |
+| `alerting.messagebird.originator`    | The sender of the message                                                                  | Required `""` |
+| `alerting.messagebird.recipients`    | The recipients of the message                                                              | Required `""` |
+| `alerting.messagebird.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A           |
 
 Example of sending **SMS** text message alert using Messagebird:
 ```yaml
@@ -415,26 +531,46 @@ endpoints:
 ```
 
 
+#### Configuring Opsgenie alerts
+| Parameter                         | Description                                                                                | Default              |
+|:----------------------------------|:-------------------------------------------------------------------------------------------|:---------------------|
+| `alerting.opsgenie`               | Configuration for alerts of type `opsgenie`                                                | `{}`                 |
+| `alerting.opsgenie.api-key`       | Opsgenie API Key                                                                           | Required `""`        |
+| `alerting.opsgenie.priority`      | Priority level of the alert.                                                               | `P1`                 |
+| `alerting.opsgenie.source`        | Source field of the alert.                                                                 | `gatus`              |
+| `alerting.opsgenie.entity-prefix` | Entity field prefix.                                                                       | `gatus-`             |
+| `alerting.opsgenie.alias-prefix`  | Alias field prefix.                                                                        | `gatus-healthcheck-` |
+| `alerting.opsgenie.tags`          | Tags of alert.                                                                             | `[]`                 |
+| `alerting.opsgenie.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A                  |
+
+Opsgenie provider will automatically open and close alerts.
+
+```yaml
+alerting:
+  opsgenie:
+    api-key: "00000000-0000-0000-0000-000000000000"
+```
+
+
 #### Configuring PagerDuty alerts
-| Parameter                                              | Description                                                                   | Default        |
-|:------------------------------------------------------ |:----------------------------------------------------------------------------- |:-------------- |
-| `alerting.pagerduty`                                   | Configuration for alerts of type `pagerduty`                                  | `{}`           |
-| `alerting.pagerduty.integration-key`                   | PagerDuty Events API v2 integration key                                       | `""`           |
-| `alerting.pagerduty.default-alert`                     | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A       |
-| `alerting.pagerduty.overrides`                         | List of overrides that may be prioritized over the default configuration      |   `[]`         |
-| `alerting.pagerduty.overrides[].group`                 | Endpoint group for which the configuration will be overridden by this configuration |   `""`         |
-| `alerting.pagerduty.overrides[].integration-key`       | PagerDuty Events API v2 integration key                                       |   `""`         |
+| Parameter                                        | Description                                                                                | Default |
+|:-------------------------------------------------|:-------------------------------------------------------------------------------------------|:--------|
+| `alerting.pagerduty`                             | Configuration for alerts of type `pagerduty`                                               | `{}`    |
+| `alerting.pagerduty.integration-key`             | PagerDuty Events API v2 integration key                                                    | `""`    |
+| `alerting.pagerduty.overrides`                   | List of overrides that may be prioritized over the default configuration                   | `[]`    |
+| `alerting.pagerduty.overrides[].group`           | Endpoint group for which the configuration will be overridden by this configuration        | `""`    |
+| `alerting.pagerduty.overrides[].integration-key` | PagerDuty Events API v2 integration key                                                    | `""`    |
+| `alerting.pagerduty.default-alert`               | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A     |
 
 It is highly recommended to set `endpoints[].alerts[].send-on-resolved` to `true` for alerts
 of type `pagerduty`, because unlike other alerts, the operation resulting from setting said
-parameter to `true` will not create another incident, but mark the incident as resolved on
+parameter to `true` will not create another incident but mark the incident as resolved on
 PagerDuty instead.
 
 Behavior:
 - By default, `alerting.pagerduty.integration-key` is used as the integration key
 - If the endpoint being evaluated belongs to a group (`endpoints[].group`) matching the value of `alerting.pagerduty.overrides[].group`, the provider will use that override's integration key instead of `alerting.pagerduty.integration-key`'s
 
-
 ```yaml
 alerting:
   pagerduty: 
@@ -442,8 +578,8 @@ alerting:
     # You can also add group-specific integration keys, which will 
     # override the integration key above for the specified groups
     overrides:
-     - group: "core"
-       integration-key: "********************************"
+      - group: "core"
+        integration-key: "********************************"
 
 endpoints:
   - name: website
@@ -479,11 +615,11 @@ endpoints:
 
 
 #### Configuring Slack alerts
-| Parameter                        | Description                                                                   | Default        |
-|:-------------------------------- |:----------------------------------------------------------------------------- |:-------------- |
-| `alerting.slack`                 | Configuration for alerts of type `slack`                                      | `{}`           |
-| `alerting.slack.webhook-url`     | Slack Webhook URL                                                             | Required `""`  |
-| `alerting.slack.default-alert`   | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A       |
+| Parameter                      | Description                                                                                | Default       |
+|:-------------------------------|:-------------------------------------------------------------------------------------------|:--------------|
+| `alerting.slack`               | Configuration for alerts of type `slack`                                                   | `{}`          |
+| `alerting.slack.webhook-url`   | Slack Webhook URL                                                                          | Required `""` |
+| `alerting.slack.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A           |
 
 ```yaml
 alerting:
@@ -516,11 +652,11 @@ Here's an example of what the notifications look like:
 
 
 #### Configuring Teams alerts
-| Parameter                        | Description                                                                   | Default        |
-|:-------------------------------- |:----------------------------------------------------------------------------- |:-------------- |
-| `alerting.teams`                 | Configuration for alerts of type `teams`                                      | `{}`           |
-| `alerting.teams.webhook-url`     | Teams Webhook URL                                                             | Required `""`  |
-| `alerting.teams.default-alert`   | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A       |
+| Parameter                      | Description                                                                                | Default       |
+|:-------------------------------|:-------------------------------------------------------------------------------------------|:--------------|
+| `alerting.teams`               | Configuration for alerts of type `teams`                                                   | `{}`          |
+| `alerting.teams.webhook-url`   | Teams Webhook URL                                                                          | Required `""` |
+| `alerting.teams.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A           |
 
 ```yaml
 alerting:
@@ -547,12 +683,13 @@ Here's an example of what the notifications look like:
 ![Teams notifications](.github/assets/teams-alerts.png)
 
 #### Configuring Telegram alerts
-| Parameter                           | Description                                                                   | Default        |
-|:----------------------------------- |:----------------------------------------------------------------------------- |:-------------- |
-| `alerting.telegram`                 | Configuration for alerts of type `telegram`                                   | `{}`           |
-| `alerting.telegram.token`           | Telegram Bot Token                                                            | Required `""`  |
-| `alerting.telegram.id`              | Telegram User ID                                                              | Required `""`  |
-| `alerting.telegram.default-alert`   | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A       |
+| Parameter                         | Description                                                                                | Default                    |
+|:----------------------------------|:-------------------------------------------------------------------------------------------|:---------------------------|
+| `alerting.telegram`               | Configuration for alerts of type `telegram`                                                | `{}`                       |
+| `alerting.telegram.token`         | Telegram Bot Token                                                                         | Required `""`              |
+| `alerting.telegram.id`            | Telegram User ID                                                                           | Required `""`              |
+| `alerting.telegram.api-url`       | Telegram API URL                                                                           | `https://api.telegram.org` |
+| `alerting.telegram.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A                        |
 
 ```yaml
 alerting:
@@ -579,14 +716,14 @@ Here's an example of what the notifications look like:
 
 
 #### Configuring Twilio alerts
-| Parameter                         | Description                                                                   | Default        |
-|:--------------------------------- |:----------------------------------------------------------------------------- |:-------------- |
-| `alerting.twilio`                 | Settings for alerts of type `twilio`                                          | `{}`           |
-| `alerting.twilio.sid`             | Twilio account SID                                                            | Required `""`  |
-| `alerting.twilio.token`           | Twilio auth token                                                             | Required `""`  |
-| `alerting.twilio.from`            | Number to send Twilio alerts from                                             | Required `""`  |
-| `alerting.twilio.to`              | Number to send twilio alerts to                                               | Required `""`  |
-| `alerting.twilio.default-alert`   | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A       |
+| Parameter                       | Description                                                                                | Default       |
+|:--------------------------------|:-------------------------------------------------------------------------------------------|:--------------|
+| `alerting.twilio`               | Settings for alerts of type `twilio`                                                       | `{}`          |
+| `alerting.twilio.sid`           | Twilio account SID                                                                         | Required `""` |
+| `alerting.twilio.token`         | Twilio auth token                                                                          | Required `""` |
+| `alerting.twilio.from`          | Number to send Twilio alerts from                                                          | Required `""` |
+| `alerting.twilio.to`            | Number to send twilio alerts to                                                            | Required `""` |
+| `alerting.twilio.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A           |
 
 ```yaml
 alerting:
@@ -614,15 +751,15 @@ endpoints:
 
 
 #### Configuring custom alerts
-| Parameter                         | Description                                                                   | Default        |
-|:----------------------------------|:----------------------------------------------------------------------------- |:-------------- |
-| `alerting.custom`                 | Configuration for custom actions on failure or alerts                         | `{}`           |
-| `alerting.custom.url`             | Custom alerting request url                                                   | Required `""`  |
-| `alerting.custom.method`          | Request method                                                                | `GET`          |
-| `alerting.custom.body`            | Custom alerting request body.                                                 | `""`           |
-| `alerting.custom.headers`         | Custom alerting request headers                                               | `{}`           |
-| `alerting.custom.client`          | Client configuration. <br />See [Client configuration](#client-configuration).      | `{}`           |
-| `alerting.custom.default-alert`   | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A       |
+| Parameter                       | Description                                                                                | Default       |
+|:--------------------------------|:-------------------------------------------------------------------------------------------|:--------------|
+| `alerting.custom`               | Configuration for custom actions on failure or alerts                                      | `{}`          |
+| `alerting.custom.url`           | Custom alerting request url                                                                | Required `""` |
+| `alerting.custom.method`        | Request method                                                                             | `GET`         |
+| `alerting.custom.body`          | Custom alerting request body.                                                              | `""`          |
+| `alerting.custom.headers`       | Custom alerting request headers                                                            | `{}`          |
+| `alerting.custom.client`        | Client configuration. <br />See [Client configuration](#client-configuration).             | `{}`          |
+| `alerting.custom.default-alert` | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A           |
 
 While they're called alerts, you can use this feature to call anything. 
 
@@ -639,7 +776,7 @@ If you have an alert using the `custom` provider with `send-on-resolved` set to
 The aforementioned placeholder will be replaced by `TRIGGERED` or `RESOLVED` accordingly, though it can be modified
 (details at the end of this section).
 
-For all intents and purpose, we'll configure the custom alert with a Slack webhook, but you can call anything you want.
+For all intents and purposes, we'll configure the custom alert with a Slack webhook, but you can call anything you want.
 ```yaml
 alerting:
   custom:
@@ -774,12 +911,12 @@ endpoints:
 If you have maintenance windows, you may not want to be annoyed by alerts. 
 To do that, you'll have to use the maintenance configuration:
 
-| Parameter               | Description                                                                   | Default         |
-|:----------------------- |:----------------------------------------------------------------------------- |:--------------- |
-| `maintenance.enabled`   | Whether the maintenance period is enabled                                     | `true`          |
-| `maintenance.start`     | Time at which the maintenance window starts in `hh:mm` format (e.g. `23:00`)  | Required `""`   |
-| `maintenance.duration`  | Duration of the maintenance window (e.g. `1h`, `30m`)                         | Required `""`   |
-| `maintenance.every`     | Days on which the maintenance period applies (e.g. `[Monday, Thursday]`).<br />If left empty, the maintenance window applies every day | `[]` |
+| Parameter              | Description                                                                                                                            | Default       |
+|:-----------------------|:---------------------------------------------------------------------------------------------------------------------------------------|:--------------|
+| `maintenance.enabled`  | Whether the maintenance period is enabled                                                                                              | `true`        |
+| `maintenance.start`    | Time at which the maintenance window starts in `hh:mm` format (e.g. `23:00`)                                                           | Required `""` |
+| `maintenance.duration` | Duration of the maintenance window (e.g. `1h`, `30m`)                                                                                  | Required `""` |
+| `maintenance.every`    | Days on which the maintenance period applies (e.g. `[Monday, Thursday]`).<br />If left empty, the maintenance window applies every day | `[]`          |
 
 **Note that the maintenance configuration uses UTC.**
 
@@ -801,6 +938,56 @@ maintenance:
 ```
 
 
+### Security
+| Parameter                        | Description                  | Default       |
+|:---------------------------------|:-----------------------------|:--------------|
+| `security`                       | Security configuration       | `{}`          |
+| `security.basic`                 | HTTP Basic configuration     | `{}`          |
+| `security.oidc`                  | OpenID Connect configuration | `{}`          |
+
+#### Basic
+| Parameter                               | Description                                                                        | Default       |
+|:----------------------------------------|:-----------------------------------------------------------------------------------|:--------------|
+| `security.basic`                        | HTTP Basic configuration                                                           | `{}`          |
+| `security.basic.username`               | Username for Basic authentication.                                                 | Required `""` |
+| `security.basic.password-bcrypt-base64` | Password hashed with Bcrypt and then encoded with base64 for Basic authentication. | Required `""` |
+
+The example below will require that you authenticate with the username `john.doe` and the password `hunter2`:
+```yaml
+security:
+  basic:
+    username: "john.doe"
+    password-bcrypt-base64: "JDJhJDEwJHRiMnRFakxWazZLdXBzRERQazB1TE8vckRLY05Yb1hSdnoxWU0yQ1FaYXZRSW1McmladDYu"
+```
+
+**WARNING:** Make sure to carefully select to cost of the bcrypt hash. The higher the cost, the longer it takes to compute the hash,
+and basic auth verifies the password against the hash on every request. As of 2022-01-08, I suggest a cost of 8.
+
+#### OIDC (ALPHA)
+| Parameter                        | Description                                                    | Default       |
+|:---------------------------------|:---------------------------------------------------------------|:--------------|
+| `security.oidc`                  | OpenID Connect configuration                                   | `{}`          |
+| `security.oidc.issuer-url`       | Issuer URL                                                     | Required `""` |
+| `security.oidc.redirect-url`     | Redirect URL. Must end with `/authorization-code/callback`     | Required `""` |
+| `security.oidc.client-id`        | Client id                                                      | Required `""` |
+| `security.oidc.client-secret`    | Client secret                                                  | Required `""` |
+| `security.oidc.scopes`           | Scopes to request. The only scope you need is `openid`.        | Required `[]` |
+| `security.oidc.allowed-subjects` | List of subjects to allow. If empty, all subjects are allowed. | `[]`          |
+
+```yaml
+security:
+  oidc:
+    issuer-url: "https://example.okta.com"
+    redirect-url: "https://status.example.com/authorization-code/callback"
+    client-id: "123456789"
+    client-secret: "abcdefghijk"
+    scopes: ["openid"]
+    # You may optionally specify a list of allowed subjects. If this is not specified, all subjects will be allowed.
+    #allowed-subjects: ["johndoe@example.com"]
+```
+
+**NOTE:** The OIDC feature is currently in Alpha. Breaking changes may occur. Use this feature at your own risk.
+
 
 ## Deployment
 Many examples can be found in the [.examples](.examples) folder, but this section will focus on the most popular ways of deploying Gatus.
@@ -895,7 +1082,7 @@ will send a `POST` request to `http://localhost:8080/playground` with the follow
 > tells Gatus to only evaluate one endpoint at a time.
 
 To ensure that Gatus provides reliable and accurate results (i.e. response time), Gatus only evaluates one endpoint at a time
-In other words, even if you have multiple endpoints with the exact same interval, they will not execute at the same time.
+In other words, even if you have multiple endpoints with the same interval, they will not execute at the same time.
 
 You can test this yourself by running Gatus with several endpoints configured with a very short, unrealistic interval, 
 such as 1ms. You'll notice that the response time does not fluctuate - that is because while endpoints are evaluated on
@@ -913,10 +1100,10 @@ to respect the configured interval, for instance:
 - Endpoint B has an interval of 5s, and takes 1ms to complete
 - Endpoint B will be unable to run every 5s, because endpoint A's health evaluation takes longer than its interval
 
-To sum it up, while Gatus can really handle any interval you throw at it, you're better off having slow requests with 
+To sum it up, while Gatus can handle any interval you throw at it, you're better off having slow requests with 
 higher interval.
 
-As a rule of the thumb, I personally set interval for more complex health checks to `5m` (5 minutes) and 
+As a rule of thumb, I personally set the interval for more complex health checks to `5m` (5 minutes) and 
 simple health checks used for alerting (PagerDuty/Twilio) to `30s`.
 
 
@@ -1018,18 +1205,6 @@ endpoints:
 ```
 
 
-### Basic authentication
-You can require Basic authentication by leveraging the `security.basic` configuration:
-```yaml
-security:
-  basic:
-    username: "john.doe"
-    password-sha512: "6b97ed68d14eb3f1aa959ce5d49c7dc612e1eb1dafd73b1e705847483fd6a6c809f2ceb4e8df6ff9984c6298ff0285cace6614bf8daa9f0070101b6c89899e22"
-```
-
-The example above will require that you authenticate with the username `john.doe` as well as the password `hunter2`.
-
-
 ### disable-monitoring-lock
 Setting `disable-monitoring-lock` to `true` means that multiple endpoints could be monitored at the same time.
 
@@ -1040,11 +1215,11 @@ There are three main reasons why you might want to disable the monitoring lock:
 - You're using Gatus for load testing (each endpoint are periodically evaluated on a different goroutine, so 
 technically, if you create 100 endpoints with a 1 seconds interval, Gatus will send 100 requests per second)
 - You have a _lot_ of endpoints to monitor
-- You want to test multiple endpoints at very short interval (< 5s)
+- You want to test multiple endpoints at very short intervals (< 5s)
 
 
 ### Reloading configuration on the fly
-For the sake on convenience, Gatus automatically reloads the configuration on the fly if the loaded configuration file
+For the sake of convenience, Gatus automatically reloads the configuration on the fly if the loaded configuration file
 is updated while Gatus is running.
 
 By default, the application will exit if the updating configuration is invalid, but you can configure
@@ -1129,12 +1304,12 @@ web:
 
 ### Badges
 ### Uptime
-![Uptime 1h](https://status.twin.sh/api/v1/endpoints/core_website-external/uptimes/1h/badge.svg)
-![Uptime 24h](https://status.twin.sh/api/v1/endpoints/core_website-external/uptimes/24h/badge.svg)
-![Uptime 7d](https://status.twin.sh/api/v1/endpoints/core_website-external/uptimes/7d/badge.svg)
+![Uptime 1h](https://status.twin.sh/api/v1/endpoints/core_blog-external/uptimes/1h/badge.svg)
+![Uptime 24h](https://status.twin.sh/api/v1/endpoints/core_blog-external/uptimes/24h/badge.svg)
+![Uptime 7d](https://status.twin.sh/api/v1/endpoints/core_blog-external/uptimes/7d/badge.svg)
 
-Gatus can automatically generate a SVG badge for one of your monitored endpoints.
-This allows you to put badges in your individual applications' README or even create your own status page, if you 
+Gatus can automatically generate an SVG badge for one of your monitored endpoints.
+This allows you to put badges in your individual applications' README or even create your own status page if you 
 desire.
 
 The path to generate a badge is the following:
@@ -1156,15 +1331,15 @@ https://example.com/api/v1/endpoints/_frontend/uptimes/7d/badge.svg
 ```
 Example:
 ```
-![Uptime 24h](https://status.twin.sh/api/v1/endpoints/core_website-external/uptimes/24h/badge.svg)
+![Uptime 24h](https://status.twin.sh/api/v1/endpoints/core_blog-external/uptimes/24h/badge.svg)
 ```
-If you'd like to see a visual example of each badges available, you can simply navigate to the endpoint's detail page.
+If you'd like to see a visual example of each badge available, you can simply navigate to the endpoint's detail page.
 
 
 ### Response time
-![Response time 1h](https://status.twin.sh/api/v1/endpoints/core_website-external/response-times/1h/badge.svg)
-![Response time 24h](https://status.twin.sh/api/v1/endpoints/core_website-external/response-times/24h/badge.svg)
-![Response time 7d](https://status.twin.sh/api/v1/endpoints/core_website-external/response-times/7d/badge.svg)
+![Response time 1h](https://status.twin.sh/api/v1/endpoints/core_blog-external/response-times/1h/badge.svg)
+![Response time 24h](https://status.twin.sh/api/v1/endpoints/core_blog-external/response-times/24h/badge.svg)
+![Response time 7d](https://status.twin.sh/api/v1/endpoints/core_blog-external/response-times/7d/badge.svg)
 
 The endpoint to generate a badge is the following:
 ```
@@ -1176,7 +1351,7 @@ Where:
 
 
 ### API
-Gatus provides a simple read-only API which can be queried in order to programmatically determine endpoint status and history.
+Gatus provides a simple read-only API that can be queried in order to programmatically determine endpoint status and history.
 
 All endpoints are available via a GET request to the following endpoint:
 ```
@@ -1188,7 +1363,7 @@ Specific endpoints can also be queried by using the following pattern:
 ```
 /api/v1/endpoints/{group}_{endpoint}/statuses
 ```
-Example: https://status.twin.sh/api/v1/endpoints/core_website-home/statuses
+Example: https://status.twin.sh/api/v1/endpoints/core_blog-home/statuses
 
 Gzip compression will be used if the `Accept-Encoding` HTTP header contains `gzip`.
 

alerting/alert/alert.go

@@ -1,5 +1,15 @@
 package alert
 
+import (
+	"errors"
+	"strings"
+)
+
+var (
+	// ErrAlertWithInvalidDescription is the error with which Gatus will panic if an alert has an invalid character
+	ErrAlertWithInvalidDescription = errors.New("alert description must not have \" or \\")
+)
+
 // Alert is a core.Endpoint's alert configuration
 type Alert struct {
 	// Type of alert (required)
@@ -9,7 +19,7 @@ type Alert struct {
 	//
 	// This is a pointer, because it is populated by YAML and we need to know whether it was explicitly set to a value
 	// or not for provider.ParseWithDefaultAlert to work.
-	Enabled *bool `yaml:"enabled"`
+	Enabled *bool `yaml:"enabled,omitempty"`
 
 	// FailureThreshold is the number of failures in a row needed before triggering the alert
 	FailureThreshold int `yaml:"failure-threshold"`
@@ -31,7 +41,7 @@ type Alert struct {
 
 	// ResolveKey is an optional field that is used by some providers (i.e. PagerDuty's dedup_key) to resolve
 	// ongoing/triggered incidents
-	ResolveKey string
+	ResolveKey string `yaml:"-"`
 
 	// Triggered is used to determine whether an alert has been triggered. When an alert is resolved, this value
 	// should be set back to false. It is used to prevent the same alert from going out twice.
@@ -41,7 +51,21 @@ type Alert struct {
 	// applied for alerts that are already triggered and has become "healthy" again is to prevent a case where, for
 	// some reason, the alert provider always returns errors when trying to send the resolved notification
 	// (SendOnResolved).
-	Triggered bool
+	Triggered bool `yaml:"-"`
+}
+
+// ValidateAndSetDefaults validates the alert's configuration and sets the default value of fields that have one
+func (alert *Alert) ValidateAndSetDefaults() error {
+	if alert.FailureThreshold <= 0 {
+		alert.FailureThreshold = 3
+	}
+	if alert.SuccessThreshold <= 0 {
+		alert.SuccessThreshold = 2
+	}
+	if strings.ContainsAny(alert.GetDescription(), "\"\\") {
+		return ErrAlertWithInvalidDescription
+	}
+	return nil
 }
 
 // GetDescription retrieves the description of the alert

alerting/alert/alert_test.go

@@ -1,6 +1,55 @@
 package alert
 
-import "testing"
+import (
+	"testing"
+)
+
+func TestAlert_ValidateAndSetDefaults(t *testing.T) {
+	invalidDescription := "\""
+	scenarios := []struct {
+		name                     string
+		alert                    Alert
+		expectedError            error
+		expectedSuccessThreshold int
+		expectedFailureThreshold int
+	}{
+		{
+			name: "valid-empty",
+			alert: Alert{
+				Description:      nil,
+				FailureThreshold: 0,
+				SuccessThreshold: 0,
+			},
+			expectedError:            nil,
+			expectedFailureThreshold: 3,
+			expectedSuccessThreshold: 2,
+		},
+		{
+			name: "invalid-description",
+			alert: Alert{
+				Description:      &invalidDescription,
+				FailureThreshold: 10,
+				SuccessThreshold: 5,
+			},
+			expectedError:            ErrAlertWithInvalidDescription,
+			expectedFailureThreshold: 10,
+			expectedSuccessThreshold: 5,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.name, func(t *testing.T) {
+			if err := scenario.alert.ValidateAndSetDefaults(); err != scenario.expectedError {
+				t.Errorf("expected error %v, got %v", scenario.expectedError, err)
+			}
+			if scenario.alert.SuccessThreshold != scenario.expectedSuccessThreshold {
+				t.Errorf("expected success threshold %v, got %v", scenario.expectedSuccessThreshold, scenario.alert.SuccessThreshold)
+			}
+			if scenario.alert.FailureThreshold != scenario.expectedFailureThreshold {
+				t.Errorf("expected failure threshold %v, got %v", scenario.expectedFailureThreshold, scenario.alert.FailureThreshold)
+			}
+		})
+	}
+}
 
 func TestAlert_IsEnabled(t *testing.T) {
 	if (Alert{Enabled: nil}).IsEnabled() {

alerting/alert/type.go

@@ -11,6 +11,12 @@ const (
 	// TypeDiscord is the Type for the discord alerting provider
 	TypeDiscord Type = "discord"
 
+	// TypeEmail is the Type for the email alerting provider
+	TypeEmail Type = "email"
+
+	// TypeGoogleChat is the Type for the googlechat alerting provider
+	TypeGoogleChat Type = "googlechat"
+
 	// TypeMattermost is the Type for the mattermost alerting provider
 	TypeMattermost Type = "mattermost"
 
@@ -31,4 +37,7 @@ const (
 
 	// TypeTwilio is the Type for the twilio alerting provider
 	TypeTwilio Type = "twilio"
+
+	// TypeOpsgenie is the Type for the opsgenie alerting provider
+	TypeOpsgenie Type = "opsgenie"
 )

alerting/config.go

@@ -5,8 +5,11 @@ import (
 	"github.com/TwiN/gatus/v3/alerting/provider"
 	"github.com/TwiN/gatus/v3/alerting/provider/custom"
 	"github.com/TwiN/gatus/v3/alerting/provider/discord"
+	"github.com/TwiN/gatus/v3/alerting/provider/email"
+	"github.com/TwiN/gatus/v3/alerting/provider/googlechat"
 	"github.com/TwiN/gatus/v3/alerting/provider/mattermost"
 	"github.com/TwiN/gatus/v3/alerting/provider/messagebird"
+	"github.com/TwiN/gatus/v3/alerting/provider/opsgenie"
 	"github.com/TwiN/gatus/v3/alerting/provider/pagerduty"
 	"github.com/TwiN/gatus/v3/alerting/provider/slack"
 	"github.com/TwiN/gatus/v3/alerting/provider/teams"
@@ -17,31 +20,40 @@ import (
 // Config is the configuration for alerting providers
 type Config struct {
 	// Custom is the configuration for the custom alerting provider
-	Custom *custom.AlertProvider `yaml:"custom"`
+	Custom *custom.AlertProvider `yaml:"custom,omitempty"`
+
+	// googlechat is the configuration for the Google chat alerting provider
+	GoogleChat *googlechat.AlertProvider `yaml:"googlechat,omitempty"`
 
 	// Discord is the configuration for the discord alerting provider
-	Discord *discord.AlertProvider `yaml:"discord"`
+	Discord *discord.AlertProvider `yaml:"discord,omitempty"`
+
+	// Email is the configuration for the email alerting provider
+	Email *email.AlertProvider `yaml:"email,omitempty"`
 
 	// Mattermost is the configuration for the mattermost alerting provider
-	Mattermost *mattermost.AlertProvider `yaml:"mattermost"`
+	Mattermost *mattermost.AlertProvider `yaml:"mattermost,omitempty"`
 
 	// Messagebird is the configuration for the messagebird alerting provider
-	Messagebird *messagebird.AlertProvider `yaml:"messagebird"`
+	Messagebird *messagebird.AlertProvider `yaml:"messagebird,omitempty"`
 
 	// PagerDuty is the configuration for the pagerduty alerting provider
-	PagerDuty *pagerduty.AlertProvider `yaml:"pagerduty"`
+	PagerDuty *pagerduty.AlertProvider `yaml:"pagerduty,omitempty"`
 
 	// Slack is the configuration for the slack alerting provider
-	Slack *slack.AlertProvider `yaml:"slack"`
+	Slack *slack.AlertProvider `yaml:"slack,omitempty"`
 
 	// Teams is the configuration for the teams alerting provider
-	Teams *teams.AlertProvider `yaml:"teams"`
+	Teams *teams.AlertProvider `yaml:"teams,omitempty"`
 
 	// Telegram is the configuration for the telegram alerting provider
-	Telegram *telegram.AlertProvider `yaml:"telegram"`
+	Telegram *telegram.AlertProvider `yaml:"telegram,omitempty"`
 
 	// Twilio is the configuration for the twilio alerting provider
-	Twilio *twilio.AlertProvider `yaml:"twilio"`
+	Twilio *twilio.AlertProvider `yaml:"twilio,omitempty"`
+
+	// Opsgenie is the configuration for the opsgenie alerting provider
+	Opsgenie *opsgenie.AlertProvider `yaml:"opsgenie,omitempty"`
 }
 
 // GetAlertingProviderByAlertType returns an provider.AlertProvider by its corresponding alert.Type
@@ -53,12 +65,24 @@ func (config Config) GetAlertingProviderByAlertType(alertType alert.Type) provid
 			return nil
 		}
 		return config.Custom
+	case alert.TypeGoogleChat:
+		if config.GoogleChat == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.GoogleChat
 	case alert.TypeDiscord:
 		if config.Discord == nil {
 			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
 			return nil
 		}
 		return config.Discord
+	case alert.TypeEmail:
+		if config.Email == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Email
 	case alert.TypeMattermost:
 		if config.Mattermost == nil {
 			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
@@ -71,6 +95,12 @@ func (config Config) GetAlertingProviderByAlertType(alertType alert.Type) provid
 			return nil
 		}
 		return config.Messagebird
+	case alert.TypeOpsgenie:
+		if config.Opsgenie == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Opsgenie
 	case alert.TypePagerDuty:
 		if config.PagerDuty == nil {
 			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil

alerting/provider/custom/custom.go

@@ -2,11 +2,9 @@ package custom
 
 import (
 	"bytes"
-	"errors"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
-	"os"
 	"strings"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
@@ -24,10 +22,10 @@ type AlertProvider struct {
 	Placeholders map[string]map[string]string `yaml:"placeholders,omitempty"`
 
 	// ClientConfig is the configuration of the client used to communicate with the provider's target
-	ClientConfig *client.Config `yaml:"client"`
+	ClientConfig *client.Config `yaml:"client,omitempty"`
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
-	DefaultAlert *alert.Alert `yaml:"default-alert"`
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -38,11 +36,6 @@ func (provider *AlertProvider) IsValid() bool {
 	return len(provider.URL) > 0 && provider.ClientConfig != nil
 }
 
-// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) *AlertProvider {
-	return provider
-}
-
 // GetAlertStatePlaceholderValue returns the Placeholder value for ALERT_TRIGGERED_OR_RESOLVED if configured
 func (provider *AlertProvider) GetAlertStatePlaceholderValue(resolved bool) string {
 	status := "TRIGGERED"
@@ -105,27 +98,17 @@ func (provider *AlertProvider) buildHTTPRequest(endpointName, alertDescription s
 	return request
 }
 
-// Send a request to the alert provider and return the body
-func (provider *AlertProvider) Send(endpointName, alertDescription string, resolved bool) ([]byte, error) {
-	if os.Getenv("MOCK_ALERT_PROVIDER") == "true" {
-		if os.Getenv("MOCK_ALERT_PROVIDER_ERROR") == "true" {
-			return nil, errors.New("error")
-		}
-		return []byte("{}"), nil
-	}
-	request := provider.buildHTTPRequest(endpointName, alertDescription, resolved)
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	request := provider.buildHTTPRequest(endpoint.Name, alert.GetDescription(), resolved)
 	response, err := client.GetHTTPClient(provider.ClientConfig).Do(request)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	if response.StatusCode > 399 {
-		body, err := ioutil.ReadAll(response.Body)
-		if err != nil {
-			return nil, fmt.Errorf("call to provider alert returned status code %d", response.StatusCode)
-		}
-		return nil, fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
 	}
-	return ioutil.ReadAll(response.Body)
+	return err
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/custom/custom_test.go

@@ -1,11 +1,14 @@
 package custom
 
 import (
-	"io/ioutil"
+	"io"
+	"net/http"
 	"testing"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -19,6 +22,83 @@ func TestAlertProvider_IsValid(t *testing.T) {
 	}
 }
 
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:     "triggered",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "triggered-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+		{
+			Name:     "resolved",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "resolved-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
+	}
+}
+
 func TestAlertProvider_buildHTTPRequestWhenResolved(t *testing.T) {
 	const (
 		ExpectedURL  = "https://example.com/endpoint-name?event=RESOLVED&description=alert-description"
@@ -33,7 +113,7 @@ func TestAlertProvider_buildHTTPRequestWhenResolved(t *testing.T) {
 	if request.URL.String() != ExpectedURL {
 		t.Error("expected URL to be", ExpectedURL, "was", request.URL.String())
 	}
-	body, _ := ioutil.ReadAll(request.Body)
+	body, _ := io.ReadAll(request.Body)
 	if string(body) != ExpectedBody {
 		t.Error("expected body to be", ExpectedBody, "was", string(body))
 	}
@@ -53,23 +133,12 @@ func TestAlertProvider_buildHTTPRequestWhenTriggered(t *testing.T) {
 	if request.URL.String() != ExpectedURL {
 		t.Error("expected URL to be", ExpectedURL, "was", request.URL.String())
 	}
-	body, _ := ioutil.ReadAll(request.Body)
+	body, _ := io.ReadAll(request.Body)
 	if string(body) != ExpectedBody {
 		t.Error("expected body to be", ExpectedBody, "was", string(body))
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProvider(t *testing.T) {
-	provider := AlertProvider{URL: "https://example.com"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
-	}
-	if customAlertProvider.URL != "https://example.com" {
-		t.Error("expected URL to be https://example.com, got", customAlertProvider.URL)
-	}
-}
-
 func TestAlertProvider_buildHTTPRequestWithCustomPlaceholder(t *testing.T) {
 	const (
 		ExpectedURL  = "https://example.com/endpoint-name?event=test&description=alert-description"
@@ -89,7 +158,7 @@ func TestAlertProvider_buildHTTPRequestWithCustomPlaceholder(t *testing.T) {
 	if request.URL.String() != ExpectedURL {
 		t.Error("expected URL to be", ExpectedURL, "was", request.URL.String())
 	}
-	body, _ := ioutil.ReadAll(request.Body)
+	body, _ := io.ReadAll(request.Body)
 	if string(body) != ExpectedBody {
 		t.Error("expected body to be", ExpectedBody, "was", string(body))
 	}
@@ -110,6 +179,15 @@ func TestAlertProvider_GetAlertStatePlaceholderValueDefaults(t *testing.T) {
 	}
 }
 
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
+	}
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
+	}
+}
+
 // TestAlertProvider_isBackwardCompatibleWithServiceRename checks if the custom alerting provider still supports
 // service placeholders after the migration from "service" to "endpoint"
 //
@@ -127,7 +205,7 @@ func TestAlertProvider_isBackwardCompatibleWithServiceRename(t *testing.T) {
 	if request.URL.String() != ExpectedURL {
 		t.Error("expected URL to be", ExpectedURL, "was", request.URL.String())
 	}
-	body, _ := ioutil.ReadAll(request.Body)
+	body, _ := io.ReadAll(request.Body)
 	if string(body) != ExpectedBody {
 		t.Error("expected body to be", ExpectedBody, "was", string(body))
 	}

alerting/provider/discord/discord.go

@@ -1,11 +1,13 @@
 package discord
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"net/http"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/alerting/provider/custom"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
 )
 
@@ -14,7 +16,7 @@ type AlertProvider struct {
 	WebhookURL string `yaml:"webhook-url"`
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
-	DefaultAlert *alert.Alert `yaml:"default-alert"`
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -22,15 +24,34 @@ func (provider *AlertProvider) IsValid() bool {
 	return len(provider.WebhookURL) > 0
 }
 
-// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
+// Send an alert using the provider
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
+	request, err := http.NewRequest(http.MethodPost, provider.WebhookURL, buffer)
+	if err != nil {
+		return err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	response, err := client.GetHTTPClient(nil).Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+	}
+	return err
+}
+
+// buildRequestBody builds the request body for the provider
+func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
 	var message, results string
 	var colorCode int
 	if resolved {
-		message = fmt.Sprintf("An alert for **%s** has been resolved after passing successfully %d time(s) in a row", endpoint.Name, alert.SuccessThreshold)
+		message = fmt.Sprintf("An alert for **%s** has been resolved after passing successfully %d time(s) in a row", endpoint.DisplayName(), alert.SuccessThreshold)
 		colorCode = 3066993
 	} else {
-		message = fmt.Sprintf("An alert for **%s** has been triggered due to having failed %d time(s) in a row", endpoint.Name, alert.FailureThreshold)
+		message = fmt.Sprintf("An alert for **%s** has been triggered due to having failed %d time(s) in a row", endpoint.DisplayName(), alert.FailureThreshold)
 		colorCode = 15158332
 	}
 	for _, conditionResult := range result.ConditionResults {
@@ -46,10 +67,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
 	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
 		description = ":\\n> " + alertDescription
 	}
-	return &custom.AlertProvider{
-		URL:    provider.WebhookURL,
-		Method: http.MethodPost,
-		Body: fmt.Sprintf(`{
+	return fmt.Sprintf(`{
   "content": "",
   "embeds": [
     {
@@ -65,9 +83,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
       ]
     }
   ]
-}`, message, description, colorCode, results),
-		Headers: map[string]string{"Content-Type": "application/json"},
-	}
+}`, message, description, colorCode, results)
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/discord/discord_test.go

@@ -3,11 +3,12 @@ package discord
 import (
 	"encoding/json"
 	"net/http"
-	"strings"
 	"testing"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -21,50 +22,137 @@ func TestAlertProvider_IsValid(t *testing.T) {
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.com"}
-	alertDescription := "test"
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{Name: "svc"}, &alert.Alert{Description: &alertDescription}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:     "triggered",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "triggered-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+		{
+			Name:     "resolved",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "resolved-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "resolved") {
-		t.Error("customAlertProvider.Body should've contained the substring resolved")
-	}
-	if customAlertProvider.URL != "http://example.com" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
-	}
-	if expected := "An alert for **svc** has been resolved after passing successfully 0 time(s) in a row:\n> test"; expected != body["embeds"].([]interface{})[0].(map[string]interface{})["description"] {
-		t.Errorf("expected $.embeds[0].description to be %s, got %s", expected, body["embeds"].([]interface{})[0].(map[string]interface{})["description"])
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.com"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name         string
+		Provider     AlertProvider
+		Alert        alert.Alert
+		Resolved     bool
+		ExpectedBody string
+	}{
+		{
+			Name:         "triggered",
+			Provider:     AlertProvider{},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "{\n  \"content\": \"\",\n  \"embeds\": [\n    {\n      \"title\": \":helmet_with_white_cross: Gatus\",\n      \"description\": \"An alert for **endpoint-name** has been triggered due to having failed 3 time(s) in a row:\\n> description-1\",\n      \"color\": 15158332,\n      \"fields\": [\n        {\n          \"name\": \"Condition results\",\n          \"value\": \":x: - `[CONNECTED] == true`\\n:x: - `[STATUS] == 200`\\n\",\n          \"inline\": false\n        }\n      ]\n    }\n  ]\n}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\n  \"content\": \"\",\n  \"embeds\": [\n    {\n      \"title\": \":helmet_with_white_cross: Gatus\",\n      \"description\": \"An alert for **endpoint-name** has been resolved after passing successfully 5 time(s) in a row:\\n> description-2\",\n      \"color\": 3066993,\n      \"fields\": [\n        {\n          \"name\": \"Condition results\",\n          \"value\": \":white_check_mark: - `[CONNECTED] == true`\\n:white_check_mark: - `[STATUS] == 200`\\n\",\n          \"inline\": false\n        }\n      ]\n    }\n  ]\n}",
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "triggered") {
-		t.Error("customAlertProvider.Body should've contained the substring triggered")
-	}
-	if customAlertProvider.URL != "http://example.com" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			body := scenario.Provider.buildRequestBody(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected %s, got %s", scenario.ExpectedBody, body)
+			}
+			out := make(map[string]interface{})
+			if err := json.Unmarshal([]byte(body), &out); err != nil {
+				t.Error("expected body to be valid JSON, got error:", err.Error())
+			}
+		})
+	}
+}
+
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
+	}
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
 	}
 }

alerting/provider/email/email.go

@@ -0,0 +1,109 @@
+package email
+
+import (
+	"fmt"
+	"math"
+	"strings"
+
+	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/core"
+	gomail "gopkg.in/mail.v2"
+)
+
+// AlertProvider is the configuration necessary for sending an alert using SMTP
+type AlertProvider struct {
+	From     string `yaml:"from"`
+	Username string `yaml:"username"`
+	Password string `yaml:"password"`
+	Host     string `yaml:"host"`
+	Port     int    `yaml:"port"`
+	To       string `yaml:"to"`
+
+	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
+
+	// Overrides is a list of Override that may be prioritized over the default configuration
+	Overrides []Override `yaml:"overrides,omitempty"`
+}
+
+// Override is a case under which the default integration is overridden
+type Override struct {
+	Group string `yaml:"group"`
+	To    string `yaml:"to"`
+}
+
+// IsValid returns whether the provider's configuration is valid
+func (provider *AlertProvider) IsValid() bool {
+	registeredGroups := make(map[string]bool)
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if isAlreadyRegistered := registeredGroups[override.Group]; isAlreadyRegistered || override.Group == "" || len(override.To) == 0 {
+				return false
+			}
+			registeredGroups[override.Group] = true
+		}
+	}
+
+	return len(provider.From) > 0 && len(provider.Password) > 0 && len(provider.Host) > 0 && len(provider.To) > 0 && provider.Port > 0 && provider.Port < math.MaxUint16
+}
+
+// Send an alert using the provider
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	var username string
+	if len(provider.Username) > 0 {
+		username = provider.Username
+	} else {
+		username = provider.From
+	}
+	subject, body := provider.buildMessageSubjectAndBody(endpoint, alert, result, resolved)
+	m := gomail.NewMessage()
+	m.SetHeader("From", provider.From)
+	m.SetHeader("To", strings.Split(provider.getToForGroup(endpoint.Group), ",")...)
+	m.SetHeader("Subject", subject)
+	m.SetBody("text/plain", body)
+	d := gomail.NewDialer(provider.Host, provider.Port, username, provider.Password)
+	return d.DialAndSend(m)
+}
+
+// buildMessageSubjectAndBody builds the message subject and body
+func (provider *AlertProvider) buildMessageSubjectAndBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) (string, string) {
+	var subject, message, results string
+	if resolved {
+		subject = fmt.Sprintf("[%s] Alert resolved", endpoint.DisplayName())
+		message = fmt.Sprintf("An alert for %s has been resolved after passing successfully %d time(s) in a row", endpoint.DisplayName(), alert.SuccessThreshold)
+	} else {
+		subject = fmt.Sprintf("[%s] Alert triggered", endpoint.DisplayName())
+		message = fmt.Sprintf("An alert for %s has been triggered due to having failed %d time(s) in a row", endpoint.DisplayName(), alert.FailureThreshold)
+	}
+	for _, conditionResult := range result.ConditionResults {
+		var prefix string
+		if conditionResult.Success {
+			prefix = "✅"
+		} else {
+			prefix = "❌"
+		}
+		results += fmt.Sprintf("%s %s\n", prefix, conditionResult.Condition)
+	}
+	var description string
+	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
+		description = "\n\nAlert description: " + alertDescription
+	}
+	return subject, message + description + "\n\nCondition results:\n" + results
+}
+
+// getToForGroup returns the appropriate email integration to for a given group
+func (provider *AlertProvider) getToForGroup(group string) string {
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if group == override.Group {
+				return override.To
+			}
+		}
+	}
+	return provider.To
+}
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/email/email_test.go

@@ -0,0 +1,183 @@
+package email
+
+import (
+	"testing"
+
+	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/core"
+)
+
+func TestAlertDefaultProvider_IsValid(t *testing.T) {
+	invalidProvider := AlertProvider{}
+	if invalidProvider.IsValid() {
+		t.Error("provider shouldn't have been valid")
+	}
+	validProvider := AlertProvider{From: "from@example.com", Password: "password", Host: "smtp.gmail.com", Port: 587, To: "to@example.com"}
+	if !validProvider.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
+func TestAlertProvider_IsValidWithOverride(t *testing.T) {
+	providerWithInvalidOverrideGroup := AlertProvider{
+		Overrides: []Override{
+			{
+				To:    "to@example.com",
+				Group: "",
+			},
+		},
+	}
+	if providerWithInvalidOverrideGroup.IsValid() {
+		t.Error("provider Group shouldn't have been valid")
+	}
+	providerWithInvalidOverrideTo := AlertProvider{
+		Overrides: []Override{
+			{
+				To:    "",
+				Group: "group",
+			},
+		},
+	}
+	if providerWithInvalidOverrideTo.IsValid() {
+		t.Error("provider integration key shouldn't have been valid")
+	}
+	providerWithValidOverride := AlertProvider{
+		From:     "from@example.com",
+		Password: "password",
+		Host:     "smtp.gmail.com",
+		Port:     587,
+		To:       "to@example.com",
+		Overrides: []Override{
+			{
+				To:    "to@example.com",
+				Group: "group",
+			},
+		},
+	}
+	if !providerWithValidOverride.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name            string
+		Provider        AlertProvider
+		Alert           alert.Alert
+		Resolved        bool
+		ExpectedSubject string
+		ExpectedBody    string
+	}{
+		{
+			Name:            "triggered",
+			Provider:        AlertProvider{},
+			Alert:           alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:        false,
+			ExpectedSubject: "[endpoint-name] Alert triggered",
+			ExpectedBody:    "An alert for endpoint-name has been triggered due to having failed 3 time(s) in a row\n\nAlert description: description-1\n\nCondition results:\n❌ [CONNECTED] == true\n❌ [STATUS] == 200\n",
+		},
+		{
+			Name:            "resolved",
+			Provider:        AlertProvider{},
+			Alert:           alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:        true,
+			ExpectedSubject: "[endpoint-name] Alert resolved",
+			ExpectedBody:    "An alert for endpoint-name has been resolved after passing successfully 5 time(s) in a row\n\nAlert description: description-2\n\nCondition results:\n✅ [CONNECTED] == true\n✅ [STATUS] == 200\n",
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			subject, body := scenario.Provider.buildMessageSubjectAndBody(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if subject != scenario.ExpectedSubject {
+				t.Errorf("expected subject to be %s, got %s", scenario.ExpectedSubject, subject)
+			}
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected body to be %s, got %s", scenario.ExpectedBody, body)
+			}
+		})
+	}
+}
+
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
+	}
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
+	}
+}
+
+func TestAlertProvider_getToForGroup(t *testing.T) {
+	tests := []struct {
+		Name           string
+		Provider       AlertProvider
+		InputGroup     string
+		ExpectedOutput string
+	}{
+		{
+			Name: "provider-no-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				To:        "to@example.com",
+				Overrides: nil,
+			},
+			InputGroup:     "",
+			ExpectedOutput: "to@example.com",
+		},
+		{
+			Name: "provider-no-override-specify-group-should-default",
+			Provider: AlertProvider{
+				To:        "to@example.com",
+				Overrides: nil,
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "to@example.com",
+		},
+		{
+			Name: "provider-with-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				To: "to@example.com",
+				Overrides: []Override{
+					{
+						Group: "group",
+						To:    "to01@example.com",
+					},
+				},
+			},
+			InputGroup:     "",
+			ExpectedOutput: "to@example.com",
+		},
+		{
+			Name: "provider-with-override-specify-group-should-override",
+			Provider: AlertProvider{
+				To: "to@example.com",
+				Overrides: []Override{
+					{
+						Group: "group",
+						To:    "to01@example.com",
+					},
+				},
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "to01@example.com",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.Name, func(t *testing.T) {
+			if got := tt.Provider.getToForGroup(tt.InputGroup); got != tt.ExpectedOutput {
+				t.Errorf("AlertProvider.getToForGroup() = %v, want %v", got, tt.ExpectedOutput)
+			}
+		})
+	}
+}

alerting/provider/googlechat/googlechat.go

@@ -0,0 +1,124 @@
+package googlechat
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/http"
+
+	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
+	"github.com/TwiN/gatus/v3/core"
+)
+
+// AlertProvider is the configuration necessary for sending an alert using Google chat
+type AlertProvider struct {
+	WebhookURL string `yaml:"webhook-url"`
+
+	// ClientConfig is the configuration of the client used to communicate with the provider's target
+	ClientConfig *client.Config `yaml:"client,omitempty"`
+
+	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
+}
+
+// IsValid returns whether the provider's configuration is valid
+func (provider *AlertProvider) IsValid() bool {
+	if provider.ClientConfig == nil {
+		provider.ClientConfig = client.GetDefaultConfig()
+	}
+	return len(provider.WebhookURL) > 0
+}
+
+// Send an alert using the provider
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
+	request, err := http.NewRequest(http.MethodPost, provider.WebhookURL, buffer)
+	if err != nil {
+		return err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	response, err := client.GetHTTPClient(provider.ClientConfig).Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+	}
+	return err
+}
+
+// buildRequestBody builds the request body for the provider
+func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
+	var message, color string
+	if resolved {
+		color = "#36A64F"
+		message = fmt.Sprintf("<font color='%s'>An alert has been resolved after passing successfully %d time(s) in a row</font>", color, alert.SuccessThreshold)
+	} else {
+		color = "#DD0000"
+		message = fmt.Sprintf("<font color='%s'>An alert has been triggered due to having failed %d time(s) in a row</font>", color, alert.FailureThreshold)
+	}
+	var results string
+	for _, conditionResult := range result.ConditionResults {
+		var prefix string
+		if conditionResult.Success {
+			prefix = "✅"
+		} else {
+			prefix = "❌"
+		}
+		results += fmt.Sprintf("%s   %s<br>", prefix, conditionResult.Condition)
+	}
+	var description string
+	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
+		description = ":: " + alertDescription
+	}
+	return fmt.Sprintf(`{
+    "cards": [
+  {
+    "sections": [
+      {
+        "widgets": [
+          {
+            "keyValue": {
+              "topLabel": "%s [%s]",
+              "content": "%s",
+              "contentMultiline": "true",
+              "bottomLabel": "%s",
+              "icon": "BOOKMARK"
+            }
+          },
+          {
+            "keyValue": {
+              "topLabel": "Condition results",
+              "content": "%s",
+              "contentMultiline": "true",
+              "icon": "DESCRIPTION"
+            }
+          },
+          {
+            "buttons": [
+              {
+                "textButton": {
+                  "text": "URL",
+                  "onClick": {
+                    "openLink": {
+                      "url": "%s"
+                    }
+                  }
+                }
+              }
+            ]
+          }
+        ]
+      }
+    ]
+  }
+]
+}`, endpoint.Name, endpoint.Group, message, description, results, endpoint.URL)
+}
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/googlechat/googlechat_test.go

@@ -0,0 +1,160 @@
+package googlechat
+
+import (
+	"encoding/json"
+	"net/http"
+	"testing"
+
+	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
+	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
+)
+
+func TestAlertProvider_IsValid(t *testing.T) {
+	invalidProvider := AlertProvider{WebhookURL: ""}
+	if invalidProvider.IsValid() {
+		t.Error("provider shouldn't have been valid")
+	}
+	validProvider := AlertProvider{WebhookURL: "http://example.com"}
+	if !validProvider.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:     "triggered",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "triggered-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+		{
+			Name:     "resolved",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "resolved-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "endpoint-name", Group: "endpoint-group"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
+	}
+}
+
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name         string
+		Provider     AlertProvider
+		Alert        alert.Alert
+		Resolved     bool
+		ExpectedBody string
+	}{
+		{
+			Name:         "triggered",
+			Provider:     AlertProvider{},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "{\n    \"cards\": [\n  {\n    \"sections\": [\n      {\n        \"widgets\": [\n          {\n            \"keyValue\": {\n              \"topLabel\": \"endpoint-name []\",\n              \"content\": \"\u003cfont color='#DD0000'\u003eAn alert has been triggered due to having failed 3 time(s) in a row\u003c/font\u003e\",\n              \"contentMultiline\": \"true\",\n              \"bottomLabel\": \":: description-1\",\n              \"icon\": \"BOOKMARK\"\n            }\n          },\n          {\n            \"keyValue\": {\n              \"topLabel\": \"Condition results\",\n              \"content\": \"❌   [CONNECTED] == true\u003cbr\u003e❌   [STATUS] == 200\u003cbr\u003e\",\n              \"contentMultiline\": \"true\",\n              \"icon\": \"DESCRIPTION\"\n            }\n          },\n          {\n            \"buttons\": [\n              {\n                \"textButton\": {\n                  \"text\": \"URL\",\n                  \"onClick\": {\n                    \"openLink\": {\n                      \"url\": \"\"\n                    }\n                  }\n                }\n              }\n            ]\n          }\n        ]\n      }\n    ]\n  }\n]\n}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\n    \"cards\": [\n  {\n    \"sections\": [\n      {\n        \"widgets\": [\n          {\n            \"keyValue\": {\n              \"topLabel\": \"endpoint-name []\",\n              \"content\": \"\u003cfont color='#36A64F'\u003eAn alert has been resolved after passing successfully 5 time(s) in a row\u003c/font\u003e\",\n              \"contentMultiline\": \"true\",\n              \"bottomLabel\": \":: description-2\",\n              \"icon\": \"BOOKMARK\"\n            }\n          },\n          {\n            \"keyValue\": {\n              \"topLabel\": \"Condition results\",\n              \"content\": \"✅   [CONNECTED] == true\u003cbr\u003e✅   [STATUS] == 200\u003cbr\u003e\",\n              \"contentMultiline\": \"true\",\n              \"icon\": \"DESCRIPTION\"\n            }\n          },\n          {\n            \"buttons\": [\n              {\n                \"textButton\": {\n                  \"text\": \"URL\",\n                  \"onClick\": {\n                    \"openLink\": {\n                      \"url\": \"\"\n                    }\n                  }\n                }\n              }\n            ]\n          }\n        ]\n      }\n    ]\n  }\n]\n}",
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			body := scenario.Provider.buildRequestBody(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			b, _ := json.Marshal(body)
+			e, _ := json.Marshal(scenario.ExpectedBody)
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected %s, got %s", e, b)
+			}
+			out := make(map[string]interface{})
+			if err := json.Unmarshal([]byte(body), &out); err != nil {
+				t.Error("expected body to be valid JSON, got error:", err.Error())
+			}
+		})
+	}
+}
+
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
+	}
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
+	}
+}

alerting/provider/mattermost/mattermost.go

@@ -1,11 +1,12 @@
 package mattermost
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"net/http"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/alerting/provider/custom"
 	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
 )
@@ -15,10 +16,10 @@ type AlertProvider struct {
 	WebhookURL string `yaml:"webhook-url"`
 
 	// ClientConfig is the configuration of the client used to communicate with the provider's target
-	ClientConfig *client.Config `yaml:"client"`
+	ClientConfig *client.Config `yaml:"client,omitempty"`
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
-	DefaultAlert *alert.Alert `yaml:"default-alert"`
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -29,15 +30,33 @@ func (provider *AlertProvider) IsValid() bool {
 	return len(provider.WebhookURL) > 0
 }
 
-// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
-	var message string
-	var color string
+// Send an alert using the provider
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
+	request, err := http.NewRequest(http.MethodPost, provider.WebhookURL, buffer)
+	if err != nil {
+		return err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	response, err := client.GetHTTPClient(provider.ClientConfig).Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+	}
+	return err
+}
+
+// buildRequestBody builds the request body for the provider
+func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
+	var message, color string
 	if resolved {
-		message = fmt.Sprintf("An alert for *%s* has been resolved after passing successfully %d time(s) in a row", endpoint.Name, alert.SuccessThreshold)
+		message = fmt.Sprintf("An alert for *%s* has been resolved after passing successfully %d time(s) in a row", endpoint.DisplayName(), alert.SuccessThreshold)
 		color = "#36A64F"
 	} else {
-		message = fmt.Sprintf("An alert for *%s* has been triggered due to having failed %d time(s) in a row", endpoint.Name, alert.FailureThreshold)
+		message = fmt.Sprintf("An alert for *%s* has been triggered due to having failed %d time(s) in a row", endpoint.DisplayName(), alert.FailureThreshold)
 		color = "#DD0000"
 	}
 	var results string
@@ -54,14 +73,10 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
 	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
 		description = ":\\n> " + alertDescription
 	}
-	return &custom.AlertProvider{
-		URL:          provider.WebhookURL,
-		Method:       http.MethodPost,
-		ClientConfig: provider.ClientConfig,
-		Body: fmt.Sprintf(`{
+	return fmt.Sprintf(`{
   "text": "",
   "username": "gatus",
-  "icon_url": "https://raw.githubusercontent.com/TwiN/gatus/master/static/logo.png",
+  "icon_url": "https://raw.githubusercontent.com/TwiN/gatus/master/.github/assets/logo.png",
   "attachments": [
     {
       "title": ":rescue_worker_helmet: Gatus",
@@ -83,9 +98,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
       ]
     }
   ]
-}`, message, message, description, color, endpoint.URL, results),
-		Headers: map[string]string{"Content-Type": "application/json"},
-	}
+}`, message, message, description, color, endpoint.URL, results)
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/mattermost/mattermost_test.go

@@ -3,11 +3,12 @@ package mattermost
 import (
 	"encoding/json"
 	"net/http"
-	"strings"
 	"testing"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -21,50 +22,137 @@ func TestAlertProvider_IsValid(t *testing.T) {
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.org"}
-	alertDescription := "test"
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{Name: "svc"}, &alert.Alert{Description: &alertDescription}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:     "triggered",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "triggered-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+		{
+			Name:     "resolved",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "resolved-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "resolved") {
-		t.Error("customAlertProvider.Body should've contained the substring resolved")
-	}
-	if customAlertProvider.URL != "http://example.org" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
-	}
-	if expected := "An alert for *svc* has been resolved after passing successfully 0 time(s) in a row:\n> test"; expected != body["attachments"].([]interface{})[0].(map[string]interface{})["text"] {
-		t.Errorf("expected $.attachments[0].description to be %s, got %s", expected, body["attachments"].([]interface{})[0].(map[string]interface{})["text"])
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.org"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name         string
+		Provider     AlertProvider
+		Alert        alert.Alert
+		Resolved     bool
+		ExpectedBody string
+	}{
+		{
+			Name:         "triggered",
+			Provider:     AlertProvider{},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "{\n  \"text\": \"\",\n  \"username\": \"gatus\",\n  \"icon_url\": \"https://raw.githubusercontent.com/TwiN/gatus/master/.github/assets/logo.png\",\n  \"attachments\": [\n    {\n      \"title\": \":rescue_worker_helmet: Gatus\",\n      \"fallback\": \"Gatus - An alert for *endpoint-name* has been triggered due to having failed 3 time(s) in a row\",\n      \"text\": \"An alert for *endpoint-name* has been triggered due to having failed 3 time(s) in a row:\\n> description-1\",\n      \"short\": false,\n      \"color\": \"#DD0000\",\n      \"fields\": [\n        {\n          \"title\": \"URL\",\n          \"value\": \"\",\n          \"short\": false\n        },\n        {\n          \"title\": \"Condition results\",\n          \"value\": \":x: - `[CONNECTED] == true`\\n:x: - `[STATUS] == 200`\\n\",\n          \"short\": false\n        }\n      ]\n    }\n  ]\n}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\n  \"text\": \"\",\n  \"username\": \"gatus\",\n  \"icon_url\": \"https://raw.githubusercontent.com/TwiN/gatus/master/.github/assets/logo.png\",\n  \"attachments\": [\n    {\n      \"title\": \":rescue_worker_helmet: Gatus\",\n      \"fallback\": \"Gatus - An alert for *endpoint-name* has been resolved after passing successfully 5 time(s) in a row\",\n      \"text\": \"An alert for *endpoint-name* has been resolved after passing successfully 5 time(s) in a row:\\n> description-2\",\n      \"short\": false,\n      \"color\": \"#36A64F\",\n      \"fields\": [\n        {\n          \"title\": \"URL\",\n          \"value\": \"\",\n          \"short\": false\n        },\n        {\n          \"title\": \"Condition results\",\n          \"value\": \":white_check_mark: - `[CONNECTED] == true`\\n:white_check_mark: - `[STATUS] == 200`\\n\",\n          \"short\": false\n        }\n      ]\n    }\n  ]\n}",
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "triggered") {
-		t.Error("customAlertProvider.Body should've contained the substring triggered")
-	}
-	if customAlertProvider.URL != "http://example.org" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			body := scenario.Provider.buildRequestBody(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected %s, got %s", scenario.ExpectedBody, body)
+			}
+			out := make(map[string]interface{})
+			if err := json.Unmarshal([]byte(body), &out); err != nil {
+				t.Error("expected body to be valid JSON, got error:", err.Error())
+			}
+		})
+	}
+}
+
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
+	}
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
 	}
 }

alerting/provider/messagebird/messagebird.go

@@ -1,11 +1,13 @@
 package messagebird
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"net/http"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/alerting/provider/custom"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
 )
 
@@ -20,7 +22,7 @@ type AlertProvider struct {
 	Recipients string `yaml:"recipients"`
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
-	DefaultAlert *alert.Alert `yaml:"default-alert"`
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -28,28 +30,40 @@ func (provider *AlertProvider) IsValid() bool {
 	return len(provider.AccessKey) > 0 && len(provider.Originator) > 0 && len(provider.Recipients) > 0
 }
 
-// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-// Reference doc for messagebird https://developers.messagebird.com/api/sms-messaging/#send-outbound-sms
-func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, _ *core.Result, resolved bool) *custom.AlertProvider {
+// Send an alert using the provider
+// Reference doc for messagebird: https://developers.messagebird.com/api/sms-messaging/#send-outbound-sms
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
+	request, err := http.NewRequest(http.MethodPost, restAPIURL, buffer)
+	if err != nil {
+		return err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	request.Header.Set("Authorization", fmt.Sprintf("AccessKey %s", provider.AccessKey))
+	response, err := client.GetHTTPClient(nil).Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+	}
+	return err
+}
+
+// buildRequestBody builds the request body for the provider
+func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
 	var message string
 	if resolved {
-		message = fmt.Sprintf("RESOLVED: %s - %s", endpoint.Name, alert.GetDescription())
+		message = fmt.Sprintf("RESOLVED: %s - %s", endpoint.DisplayName(), alert.GetDescription())
 	} else {
-		message = fmt.Sprintf("TRIGGERED: %s - %s", endpoint.Name, alert.GetDescription())
+		message = fmt.Sprintf("TRIGGERED: %s - %s", endpoint.DisplayName(), alert.GetDescription())
 	}
-	return &custom.AlertProvider{
-		URL:    restAPIURL,
-		Method: http.MethodPost,
-		Body: fmt.Sprintf(`{
+	return fmt.Sprintf(`{
   "originator": "%s",
   "recipients": "%s",
   "body": "%s"
-}`, provider.Originator, provider.Recipients, message),
-		Headers: map[string]string{
-			"Content-Type":  "application/json",
-			"Authorization": fmt.Sprintf("AccessKey %s", provider.AccessKey),
-		},
-	}
+}`, provider.Originator, provider.Recipients, message)
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/messagebird/messagebird_test.go

@@ -3,11 +3,12 @@ package messagebird
 import (
 	"encoding/json"
 	"net/http"
-	"strings"
 	"testing"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
 )
 
 func TestMessagebirdAlertProvider_IsValid(t *testing.T) {
@@ -25,54 +26,137 @@ func TestMessagebirdAlertProvider_IsValid(t *testing.T) {
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{
-		AccessKey:  "1",
-		Originator: "1",
-		Recipients: "1",
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:     "triggered",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "triggered-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+		{
+			Name:     "resolved",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "resolved-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
-	}
-	if !strings.Contains(customAlertProvider.Body, "RESOLVED") {
-		t.Error("customAlertProvider.Body should've contained the substring RESOLVED")
-	}
-	if customAlertProvider.URL != "https://rest.messagebird.com/messages" {
-		t.Errorf("expected URL to be %s, got %s", "https://rest.messagebird.com/messages", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{
-		AccessKey:  "1",
-		Originator: "1",
-		Recipients: "1",
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name         string
+		Provider     AlertProvider
+		Alert        alert.Alert
+		Resolved     bool
+		ExpectedBody string
+	}{
+		{
+			Name:         "triggered",
+			Provider:     AlertProvider{AccessKey: "1", Originator: "2", Recipients: "3"},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "{\n  \"originator\": \"2\",\n  \"recipients\": \"3\",\n  \"body\": \"TRIGGERED: endpoint-name - description-1\"\n}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{AccessKey: "4", Originator: "5", Recipients: "6"},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\n  \"originator\": \"5\",\n  \"recipients\": \"6\",\n  \"body\": \"RESOLVED: endpoint-name - description-2\"\n}",
+		},
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
-	}
-	if !strings.Contains(customAlertProvider.Body, "TRIGGERED") {
-		t.Error("customAlertProvider.Body should've contained the substring TRIGGERED")
-	}
-	if customAlertProvider.URL != "https://rest.messagebird.com/messages" {
-		t.Errorf("expected URL to be %s, got %s", "https://rest.messagebird.com/messages", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			body := scenario.Provider.buildRequestBody(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected %s, got %s", scenario.ExpectedBody, body)
+			}
+			out := make(map[string]interface{})
+			if err := json.Unmarshal([]byte(body), &out); err != nil {
+				t.Error("expected body to be valid JSON, got error:", err.Error())
+			}
+		})
+	}
+}
+
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
+	}
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
 	}
 }

alerting/provider/opsgenie/opsgenie.go

@@ -0,0 +1,240 @@
+package opsgenie
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
+	"github.com/TwiN/gatus/v3/core"
+)
+
+const (
+	restAPI = "https://api.opsgenie.com/v2/alerts"
+)
+
+type AlertProvider struct {
+	// APIKey to use for
+	APIKey string `yaml:"api-key"`
+
+	// Priority to be used in Opsgenie alert payload
+	//
+	// default: P1
+	Priority string `yaml:"priority"`
+
+	// Source define source to be used in Opsgenie alert payload
+	//
+	// default: gatus
+	Source string `yaml:"source"`
+
+	// EntityPrefix is a prefix to be used in entity argument in Opsgenie alert payload
+	//
+	// default: gatus-
+	EntityPrefix string `yaml:"entity-prefix"`
+
+	//AliasPrefix is a prefix to be used in alias argument in Opsgenie alert payload
+	//
+	// default: gatus-healthcheck-
+	AliasPrefix string `yaml:"alias-prefix"`
+
+	// Tags to be used in Opsgenie alert payload
+	//
+	// default: []
+	Tags []string `yaml:"tags"`
+
+	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
+}
+
+// IsValid returns whether the provider's configuration is valid
+func (provider *AlertProvider) IsValid() bool {
+	return len(provider.APIKey) > 0
+}
+
+// Send an alert using the provider
+//
+// Relevant: https://docs.opsgenie.com/docs/alert-api
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	err := provider.createAlert(endpoint, alert, result, resolved)
+	if err != nil {
+		return err
+	}
+	if resolved {
+		err = provider.closeAlert(endpoint, alert)
+		if err != nil {
+			return err
+		}
+	}
+	if alert.IsSendingOnResolved() {
+		if resolved {
+			// The alert has been resolved and there's no error, so we can clear the alert's ResolveKey
+			alert.ResolveKey = ""
+		} else {
+			alert.ResolveKey = provider.alias(buildKey(endpoint))
+		}
+	}
+	return nil
+}
+
+func (provider *AlertProvider) createAlert(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	payload := provider.buildCreateRequestBody(endpoint, alert, result, resolved)
+	_, err := provider.sendRequest(restAPI, http.MethodPost, payload)
+	return err
+}
+
+func (provider *AlertProvider) closeAlert(endpoint *core.Endpoint, alert *alert.Alert) error {
+	payload := provider.buildCloseRequestBody(endpoint, alert)
+	url := restAPI + "/" + provider.alias(buildKey(endpoint)) + "/close?identifierType=alias"
+	_, err := provider.sendRequest(url, http.MethodPost, payload)
+	return err
+}
+
+func (provider *AlertProvider) sendRequest(url, method string, payload interface{}) (*http.Response, error) {
+	body, err := json.Marshal(payload)
+	if err != nil {
+		return nil, fmt.Errorf("fail to build alert payload: %v", payload)
+	}
+	request, err := http.NewRequest(method, url, bytes.NewBuffer(body))
+	if err != nil {
+		return nil, err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	request.Header.Set("Authorization", "GenieKey "+provider.APIKey)
+	res, err := client.GetHTTPClient(nil).Do(request)
+	if err != nil {
+		return nil, err
+	}
+	if res.StatusCode > 399 {
+		rBody, _ := io.ReadAll(res.Body)
+		return nil, fmt.Errorf("call to provider alert returned status code %d: %s", res.StatusCode, string(rBody))
+	}
+	return res, nil
+}
+
+func (provider *AlertProvider) buildCreateRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) alertCreateRequest {
+	var message, description, results string
+	if resolved {
+		message = fmt.Sprintf("RESOLVED: %s - %s", endpoint.Name, alert.GetDescription())
+		description = fmt.Sprintf("An alert for *%s* has been resolved after passing successfully %d time(s) in a row", endpoint.DisplayName(), alert.SuccessThreshold)
+	} else {
+		message = fmt.Sprintf("%s - %s", endpoint.Name, alert.GetDescription())
+		description = fmt.Sprintf("An alert for *%s* has been triggered due to having failed %d time(s) in a row", endpoint.DisplayName(), alert.FailureThreshold)
+	}
+	if endpoint.Group != "" {
+		message = fmt.Sprintf("[%s] %s", endpoint.Group, message)
+	}
+	for _, conditionResult := range result.ConditionResults {
+		var prefix string
+		if conditionResult.Success {
+			prefix = "▣"
+		} else {
+			prefix = "▢"
+		}
+		results += fmt.Sprintf("%s - `%s`\n", prefix, conditionResult.Condition)
+	}
+	description = description + "\n" + results
+	key := buildKey(endpoint)
+	details := map[string]string{
+		"endpoint:url":    endpoint.URL,
+		"endpoint:group":  endpoint.Group,
+		"result:hostname": result.Hostname,
+		"result:ip":       result.IP,
+		"result:dns_code": result.DNSRCode,
+		"result:errors":   strings.Join(result.Errors, ","),
+	}
+	for k, v := range details {
+		if v == "" {
+			delete(details, k)
+		}
+	}
+	if result.HTTPStatus > 0 {
+		details["result:http_status"] = strconv.Itoa(result.HTTPStatus)
+	}
+	return alertCreateRequest{
+		Message:     message,
+		Description: description,
+		Source:      provider.source(),
+		Priority:    provider.priority(),
+		Alias:       provider.alias(key),
+		Entity:      provider.entity(key),
+		Tags:        provider.Tags,
+		Details:     details,
+	}
+}
+
+func (provider *AlertProvider) buildCloseRequestBody(endpoint *core.Endpoint, alert *alert.Alert) alertCloseRequest {
+	return alertCloseRequest{
+		Source: buildKey(endpoint),
+		Note:   fmt.Sprintf("RESOLVED: %s - %s", endpoint.Name, alert.GetDescription()),
+	}
+}
+
+func (provider *AlertProvider) source() string {
+	source := provider.Source
+	if source == "" {
+		return "gatus"
+	}
+	return source
+}
+
+func (provider *AlertProvider) alias(key string) string {
+	alias := provider.AliasPrefix
+	if alias == "" {
+		alias = "gatus-healthcheck-"
+	}
+	return alias + key
+}
+
+func (provider *AlertProvider) entity(key string) string {
+	alias := provider.EntityPrefix
+	if alias == "" {
+		alias = "gatus-"
+	}
+	return alias + key
+}
+
+func (provider *AlertProvider) priority() string {
+	priority := provider.Priority
+	if priority == "" {
+		return "P1"
+	}
+	return priority
+}
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}
+
+func buildKey(endpoint *core.Endpoint) string {
+	name := toKebabCase(endpoint.Name)
+	if endpoint.Group == "" {
+		return name
+	}
+	return toKebabCase(endpoint.Group) + "-" + name
+}
+
+func toKebabCase(val string) string {
+	return strings.ToLower(strings.ReplaceAll(val, " ", "-"))
+}
+
+type alertCreateRequest struct {
+	Message     string            `json:"message"`
+	Priority    string            `json:"priority"`
+	Source      string            `json:"source"`
+	Entity      string            `json:"entity"`
+	Alias       string            `json:"alias"`
+	Description string            `json:"description"`
+	Tags        []string          `json:"tags,omitempty"`
+	Details     map[string]string `json:"details"`
+}
+
+type alertCloseRequest struct {
+	Source string `json:"source"`
+	Note   string `json:"note"`
+}

alerting/provider/opsgenie/opsgenie_test.go

@@ -0,0 +1,319 @@
+package opsgenie
+
+import (
+	"net/http"
+	"reflect"
+	"testing"
+
+	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
+	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
+)
+
+func TestAlertProvider_IsValid(t *testing.T) {
+	invalidProvider := AlertProvider{APIKey: ""}
+	if invalidProvider.IsValid() {
+		t.Error("provider shouldn't have been valid")
+	}
+	validProvider := AlertProvider{APIKey: "00000000-0000-0000-0000-000000000000"}
+	if !validProvider.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	description := "my bad alert description"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:          "triggered",
+			Provider:      AlertProvider{},
+			Alert:         alert.Alert{Description: &description, SuccessThreshold: 1, FailureThreshold: 1},
+			Resolved:      false,
+			ExpectedError: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+		},
+		{
+			Name:          "triggered-error",
+			Provider:      AlertProvider{},
+			Alert:         alert.Alert{Description: &description, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:      false,
+			ExpectedError: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+		},
+		{
+			Name:          "resolved",
+			Provider:      AlertProvider{},
+			Alert:         alert.Alert{Description: &description, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:      true,
+			ExpectedError: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+		},
+		{
+			Name:          "resolved-error",
+			Provider:      AlertProvider{},
+			Alert:         alert.Alert{Description: &description, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:      true,
+			ExpectedError: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+		},
+	}
+
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
+	}
+}
+
+func TestAlertProvider_buildCreateRequestBody(t *testing.T) {
+	t.Parallel()
+	description := "alert description"
+	scenarios := []struct {
+		Name     string
+		Provider *AlertProvider
+		Alert    *alert.Alert
+		Endpoint *core.Endpoint
+		Result   *core.Result
+		Resolved bool
+		want     alertCreateRequest
+	}{
+		{
+			Name:     "missing all params (unresolved)",
+			Provider: &AlertProvider{},
+			Alert:    &alert.Alert{},
+			Endpoint: &core.Endpoint{},
+			Result:   &core.Result{},
+			Resolved: false,
+			want: alertCreateRequest{
+				Message:     " - ",
+				Priority:    "P1",
+				Source:      "gatus",
+				Entity:      "gatus-",
+				Alias:       "gatus-healthcheck-",
+				Description: "An alert for ** has been triggered due to having failed 0 time(s) in a row\n",
+				Tags:        nil,
+				Details:     map[string]string{},
+			},
+		},
+		{
+			Name:     "missing all params (resolved)",
+			Provider: &AlertProvider{},
+			Alert:    &alert.Alert{},
+			Endpoint: &core.Endpoint{},
+			Result:   &core.Result{},
+			Resolved: true,
+			want: alertCreateRequest{
+				Message:     "RESOLVED:  - ",
+				Priority:    "P1",
+				Source:      "gatus",
+				Entity:      "gatus-",
+				Alias:       "gatus-healthcheck-",
+				Description: "An alert for ** has been resolved after passing successfully 0 time(s) in a row\n",
+				Tags:        nil,
+				Details:     map[string]string{},
+			},
+		},
+		{
+			Name:     "with default options (unresolved)",
+			Provider: &AlertProvider{},
+			Alert: &alert.Alert{
+				Description:      &description,
+				FailureThreshold: 3,
+			},
+			Endpoint: &core.Endpoint{
+				Name: "my super app",
+			},
+			Result: &core.Result{
+				ConditionResults: []*core.ConditionResult{
+					{
+						Condition: "[STATUS] == 200",
+						Success:   true,
+					},
+					{
+						Condition: "[BODY] == OK",
+						Success:   false,
+					},
+				},
+			},
+			Resolved: false,
+			want: alertCreateRequest{
+				Message:     "my super app - " + description,
+				Priority:    "P1",
+				Source:      "gatus",
+				Entity:      "gatus-my-super-app",
+				Alias:       "gatus-healthcheck-my-super-app",
+				Description: "An alert for *my super app* has been triggered due to having failed 3 time(s) in a row\n▣ - `[STATUS] == 200`\n▢ - `[BODY] == OK`\n",
+				Tags:        nil,
+				Details:     map[string]string{},
+			},
+		},
+		{
+			Name: "with custom options (resolved)",
+			Provider: &AlertProvider{
+				Priority:     "P5",
+				EntityPrefix: "oompa-",
+				AliasPrefix:  "loompa-",
+				Source:       "gatus-hc",
+				Tags:         []string{"do-ba-dee-doo"},
+			},
+			Alert: &alert.Alert{
+				Description:      &description,
+				SuccessThreshold: 4,
+			},
+			Endpoint: &core.Endpoint{
+				Name: "my mega app",
+			},
+			Result: &core.Result{
+				ConditionResults: []*core.ConditionResult{
+					{
+						Condition: "[STATUS] == 200",
+						Success:   true,
+					},
+				},
+			},
+			Resolved: true,
+			want: alertCreateRequest{
+				Message:     "RESOLVED: my mega app - " + description,
+				Priority:    "P5",
+				Source:      "gatus-hc",
+				Entity:      "oompa-my-mega-app",
+				Alias:       "loompa-my-mega-app",
+				Description: "An alert for *my mega app* has been resolved after passing successfully 4 time(s) in a row\n▣ - `[STATUS] == 200`\n",
+				Tags:        []string{"do-ba-dee-doo"},
+				Details:     map[string]string{},
+			},
+		},
+		{
+			Name: "with default options and details (unresolved)",
+			Provider: &AlertProvider{
+				Tags: []string{"foo"},
+			},
+			Alert: &alert.Alert{
+				Description:      &description,
+				FailureThreshold: 6,
+			},
+			Endpoint: &core.Endpoint{
+				Name:  "my app",
+				Group: "end game",
+				URL:   "https://my.go/app",
+			},
+			Result: &core.Result{
+				HTTPStatus: 400,
+				Hostname:   "my.go",
+				Errors:     []string{"error 01", "error 02"},
+				Success:    false,
+				ConditionResults: []*core.ConditionResult{
+					{
+						Condition: "[STATUS] == 200",
+						Success:   false,
+					},
+				},
+			},
+			Resolved: false,
+			want: alertCreateRequest{
+				Message:     "[end game] my app - " + description,
+				Priority:    "P1",
+				Source:      "gatus",
+				Entity:      "gatus-end-game-my-app",
+				Alias:       "gatus-healthcheck-end-game-my-app",
+				Description: "An alert for *end game/my app* has been triggered due to having failed 6 time(s) in a row\n▢ - `[STATUS] == 200`\n",
+				Tags:        []string{"foo"},
+				Details: map[string]string{
+					"endpoint:url":       "https://my.go/app",
+					"endpoint:group":     "end game",
+					"result:hostname":    "my.go",
+					"result:errors":      "error 01,error 02",
+					"result:http_status": "400",
+				},
+			},
+		},
+	}
+	for _, scenario := range scenarios {
+		actual := scenario
+		t.Run(actual.Name, func(t *testing.T) {
+			if got := actual.Provider.buildCreateRequestBody(actual.Endpoint, actual.Alert, actual.Result, actual.Resolved); !reflect.DeepEqual(got, actual.want) {
+				t.Errorf("buildCreateRequestBody() = %v, want %v", got, actual.want)
+			}
+		})
+	}
+}
+
+func TestAlertProvider_buildCloseRequestBody(t *testing.T) {
+	t.Parallel()
+	description := "alert description"
+	scenarios := []struct {
+		Name     string
+		Provider *AlertProvider
+		Alert    *alert.Alert
+		Endpoint *core.Endpoint
+		want     alertCloseRequest
+	}{
+		{
+			Name:     "Missing all values",
+			Provider: &AlertProvider{},
+			Alert:    &alert.Alert{},
+			Endpoint: &core.Endpoint{},
+			want: alertCloseRequest{
+				Source: "",
+				Note:   "RESOLVED:  - ",
+			},
+		},
+		{
+			Name:     "Basic values",
+			Provider: &AlertProvider{},
+			Alert: &alert.Alert{
+				Description: &description,
+			},
+			Endpoint: &core.Endpoint{
+				Name: "endpoint name",
+			},
+			want: alertCloseRequest{
+				Source: "endpoint-name",
+				Note:   "RESOLVED: endpoint name - alert description",
+			},
+		},
+	}
+
+	for _, scenario := range scenarios {
+		actual := scenario
+		t.Run(actual.Name, func(t *testing.T) {
+			if got := actual.Provider.buildCloseRequestBody(actual.Endpoint, actual.Alert); !reflect.DeepEqual(got, actual.want) {
+				t.Errorf("buildCloseRequestBody() = %v, want %v", got, actual.want)
+			}
+		})
+	}
+}

alerting/provider/pagerduty/pagerduty.go

@@ -1,11 +1,15 @@
 package pagerduty
 
 import (
+	"bytes"
+	"encoding/json"
 	"fmt"
+	"io"
+	"log"
 	"net/http"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/alerting/provider/custom"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
 )
 
@@ -18,10 +22,10 @@ type AlertProvider struct {
 	IntegrationKey string `yaml:"integration-key"`
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
-	DefaultAlert *alert.Alert `yaml:"default-alert"`
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
 
 	// Overrides is a list of Override that may be prioritized over the default configuration
-	Overrides []Override `yaml:"overrides"`
+	Overrides []Override `yaml:"overrides,omitempty"`
 }
 
 // Override is a case under which the default integration is overridden
@@ -45,24 +49,56 @@ func (provider *AlertProvider) IsValid() bool {
 	return len(provider.IntegrationKey) == 32 || len(provider.Overrides) != 0
 }
 
-// ToCustomAlertProvider converts the provider into a custom.AlertProvider
+// Send an alert using the provider
 //
-// relevant: https://developer.pagerduty.com/docs/events-api-v2/trigger-events/
-func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, _ *core.Result, resolved bool) *custom.AlertProvider {
+// Relevant: https://developer.pagerduty.com/docs/events-api-v2/trigger-events/
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
+	request, err := http.NewRequest(http.MethodPost, restAPIURL, buffer)
+	if err != nil {
+		return err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	response, err := client.GetHTTPClient(nil).Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+	}
+	if alert.IsSendingOnResolved() {
+		if resolved {
+			// The alert has been resolved and there's no error, so we can clear the alert's ResolveKey
+			alert.ResolveKey = ""
+		} else {
+			// We need to retrieve the resolve key from the response
+			body, err := io.ReadAll(response.Body)
+			var payload pagerDutyResponsePayload
+			if err = json.Unmarshal(body, &payload); err != nil {
+				// Silently fail. We don't want to create tons of alerts just because we failed to parse the body.
+				log.Printf("[pagerduty][Send] Ran into error unmarshaling pagerduty response: %s", err.Error())
+			} else {
+				alert.ResolveKey = payload.DedupKey
+			}
+		}
+	}
+	return nil
+}
+
+// buildRequestBody builds the request body for the provider
+func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
 	var message, eventAction, resolveKey string
 	if resolved {
-		message = fmt.Sprintf("RESOLVED: %s - %s", endpoint.Name, alert.GetDescription())
+		message = fmt.Sprintf("RESOLVED: %s - %s", endpoint.DisplayName(), alert.GetDescription())
 		eventAction = "resolve"
 		resolveKey = alert.ResolveKey
 	} else {
-		message = fmt.Sprintf("TRIGGERED: %s - %s", endpoint.Name, alert.GetDescription())
+		message = fmt.Sprintf("TRIGGERED: %s - %s", endpoint.DisplayName(), alert.GetDescription())
 		eventAction = "trigger"
 		resolveKey = ""
 	}
-	return &custom.AlertProvider{
-		URL:    restAPIURL,
-		Method: http.MethodPost,
-		Body: fmt.Sprintf(`{
+	return fmt.Sprintf(`{
   "routing_key": "%s",
   "dedup_key": "%s",
   "event_action": "%s",
@@ -71,11 +107,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
     "source": "%s",
     "severity": "critical"
   }
-}`, provider.getIntegrationKeyForGroup(endpoint.Group), resolveKey, eventAction, message, endpoint.Name),
-		Headers: map[string]string{
-			"Content-Type": "application/json",
-		},
-	}
+}`, provider.getIntegrationKeyForGroup(endpoint.Group), resolveKey, eventAction, message, endpoint.Name)
 }
 
 // getIntegrationKeyForGroup returns the appropriate pagerduty integration key for a given group
@@ -94,3 +126,9 @@ func (provider *AlertProvider) getIntegrationKeyForGroup(group string) string {
 func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
 	return provider.DefaultAlert
 }
+
+type pagerDutyResponsePayload struct {
+	Status   string `json:"status"`
+	Message  string `json:"message"`
+	DedupKey string `json:"dedup_key"`
+}

alerting/provider/pagerduty/pagerduty_test.go

@@ -3,11 +3,12 @@ package pagerduty
 import (
 	"encoding/json"
 	"net/http"
-	"strings"
 	"testing"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -57,107 +58,118 @@ func TestAlertProvider_IsValidWithOverride(t *testing.T) {
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{IntegrationKey: "00000000000000000000000000000000"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
-	}
-	if !strings.Contains(customAlertProvider.Body, "RESOLVED") {
-		t.Error("customAlertProvider.Body should've contained the substring RESOLVED")
-	}
-	if customAlertProvider.URL != "https://events.pagerduty.com/v2/enqueue" {
-		t.Errorf("expected URL to be %s, got %s", "https://events.pagerduty.com/v2/enqueue", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
-	}
-}
-
-func TestAlertProvider_ToCustomAlertProviderWithResolvedAlertAndOverride(t *testing.T) {
-	provider := AlertProvider{
-		IntegrationKey: "",
-		Overrides: []Override{
-			{
-				IntegrationKey: "00000000000000000000000000000000",
-				Group:          "group",
-			},
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:     "triggered",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "triggered-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+		{
+			Name:     "resolved",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "resolved-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
 		},
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
-	}
-	if !strings.Contains(customAlertProvider.Body, "RESOLVED") {
-		t.Error("customAlertProvider.Body should've contained the substring RESOLVED")
-	}
-	if customAlertProvider.URL != "https://events.pagerduty.com/v2/enqueue" {
-		t.Errorf("expected URL to be %s, got %s", "https://events.pagerduty.com/v2/enqueue", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{IntegrationKey: "00000000000000000000000000000000"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
-	}
-	if !strings.Contains(customAlertProvider.Body, "TRIGGERED") {
-		t.Error("customAlertProvider.Body should've contained the substring TRIGGERED")
-	}
-	if customAlertProvider.URL != "https://events.pagerduty.com/v2/enqueue" {
-		t.Errorf("expected URL to be %s, got %s", "https://events.pagerduty.com/v2/enqueue", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
-	}
-}
-
-func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlertAndOverride(t *testing.T) {
-	provider := AlertProvider{
-		IntegrationKey: "",
-		Overrides: []Override{
-			{
-				IntegrationKey: "00000000000000000000000000000000",
-				Group:          "group",
-			},
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	description := "test"
+	scenarios := []struct {
+		Name         string
+		Provider     AlertProvider
+		Alert        alert.Alert
+		Resolved     bool
+		ExpectedBody string
+	}{
+		{
+			Name:         "triggered",
+			Provider:     AlertProvider{IntegrationKey: "00000000000000000000000000000000"},
+			Alert:        alert.Alert{Description: &description},
+			Resolved:     false,
+			ExpectedBody: "{\n  \"routing_key\": \"00000000000000000000000000000000\",\n  \"dedup_key\": \"\",\n  \"event_action\": \"trigger\",\n  \"payload\": {\n    \"summary\": \"TRIGGERED:  - test\",\n    \"source\": \"\",\n    \"severity\": \"critical\"\n  }\n}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{IntegrationKey: "00000000000000000000000000000000"},
+			Alert:        alert.Alert{Description: &description, ResolveKey: "key"},
+			Resolved:     true,
+			ExpectedBody: "{\n  \"routing_key\": \"00000000000000000000000000000000\",\n  \"dedup_key\": \"key\",\n  \"event_action\": \"resolve\",\n  \"payload\": {\n    \"summary\": \"RESOLVED:  - test\",\n    \"source\": \"\",\n    \"severity\": \"critical\"\n  }\n}",
 		},
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
-	}
-	if !strings.Contains(customAlertProvider.Body, "TRIGGERED") {
-		t.Error("customAlertProvider.Body should've contained the substring TRIGGERED")
-	}
-	if customAlertProvider.URL != "https://events.pagerduty.com/v2/enqueue" {
-		t.Errorf("expected URL to be %s, got %s", "https://events.pagerduty.com/v2/enqueue", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			body := scenario.Provider.buildRequestBody(&core.Endpoint{}, &scenario.Alert, &core.Result{}, scenario.Resolved)
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected %s, got %s", scenario.ExpectedBody, body)
+			}
+			out := make(map[string]interface{})
+			if err := json.Unmarshal([]byte(body), &out); err != nil {
+				t.Error("expected body to be valid JSON, got error:", err.Error())
+			}
+		})
 	}
 }
 
@@ -223,3 +235,12 @@ func TestAlertProvider_getIntegrationKeyForGroup(t *testing.T) {
 		})
 	}
 }
+
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
+	}
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
+	}
+}

alerting/provider/provider.go

@@ -4,6 +4,8 @@ import (
 	"github.com/TwiN/gatus/v3/alerting/alert"
 	"github.com/TwiN/gatus/v3/alerting/provider/custom"
 	"github.com/TwiN/gatus/v3/alerting/provider/discord"
+	"github.com/TwiN/gatus/v3/alerting/provider/email"
+	"github.com/TwiN/gatus/v3/alerting/provider/googlechat"
 	"github.com/TwiN/gatus/v3/alerting/provider/mattermost"
 	"github.com/TwiN/gatus/v3/alerting/provider/messagebird"
 	"github.com/TwiN/gatus/v3/alerting/provider/pagerduty"
@@ -19,11 +21,11 @@ type AlertProvider interface {
 	// IsValid returns whether the provider's configuration is valid
 	IsValid() bool
 
-	// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-	ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider
-
 	// GetDefaultAlert returns the provider's default alert configuration
 	GetDefaultAlert() *alert.Alert
+
+	// Send an alert using the provider
+	Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error
 }
 
 // ParseWithDefaultAlert parses an Endpoint alert by using the provider's default alert as a baseline
@@ -52,6 +54,8 @@ var (
 	// Validate interface implementation on compile
 	_ AlertProvider = (*custom.AlertProvider)(nil)
 	_ AlertProvider = (*discord.AlertProvider)(nil)
+	_ AlertProvider = (*email.AlertProvider)(nil)
+	_ AlertProvider = (*googlechat.AlertProvider)(nil)
 	_ AlertProvider = (*mattermost.AlertProvider)(nil)
 	_ AlertProvider = (*messagebird.AlertProvider)(nil)
 	_ AlertProvider = (*pagerduty.AlertProvider)(nil)

alerting/provider/slack/slack.go

@@ -1,11 +1,13 @@
 package slack
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"net/http"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/alerting/provider/custom"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
 )
 
@@ -14,7 +16,7 @@ type AlertProvider struct {
 	WebhookURL string `yaml:"webhook-url"` // Slack webhook URL
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
-	DefaultAlert *alert.Alert `yaml:"default-alert"`
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -22,14 +24,33 @@ func (provider *AlertProvider) IsValid() bool {
 	return len(provider.WebhookURL) > 0
 }
 
-// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
+// Send an alert using the provider
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
+	request, err := http.NewRequest(http.MethodPost, provider.WebhookURL, buffer)
+	if err != nil {
+		return err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	response, err := client.GetHTTPClient(nil).Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+	}
+	return err
+}
+
+// buildRequestBody builds the request body for the provider
+func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
 	var message, color, results string
 	if resolved {
-		message = fmt.Sprintf("An alert for *%s* has been resolved after passing successfully %d time(s) in a row", endpoint.Name, alert.SuccessThreshold)
+		message = fmt.Sprintf("An alert for *%s* has been resolved after passing successfully %d time(s) in a row", endpoint.DisplayName(), alert.SuccessThreshold)
 		color = "#36A64F"
 	} else {
-		message = fmt.Sprintf("An alert for *%s* has been triggered due to having failed %d time(s) in a row", endpoint.Name, alert.FailureThreshold)
+		message = fmt.Sprintf("An alert for *%s* has been triggered due to having failed %d time(s) in a row", endpoint.DisplayName(), alert.FailureThreshold)
 		color = "#DD0000"
 	}
 	for _, conditionResult := range result.ConditionResults {
@@ -45,10 +66,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
 	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
 		description = ":\\n> " + alertDescription
 	}
-	return &custom.AlertProvider{
-		URL:    provider.WebhookURL,
-		Method: http.MethodPost,
-		Body: fmt.Sprintf(`{
+	return fmt.Sprintf(`{
   "text": "",
   "attachments": [
     {
@@ -65,9 +83,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
       ]
     }
   ]
-}`, message, description, color, results),
-		Headers: map[string]string{"Content-Type": "application/json"},
-	}
+}`, message, description, color, results)
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/slack/slack_test.go

@@ -3,11 +3,12 @@ package slack
 import (
 	"encoding/json"
 	"net/http"
-	"strings"
 	"testing"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -15,56 +16,162 @@ func TestAlertProvider_IsValid(t *testing.T) {
 	if invalidProvider.IsValid() {
 		t.Error("provider shouldn't have been valid")
 	}
-	validProvider := AlertProvider{WebhookURL: "http://example.com"}
+	validProvider := AlertProvider{WebhookURL: "https://example.com"}
 	if !validProvider.IsValid() {
 		t.Error("provider should've been valid")
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.com"}
-	alertDescription := "test"
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{Name: "svc"}, &alert.Alert{Description: &alertDescription}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:     "triggered",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "triggered-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+		{
+			Name:     "resolved",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "resolved-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "resolved") {
-		t.Error("customAlertProvider.Body should've contained the substring resolved")
-	}
-	if customAlertProvider.URL != "http://example.com" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
-	}
-	if expected := "An alert for *svc* has been resolved after passing successfully 0 time(s) in a row:\n> test"; expected != body["attachments"].([]interface{})[0].(map[string]interface{})["text"] {
-		t.Errorf("expected $.attachments[0].description to be %s, got %s", expected, body["attachments"].([]interface{})[0].(map[string]interface{})["text"])
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.com"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name         string
+		Provider     AlertProvider
+		Endpoint     core.Endpoint
+		Alert        alert.Alert
+		Resolved     bool
+		ExpectedBody string
+	}{
+		{
+			Name:         "triggered",
+			Provider:     AlertProvider{},
+			Endpoint:     core.Endpoint{Name: "name"},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "{\n  \"text\": \"\",\n  \"attachments\": [\n    {\n      \"title\": \":helmet_with_white_cross: Gatus\",\n      \"text\": \"An alert for *name* has been triggered due to having failed 3 time(s) in a row:\\n> description-1\",\n      \"short\": false,\n      \"color\": \"#DD0000\",\n      \"fields\": [\n        {\n          \"title\": \"Condition results\",\n          \"value\": \":x: - `[CONNECTED] == true`\\n:x: - `[STATUS] == 200`\\n\",\n          \"short\": false\n        }\n      ]\n    }\n  ]\n}",
+		},
+		{
+			Name:         "triggered-with-group",
+			Provider:     AlertProvider{},
+			Endpoint:     core.Endpoint{Name: "name", Group: "group"},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "{\n  \"text\": \"\",\n  \"attachments\": [\n    {\n      \"title\": \":helmet_with_white_cross: Gatus\",\n      \"text\": \"An alert for *group/name* has been triggered due to having failed 3 time(s) in a row:\\n> description-1\",\n      \"short\": false,\n      \"color\": \"#DD0000\",\n      \"fields\": [\n        {\n          \"title\": \"Condition results\",\n          \"value\": \":x: - `[CONNECTED] == true`\\n:x: - `[STATUS] == 200`\\n\",\n          \"short\": false\n        }\n      ]\n    }\n  ]\n}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{},
+			Endpoint:     core.Endpoint{Name: "name"},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\n  \"text\": \"\",\n  \"attachments\": [\n    {\n      \"title\": \":helmet_with_white_cross: Gatus\",\n      \"text\": \"An alert for *name* has been resolved after passing successfully 5 time(s) in a row:\\n> description-2\",\n      \"short\": false,\n      \"color\": \"#36A64F\",\n      \"fields\": [\n        {\n          \"title\": \"Condition results\",\n          \"value\": \":white_check_mark: - `[CONNECTED] == true`\\n:white_check_mark: - `[STATUS] == 200`\\n\",\n          \"short\": false\n        }\n      ]\n    }\n  ]\n}",
+		},
+		{
+			Name:         "resolved-with-group",
+			Provider:     AlertProvider{},
+			Endpoint:     core.Endpoint{Name: "name", Group: "group"},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\n  \"text\": \"\",\n  \"attachments\": [\n    {\n      \"title\": \":helmet_with_white_cross: Gatus\",\n      \"text\": \"An alert for *group/name* has been resolved after passing successfully 5 time(s) in a row:\\n> description-2\",\n      \"short\": false,\n      \"color\": \"#36A64F\",\n      \"fields\": [\n        {\n          \"title\": \"Condition results\",\n          \"value\": \":white_check_mark: - `[CONNECTED] == true`\\n:white_check_mark: - `[STATUS] == 200`\\n\",\n          \"short\": false\n        }\n      ]\n    }\n  ]\n}",
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "triggered") {
-		t.Error("customAlertProvider.Body should've contained the substring triggered")
-	}
-	if customAlertProvider.URL != "http://example.com" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			body := scenario.Provider.buildRequestBody(
+				&scenario.Endpoint,
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected %s, got %s", scenario.ExpectedBody, body)
+			}
+			out := make(map[string]interface{})
+			if err := json.Unmarshal([]byte(body), &out); err != nil {
+				t.Error("expected body to be valid JSON, got error:", err.Error())
+			}
+		})
+	}
+}
+
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
+	}
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
 	}
 }

alerting/provider/teams/teams.go

@@ -1,11 +1,13 @@
 package teams
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"net/http"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/alerting/provider/custom"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
 )
 
@@ -14,7 +16,7 @@ type AlertProvider struct {
 	WebhookURL string `yaml:"webhook-url"`
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
-	DefaultAlert *alert.Alert `yaml:"default-alert"`
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -22,15 +24,33 @@ func (provider *AlertProvider) IsValid() bool {
 	return len(provider.WebhookURL) > 0
 }
 
-// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
-	var message string
-	var color string
+// Send an alert using the provider
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
+	request, err := http.NewRequest(http.MethodPost, provider.WebhookURL, buffer)
+	if err != nil {
+		return err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	response, err := client.GetHTTPClient(nil).Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+	}
+	return err
+}
+
+// buildRequestBody builds the request body for the provider
+func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
+	var message, color string
 	if resolved {
-		message = fmt.Sprintf("An alert for *%s* has been resolved after passing successfully %d time(s) in a row", endpoint.Name, alert.SuccessThreshold)
+		message = fmt.Sprintf("An alert for *%s* has been resolved after passing successfully %d time(s) in a row", endpoint.DisplayName(), alert.SuccessThreshold)
 		color = "#36A64F"
 	} else {
-		message = fmt.Sprintf("An alert for *%s* has been triggered due to having failed %d time(s) in a row", endpoint.Name, alert.FailureThreshold)
+		message = fmt.Sprintf("An alert for *%s* has been triggered due to having failed %d time(s) in a row", endpoint.DisplayName(), alert.FailureThreshold)
 		color = "#DD0000"
 	}
 	var results string
@@ -47,10 +67,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
 	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
 		description = ":\\n> " + alertDescription
 	}
-	return &custom.AlertProvider{
-		URL:    provider.WebhookURL,
-		Method: http.MethodPost,
-		Body: fmt.Sprintf(`{
+	return fmt.Sprintf(`{
   "@type": "MessageCard",
   "@context": "http://schema.org/extensions",
   "themeColor": "%s",
@@ -66,9 +83,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
       "text": "%s"
     }
   ]
-}`, color, message, description, endpoint.URL, results),
-		Headers: map[string]string{"Content-Type": "application/json"},
-	}
+}`, color, message, description, endpoint.URL, results)
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/teams/teams_test.go

@@ -3,11 +3,12 @@ package teams
 import (
 	"encoding/json"
 	"net/http"
-	"strings"
 	"testing"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -21,50 +22,137 @@ func TestAlertProvider_IsValid(t *testing.T) {
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.org"}
-	alertDescription := "test"
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{Name: "svc"}, &alert.Alert{Description: &alertDescription}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:     "triggered",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "triggered-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+		{
+			Name:     "resolved",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "resolved-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "resolved") {
-		t.Error("customAlertProvider.Body should've contained the substring resolved")
-	}
-	if customAlertProvider.URL != "http://example.org" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
-	}
-	if expected := "An alert for *svc* has been resolved after passing successfully 0 time(s) in a row:\n> test"; expected != body["text"] {
-		t.Errorf("expected $.text to be %s, got %s", expected, body["text"])
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.org"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name         string
+		Provider     AlertProvider
+		Alert        alert.Alert
+		Resolved     bool
+		ExpectedBody string
+	}{
+		{
+			Name:         "triggered",
+			Provider:     AlertProvider{},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "{\n  \"@type\": \"MessageCard\",\n  \"@context\": \"http://schema.org/extensions\",\n  \"themeColor\": \"#DD0000\",\n  \"title\": \"&#x1F6A8; Gatus\",\n  \"text\": \"An alert for *endpoint-name* has been triggered due to having failed 3 time(s) in a row:\\n> description-1\",\n  \"sections\": [\n    {\n      \"activityTitle\": \"URL\",\n      \"text\": \"\"\n    },\n    {\n      \"activityTitle\": \"Condition results\",\n      \"text\": \"&#x274C; - `[CONNECTED] == true`<br/>&#x274C; - `[STATUS] == 200`<br/>\"\n    }\n  ]\n}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\n  \"@type\": \"MessageCard\",\n  \"@context\": \"http://schema.org/extensions\",\n  \"themeColor\": \"#36A64F\",\n  \"title\": \"&#x1F6A8; Gatus\",\n  \"text\": \"An alert for *endpoint-name* has been resolved after passing successfully 5 time(s) in a row:\\n> description-2\",\n  \"sections\": [\n    {\n      \"activityTitle\": \"URL\",\n      \"text\": \"\"\n    },\n    {\n      \"activityTitle\": \"Condition results\",\n      \"text\": \"&#x2705; - `[CONNECTED] == true`<br/>&#x2705; - `[STATUS] == 200`<br/>\"\n    }\n  ]\n}",
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "triggered") {
-		t.Error("customAlertProvider.Body should've contained the substring triggered")
-	}
-	if customAlertProvider.URL != "http://example.org" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			body := scenario.Provider.buildRequestBody(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected %s, got %s", scenario.ExpectedBody, body)
+			}
+			out := make(map[string]interface{})
+			if err := json.Unmarshal([]byte(body), &out); err != nil {
+				t.Error("expected body to be valid JSON, got error:", err.Error())
+			}
+		})
+	}
+}
+
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
+	}
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
 	}
 }

alerting/provider/telegram/telegram.go

@@ -1,21 +1,26 @@
 package telegram
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"net/http"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/alerting/provider/custom"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
 )
 
+const defaultAPIURL = "https://api.telegram.org"
+
 // AlertProvider is the configuration necessary for sending an alert using Telegram
 type AlertProvider struct {
-	Token string `yaml:"token"`
-	ID    string `yaml:"id"`
+	Token  string `yaml:"token"`
+	ID     string `yaml:"id"`
+	APIURL string `yaml:"api-url"`
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
-	DefaultAlert *alert.Alert `yaml:"default-alert"`
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -23,13 +28,36 @@ func (provider *AlertProvider) IsValid() bool {
 	return len(provider.Token) > 0 && len(provider.ID) > 0
 }
 
-// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
+// Send an alert using the provider
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
+	apiURL := provider.APIURL
+	if apiURL == "" {
+		apiURL = defaultAPIURL
+	}
+	request, err := http.NewRequest(http.MethodPost, fmt.Sprintf("%s/bot%s/sendMessage", apiURL, provider.Token), buffer)
+	if err != nil {
+		return err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	response, err := client.GetHTTPClient(nil).Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+	}
+	return err
+}
+
+// buildRequestBody builds the request body for the provider
+func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
 	var message, results string
 	if resolved {
-		message = fmt.Sprintf("An alert for *%s* has been resolved:\\n—\\n    _healthcheck passing successfully %d time(s) in a row_\\n—  ", endpoint.Name, alert.FailureThreshold)
+		message = fmt.Sprintf("An alert for *%s* has been resolved:\\n—\\n    _healthcheck passing successfully %d time(s) in a row_\\n—  ", endpoint.DisplayName(), alert.FailureThreshold)
 	} else {
-		message = fmt.Sprintf("An alert for *%s* has been triggered:\\n—\\n    _healthcheck failed %d time(s) in a row_\\n—  ", endpoint.Name, alert.FailureThreshold)
+		message = fmt.Sprintf("An alert for *%s* has been triggered:\\n—\\n    _healthcheck failed %d time(s) in a row_\\n—  ", endpoint.DisplayName(), alert.FailureThreshold)
 	}
 	for _, conditionResult := range result.ConditionResults {
 		var prefix string
@@ -46,12 +74,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
 	} else {
 		text = fmt.Sprintf("⛑ *Gatus* \\n%s \\n*Condition results*\\n%s", message, results)
 	}
-	return &custom.AlertProvider{
-		URL:     fmt.Sprintf("https://api.telegram.org/bot%s/sendMessage", provider.Token),
-		Method:  http.MethodPost,
-		Body:    fmt.Sprintf(`{"chat_id": "%s", "text": "%s", "parse_mode": "MARKDOWN"}`, provider.ID, text),
-		Headers: map[string]string{"Content-Type": "application/json"},
-	}
+	return fmt.Sprintf(`{"chat_id": "%s", "text": "%s", "parse_mode": "MARKDOWN"}`, provider.ID, text)
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/telegram/telegram_test.go

@@ -2,13 +2,13 @@ package telegram
 
 import (
 	"encoding/json"
-	"fmt"
 	"net/http"
-	"strings"
 	"testing"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v3/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -22,70 +22,137 @@ func TestAlertProvider_IsValid(t *testing.T) {
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{Token: "123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11", ID: "12345678"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_Send(t *testing.T) {
+	defer client.InjectHTTPClient(nil)
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name             string
+		Provider         AlertProvider
+		Alert            alert.Alert
+		Resolved         bool
+		MockRoundTripper test.MockRoundTripper
+		ExpectedError    bool
+	}{
+		{
+			Name:     "triggered",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "triggered-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: false,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
+		{
+			Name:     "resolved",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}
+			}),
+			ExpectedError: false,
+		},
+		{
+			Name:     "resolved-error",
+			Provider: AlertProvider{},
+			Alert:    alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved: true,
+			MockRoundTripper: test.MockRoundTripper(func(r *http.Request) *http.Response {
+				return &http.Response{StatusCode: http.StatusInternalServerError, Body: http.NoBody}
+			}),
+			ExpectedError: true,
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "resolved") {
-		t.Error("customAlertProvider.Body should've contained the substring resolved")
-	}
-	if customAlertProvider.URL != fmt.Sprintf("https://api.telegram.org/bot%s/sendMessage", provider.Token) {
-		t.Errorf("expected URL to be %s, got %s", fmt.Sprintf("https://api.telegram.org/bot%s/sendMessage", provider.Token), customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	//_, err := json.Marshal(customAlertProvider.Body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			client.InjectHTTPClient(&http.Client{Transport: scenario.MockRoundTripper})
+			err := scenario.Provider.Send(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if scenario.ExpectedError && err == nil {
+				t.Error("expected error, got none")
+			}
+			if !scenario.ExpectedError && err != nil {
+				t.Error("expected no error, got", err.Error())
+			}
+		})
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{Token: "123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11", ID: "0123456789"}
-	description := "Healthcheck Successful"
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{Description: &description}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name         string
+		Provider     AlertProvider
+		Alert        alert.Alert
+		Resolved     bool
+		ExpectedBody string
+	}{
+		{
+			Name:         "triggered",
+			Provider:     AlertProvider{ID: "123"},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "{\"chat_id\": \"123\", \"text\": \"⛑ *Gatus* \\nAn alert for *endpoint-name* has been triggered:\\n—\\n    _healthcheck failed 3 time(s) in a row_\\n—   \\n*Description* \\n_description-1_  \\n\\n*Condition results*\\n❌ - `[CONNECTED] == true`\\n❌ - `[STATUS] == 200`\\n\", \"parse_mode\": \"MARKDOWN\"}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{ID: "123"},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\"chat_id\": \"123\", \"text\": \"⛑ *Gatus* \\nAn alert for *endpoint-name* has been resolved:\\n—\\n    _healthcheck passing successfully 3 time(s) in a row_\\n—   \\n*Description* \\n_description-2_  \\n\\n*Condition results*\\n✅ - `[CONNECTED] == true`\\n✅ - `[STATUS] == 200`\\n\", \"parse_mode\": \"MARKDOWN\"}",
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "triggered") {
-		t.Error("customAlertProvider.Body should've contained the substring triggered")
-	}
-	if customAlertProvider.URL != fmt.Sprintf("https://api.telegram.org/bot%s/sendMessage", provider.Token) {
-		t.Errorf("expected URL to be %s, got %s", fmt.Sprintf("https://api.telegram.org/bot%s/sendMessage", provider.Token), customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			body := scenario.Provider.buildRequestBody(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected %s, got %s", scenario.ExpectedBody, body)
+			}
+			out := make(map[string]interface{})
+			if err := json.Unmarshal([]byte(body), &out); err != nil {
+				t.Error("expected body to be valid JSON, got error:", err.Error())
+			}
+		})
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithDescription(t *testing.T) {
-	provider := AlertProvider{Token: "123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11", ID: "0123456789"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{}, &alert.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
 	}
-	if !strings.Contains(customAlertProvider.Body, "triggered") {
-		t.Error("customAlertProvider.Body should've contained the substring triggered")
-	}
-	if customAlertProvider.URL != fmt.Sprintf("https://api.telegram.org/bot%s/sendMessage", provider.Token) {
-		t.Errorf("expected URL to be %s, got %s", fmt.Sprintf("https://api.telegram.org/bot%s/sendMessage", provider.Token), customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	body := make(map[string]interface{})
-	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
-	if err != nil {
-		t.Error("expected body to be valid JSON, got error:", err.Error())
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
 	}
 }

alerting/provider/twilio/twilio.go

@@ -1,13 +1,15 @@
 package twilio
 
 import (
+	"bytes"
 	"encoding/base64"
 	"fmt"
+	"io"
 	"net/http"
 	"net/url"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/alerting/provider/custom"
+	"github.com/TwiN/gatus/v3/client"
 	"github.com/TwiN/gatus/v3/core"
 )
 
@@ -19,7 +21,7 @@ type AlertProvider struct {
 	To    string `yaml:"to"`
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
-	DefaultAlert *alert.Alert `yaml:"default-alert"`
+	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -27,27 +29,39 @@ func (provider *AlertProvider) IsValid() bool {
 	return len(provider.Token) > 0 && len(provider.SID) > 0 && len(provider.From) > 0 && len(provider.To) > 0
 }
 
-// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, alert *alert.Alert, _ *core.Result, resolved bool) *custom.AlertProvider {
+// Send an alert using the provider
+func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
+	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
+	request, err := http.NewRequest(http.MethodPost, fmt.Sprintf("https://api.twilio.com/2010-04-01/Accounts/%s/Messages.json", provider.SID), buffer)
+	if err != nil {
+		return err
+	}
+	request.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	request.Header.Set("Authorization", fmt.Sprintf("Basic %s", base64.StdEncoding.EncodeToString([]byte(provider.SID+":"+provider.Token))))
+	response, err := client.GetHTTPClient(nil).Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		body, _ := io.ReadAll(response.Body)
+		return fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+	}
+	return err
+}
+
+// buildRequestBody builds the request body for the provider
+func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
 	var message string
 	if resolved {
-		message = fmt.Sprintf("RESOLVED: %s - %s", endpoint.Name, alert.GetDescription())
+		message = fmt.Sprintf("RESOLVED: %s - %s", endpoint.DisplayName(), alert.GetDescription())
 	} else {
-		message = fmt.Sprintf("TRIGGERED: %s - %s", endpoint.Name, alert.GetDescription())
-	}
-	return &custom.AlertProvider{
-		URL:    fmt.Sprintf("https://api.twilio.com/2010-04-01/Accounts/%s/Messages.json", provider.SID),
-		Method: http.MethodPost,
-		Body: url.Values{
-			"To":   {provider.To},
-			"From": {provider.From},
-			"Body": {message},
-		}.Encode(),
-		Headers: map[string]string{
-			"Content-Type":  "application/x-www-form-urlencoded",
-			"Authorization": fmt.Sprintf("Basic %s", base64.StdEncoding.EncodeToString([]byte(fmt.Sprintf("%s:%s", provider.SID, provider.Token)))),
-		},
+		message = fmt.Sprintf("TRIGGERED: %s - %s", endpoint.DisplayName(), alert.GetDescription())
 	}
+	return url.Values{
+		"To":   {provider.To},
+		"From": {provider.From},
+		"Body": {message},
+	}.Encode()
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/twilio/twilio_test.go

@@ -1,8 +1,6 @@
 package twilio
 
 import (
-	"net/http"
-	"strings"
 	"testing"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
@@ -25,54 +23,56 @@ func TestTwilioAlertProvider_IsValid(t *testing.T) {
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{
-		SID:   "1",
-		Token: "2",
-		From:  "3",
-		To:    "4",
+func TestAlertProvider_buildRequestBody(t *testing.T) {
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []struct {
+		Name         string
+		Provider     AlertProvider
+		Alert        alert.Alert
+		Resolved     bool
+		ExpectedBody string
+	}{
+		{
+			Name:         "triggered",
+			Provider:     AlertProvider{SID: "1", Token: "2", From: "3", To: "4"},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "Body=TRIGGERED%3A+endpoint-name+-+description-1&From=3&To=4",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{SID: "1", Token: "2", From: "3", To: "4"},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "Body=RESOLVED%3A+endpoint-name+-+description-2&From=3&To=4",
+		},
 	}
-	description := "alert-description"
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{Name: "endpoint-name"}, &alert.Alert{Description: &description}, &core.Result{}, true)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
-	}
-	if !strings.Contains(customAlertProvider.Body, "RESOLVED") {
-		t.Error("customAlertProvider.Body should've contained the substring RESOLVED")
-	}
-	if customAlertProvider.URL != "https://api.twilio.com/2010-04-01/Accounts/1/Messages.json" {
-		t.Errorf("expected URL to be %s, got %s", "https://api.twilio.com/2010-04-01/Accounts/1/Messages.json", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	if customAlertProvider.Body != "Body=RESOLVED%3A+endpoint-name+-+alert-description&From=3&To=4" {
-		t.Errorf("expected body to be %s, got %s", "Body=RESOLVED%3A+endpoint-name+-+alert-description&From=3&To=4", customAlertProvider.Body)
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			body := scenario.Provider.buildRequestBody(
+				&core.Endpoint{Name: "endpoint-name"},
+				&scenario.Alert,
+				&core.Result{
+					ConditionResults: []*core.ConditionResult{
+						{Condition: "[CONNECTED] == true", Success: scenario.Resolved},
+						{Condition: "[STATUS] == 200", Success: scenario.Resolved},
+					},
+				},
+				scenario.Resolved,
+			)
+			if body != scenario.ExpectedBody {
+				t.Errorf("expected %s, got %s", scenario.ExpectedBody, body)
+			}
+		})
 	}
 }
 
-func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{
-		SID:   "4",
-		Token: "3",
-		From:  "2",
-		To:    "1",
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
 	}
-	description := "alert-description"
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Endpoint{Name: "endpoint-name"}, &alert.Alert{Description: &description}, &core.Result{}, false)
-	if customAlertProvider == nil {
-		t.Fatal("customAlertProvider shouldn't have been nil")
-	}
-	if !strings.Contains(customAlertProvider.Body, "TRIGGERED") {
-		t.Error("customAlertProvider.Body should've contained the substring TRIGGERED")
-	}
-	if customAlertProvider.URL != "https://api.twilio.com/2010-04-01/Accounts/4/Messages.json" {
-		t.Errorf("expected URL to be %s, got %s", "https://api.twilio.com/2010-04-01/Accounts/4/Messages.json", customAlertProvider.URL)
-	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
-	}
-	if customAlertProvider.Body != "Body=TRIGGERED%3A+endpoint-name+-+alert-description&From=2&To=1" {
-		t.Errorf("expected body to be %s, got %s", "Body=TRIGGERED%3A+endpoint-name+-+alert-description&From=2&To=1", customAlertProvider.Body)
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
 	}
 }

client/client.go

@@ -14,8 +14,14 @@ import (
 	"github.com/go-ping/ping"
 )
 
+// injectedHTTPClient is used for testing purposes
+var injectedHTTPClient *http.Client
+
 // GetHTTPClient returns the shared HTTP client
 func GetHTTPClient(config *Config) *http.Client {
+	if injectedHTTPClient != nil {
+		return injectedHTTPClient
+	}
 	if config == nil {
 		return defaultConfig.getHTTPClient()
 	}
@@ -104,3 +110,8 @@ func Ping(address string, config *Config) (bool, time.Duration) {
 	}
 	return true, 0
 }
+
+// InjectHTTPClient is used to inject a custom HTTP client for testing purposes
+func InjectHTTPClient(httpClient *http.Client) {
+	injectedHTTPClient = httpClient
+}

client/client_test.go

@@ -1,8 +1,13 @@
 package client
 
 import (
+	"bytes"
+	"io/ioutil"
+	"net/http"
 	"testing"
 	"time"
+
+	"github.com/TwiN/gatus/v3/test"
 )
 
 func TestGetHTTPClient(t *testing.T) {
@@ -10,6 +15,12 @@ func TestGetHTTPClient(t *testing.T) {
 		Insecure:       false,
 		IgnoreRedirect: false,
 		Timeout:        0,
+		OAuth2Config: &OAuth2Config{
+			ClientID:     "00000000-0000-0000-0000-000000000000",
+			ClientSecret: "secretsauce",
+			TokenURL:     "https://token-server.local/token",
+			Scopes:       []string{"https://application.local/.default"},
+		},
 	}
 	cfg.ValidateAndSetDefaults()
 	if GetHTTPClient(cfg) == nil {
@@ -146,3 +157,71 @@ func TestCanCreateTCPConnection(t *testing.T) {
 		t.Error("should've failed, because there's no port in the address")
 	}
 }
+
+// This test checks if a HTTP client configured with `configureOAuth2()` automatically
+// performs a Client Credentials OAuth2 flow and adds the obtained token as a `Authorization`
+// header to all outgoing HTTP calls.
+func TestHttpClientProvidesOAuth2BearerToken(t *testing.T) {
+
+	defer InjectHTTPClient(nil)
+
+	oAuth2Config := &OAuth2Config{
+		ClientID:     "00000000-0000-0000-0000-000000000000",
+		ClientSecret: "secretsauce",
+		TokenURL:     "https://token-server.local/token",
+		Scopes:       []string{"https://application.local/.default"},
+	}
+
+	mockHttpClient := &http.Client{
+		Transport: test.MockRoundTripper(func(r *http.Request) *http.Response {
+
+			// if the mock HTTP client tries to get a token from the `token-server`
+			// we provide the expected token response
+			if r.Host == "token-server.local" {
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Body: ioutil.NopCloser(bytes.NewReader(
+						[]byte(
+							`{"token_type":"Bearer","expires_in":3599,"ext_expires_in":3599,"access_token":"secret-token"}`,
+						),
+					)),
+				}
+			}
+
+			// to verify the headers were sent as expected, we echo them back in the
+			// `X-Org-Authorization` header and check if the token value matches our
+			// mocked `token-server` response
+			return &http.Response{
+				StatusCode: http.StatusOK,
+				Header: map[string][]string{
+					"X-Org-Authorization": {r.Header.Get("Authorization")},
+				},
+				Body: http.NoBody,
+			}
+		}),
+	}
+
+	mockHttpClientWithOAuth := configureOAuth2(mockHttpClient, *oAuth2Config)
+	InjectHTTPClient(mockHttpClientWithOAuth)
+
+	request, err := http.NewRequest(http.MethodPost, "http://127.0.0.1:8282", http.NoBody)
+	if err != nil {
+		t.Error("expected no error, got", err.Error())
+	}
+
+	response, err := mockHttpClientWithOAuth.Do(request)
+	if err != nil {
+		t.Error("expected no error, got", err.Error())
+	}
+
+	if response.Header == nil {
+		t.Error("expected response headers, but got nil")
+	}
+
+	// the mock response echos the Authorization header used in the request back
+	// to us as `X-Org-Authorization` header, we check here if the value matches
+	// our expected token `secret-token`
+	if response.Header.Get("X-Org-Authorization") != "Bearer secret-token" {
+		t.Error("exptected `secret-token` as Bearer token in the mocked response header `X-Org-Authorization`, but got", response.Header.Get("X-Org-Authorization"))
+	}
+}

client/config.go

@@ -1,9 +1,14 @@
 package client
 
 import (
+	"context"
 	"crypto/tls"
+	"errors"
 	"net/http"
 	"time"
+
+	"golang.org/x/oauth2"
+	"golang.org/x/oauth2/clientcredentials"
 )
 
 const (
@@ -11,7 +16,8 @@ const (
 )
 
 var (
-	// DefaultConfig is the default client configuration
+	ErrInvalidClientOAuth2Config = errors.New("invalid OAuth2 configuration, all fields are required")
+
 	defaultConfig = Config{
 		Insecure:       false,
 		IgnoreRedirect: false,
@@ -28,22 +34,50 @@ func GetDefaultConfig() *Config {
 // Config is the configuration for clients
 type Config struct {
 	// Insecure determines whether to skip verifying the server's certificate chain and host name
-	Insecure bool `yaml:"insecure"`
+	Insecure bool `yaml:"insecure,omitempty"`
 
 	// IgnoreRedirect determines whether to ignore redirects (true) or follow them (false, default)
-	IgnoreRedirect bool `yaml:"ignore-redirect"`
+	IgnoreRedirect bool `yaml:"ignore-redirect,omitempty"`
 
 	// Timeout for the client
 	Timeout time.Duration `yaml:"timeout"`
 
+	// OAuth2Config is the OAuth2 configuration used for the client.
+	//
+	// If non-nil, the http.Client returned by getHTTPClient will automatically retrieve a token if necessary.
+	// See configureOAuth2 for more details.
+	OAuth2Config *OAuth2Config `yaml:"oauth2,omitempty"`
+
 	httpClient *http.Client
 }
 
+// OAuth2Config is the configuration for the OAuth2 client credentials flow
+type OAuth2Config struct {
+	TokenURL     string   `yaml:"token-url"` // e.g. https://dev-12345678.okta.com/token
+	ClientID     string   `yaml:"client-id"`
+	ClientSecret string   `yaml:"client-secret"`
+	Scopes       []string `yaml:"scopes"` // e.g. ["openid"]
+}
+
 // ValidateAndSetDefaults validates the client configuration and sets the default values if necessary
-func (c *Config) ValidateAndSetDefaults() {
+func (c *Config) ValidateAndSetDefaults() error {
 	if c.Timeout < time.Millisecond {
 		c.Timeout = 10 * time.Second
 	}
+	if c.HasOAuth2Config() && !c.OAuth2Config.isValid() {
+		return ErrInvalidClientOAuth2Config
+	}
+	return nil
+}
+
+// HasOAuth2Config returns true if the client has OAuth2 configuration parameters
+func (c *Config) HasOAuth2Config() bool {
+	return c.OAuth2Config != nil
+}
+
+// isValid() returns true if the OAuth2 configuration is valid
+func (c *OAuth2Config) isValid() bool {
+	return len(c.TokenURL) > 0 && len(c.ClientID) > 0 && len(c.ClientSecret) > 0 && len(c.Scopes) > 0
 }
 
 // GetHTTPClient return an HTTP client matching the Config's parameters.
@@ -68,6 +102,22 @@ func (c *Config) getHTTPClient() *http.Client {
 				return nil
 			},
 		}
+		if c.HasOAuth2Config() {
+			c.httpClient = configureOAuth2(c.httpClient, *c.OAuth2Config)
+		}
 	}
 	return c.httpClient
 }
+
+// configureOAuth2 returns an HTTP client that will obtain and refresh tokens as necessary.
+// The returned Client and its Transport should not be modified.
+func configureOAuth2(httpClient *http.Client, c OAuth2Config) *http.Client {
+	oauth2cfg := clientcredentials.Config{
+		ClientID:     c.ClientID,
+		ClientSecret: c.ClientSecret,
+		Scopes:       c.Scopes,
+		TokenURL:     c.TokenURL,
+	}
+	ctx := context.WithValue(context.Background(), oauth2.HTTPClient, httpClient)
+	return oauth2cfg.Client(ctx)
+}

config/config.go

@@ -2,7 +2,6 @@ package config
 
 import (
 	"errors"
-	"io/ioutil"
 	"log"
 	"os"
 	"time"
@@ -142,7 +141,7 @@ func LoadDefaultConfiguration() (*Config, error) {
 
 func readConfigurationFile(fileName string) (config *Config, err error) {
 	var bytes []byte
-	if bytes, err = ioutil.ReadFile(fileName); err == nil {
+	if bytes, err = os.ReadFile(fileName); err == nil {
 		// file exists, so we'll parse it and return it
 		return parseAndValidateConfigBytes(bytes)
 	}
@@ -274,8 +273,10 @@ func validateAlertingConfig(alertingConfig *alerting.Config, endpoints []*core.E
 	alertTypes := []alert.Type{
 		alert.TypeCustom,
 		alert.TypeDiscord,
+		alert.TypeEmail,
 		alert.TypeMattermost,
 		alert.TypeMessagebird,
+		alert.TypeOpsgenie,
 		alert.TypePagerDuty,
 		alert.TypeSlack,
 		alert.TypeTeams,

config/config_test.go

@@ -1172,12 +1172,12 @@ endpoints:
 
 func TestParseAndValidateConfigBytesWithValidSecurityConfig(t *testing.T) {
 	const expectedUsername = "admin"
-	const expectedPasswordHash = "6b97ed68d14eb3f1aa959ce5d49c7dc612e1eb1dafd73b1e705847483fd6a6c809f2ceb4e8df6ff9984c6298ff0285cace6614bf8daa9f0070101b6c89899e22"
+	const expectedPasswordHash = "JDJhJDEwJHRiMnRFakxWazZLdXBzRERQazB1TE8vckRLY05Yb1hSdnoxWU0yQ1FaYXZRSW1McmladDYu"
 	config, err := parseAndValidateConfigBytes([]byte(fmt.Sprintf(`debug: true
 security:
   basic:
     username: "%s"
-    password-sha512: "%s"
+    password-bcrypt-base64: "%s"
 endpoints:
   - name: website
     url: https://twin.sh/health
@@ -1202,8 +1202,8 @@ endpoints:
 	if config.Security.Basic.Username != expectedUsername {
 		t.Errorf("config.Security.Basic.Username should've been %s, but was %s", expectedUsername, config.Security.Basic.Username)
 	}
-	if config.Security.Basic.PasswordSha512Hash != expectedPasswordHash {
-		t.Errorf("config.Security.Basic.PasswordSha512Hash should've been %s, but was %s", expectedPasswordHash, config.Security.Basic.PasswordSha512Hash)
+	if config.Security.Basic.PasswordBcryptHashBase64Encoded != expectedPasswordHash {
+		t.Errorf("config.Security.Basic.PasswordBcryptHashBase64Encoded should've been %s, but was %s", expectedPasswordHash, config.Security.Basic.PasswordSha512Hash)
 	}
 }
 

config/maintenance/maintenance.go

@@ -39,7 +39,6 @@ type Config struct {
 	Every []string `yaml:"every"`
 
 	durationToStartFromMidnight time.Duration
-	timeLocation                *time.Location
 }
 
 func GetDefaultConfig() *Config {

config/ui/ui.go

@@ -6,8 +6,10 @@ import (
 )
 
 const (
-	defaultTitle = "Health Dashboard | Gatus"
-	defaultLogo  = ""
+	defaultTitle  = "Health Dashboard | Gatus"
+	defaultHeader = "Health Status"
+	defaultLogo   = ""
+	defaultLink   = ""
 )
 
 var (
@@ -18,15 +20,19 @@ var (
 
 // Config is the configuration for the UI of Gatus
 type Config struct {
-	Title string `yaml:"title"` // Title of the page
-	Logo  string `yaml:"logo"`  // Logo to display on the page
+	Title  string `yaml:"title,omitempty"`  // Title of the page
+	Header string `yaml:"header,omitempty"` // Header is the text at the top of the page
+	Logo   string `yaml:"logo,omitempty"`   // Logo to display on the page
+	Link   string `yaml:"link,omitempty"`   // Link to open when clicking on the logo
 }
 
 // GetDefaultConfig returns a Config struct with the default values
 func GetDefaultConfig() *Config {
 	return &Config{
-		Title: defaultTitle,
-		Logo:  defaultLogo,
+		Title:  defaultTitle,
+		Header: defaultHeader,
+		Logo:   defaultLogo,
+		Link:   defaultLink,
 	}
 }
 
@@ -35,6 +41,12 @@ func (cfg *Config) ValidateAndSetDefaults() error {
 	if len(cfg.Title) == 0 {
 		cfg.Title = defaultTitle
 	}
+	if len(cfg.Header) == 0 {
+		cfg.Header = defaultHeader
+	}
+	if len(cfg.Header) == 0 {
+		cfg.Header = defaultLink
+	}
 	t, err := template.ParseFiles(StaticFolder + "/index.html")
 	if err != nil {
 		return err

config/ui/ui_test.go

@@ -9,10 +9,21 @@ func TestConfig_ValidateAndSetDefaults(t *testing.T) {
 	defer func() {
 		StaticFolder = "./web/static"
 	}()
-	cfg := &Config{Title: ""}
+	cfg := &Config{
+		Title:  "",
+		Header: "",
+		Logo:   "",
+		Link:   "",
+	}
 	if err := cfg.ValidateAndSetDefaults(); err != nil {
 		t.Error("expected no error, got", err.Error())
 	}
+	if cfg.Title != defaultTitle {
+		t.Errorf("expected title to be %s, got %s", defaultTitle, cfg.Title)
+	}
+	if cfg.Header != defaultHeader {
+		t.Errorf("expected header to be %s, got %s", defaultHeader, cfg.Header)
+	}
 }
 
 func TestGetDefaultConfig(t *testing.T) {

controller/controller_test.go

@@ -34,7 +34,7 @@ func TestHandle(t *testing.T) {
 	defer os.Clearenv()
 	Handle(cfg.Security, cfg.Web, cfg.UI, cfg.Metrics)
 	defer Shutdown()
-	request, _ := http.NewRequest("GET", "/health", nil)
+	request, _ := http.NewRequest("GET", "/health", http.NoBody)
 	responseRecorder := httptest.NewRecorder()
 	server.Handler.ServeHTTP(responseRecorder, request)
 	if responseRecorder.Code != http.StatusOK {

controller/handler/badge.go

@@ -43,20 +43,18 @@ func UptimeBadge(writer http.ResponseWriter, request *http.Request) {
 	uptime, err := store.Get().GetUptimeByKey(key, from, time.Now())
 	if err != nil {
 		if err == common.ErrEndpointNotFound {
-			writer.WriteHeader(http.StatusNotFound)
+			http.Error(writer, err.Error(), http.StatusNotFound)
 		} else if err == common.ErrInvalidTimeRange {
-			writer.WriteHeader(http.StatusBadRequest)
+			http.Error(writer, err.Error(), http.StatusBadRequest)
 		} else {
-			writer.WriteHeader(http.StatusInternalServerError)
+			http.Error(writer, err.Error(), http.StatusInternalServerError)
 		}
-		_, _ = writer.Write([]byte(err.Error()))
 		return
 	}
-	formattedDate := time.Now().Format(http.TimeFormat)
-	writer.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
-	writer.Header().Set("Date", formattedDate)
-	writer.Header().Set("Expires", formattedDate)
 	writer.Header().Set("Content-Type", "image/svg+xml")
+	writer.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
+	writer.Header().Set("Expires", "0")
+	writer.WriteHeader(http.StatusOK)
 	_, _ = writer.Write(generateUptimeBadgeSVG(duration, uptime))
 }
 
@@ -82,20 +80,18 @@ func ResponseTimeBadge(writer http.ResponseWriter, request *http.Request) {
 	averageResponseTime, err := store.Get().GetAverageResponseTimeByKey(key, from, time.Now())
 	if err != nil {
 		if err == common.ErrEndpointNotFound {
-			writer.WriteHeader(http.StatusNotFound)
+			http.Error(writer, err.Error(), http.StatusNotFound)
 		} else if err == common.ErrInvalidTimeRange {
-			writer.WriteHeader(http.StatusBadRequest)
+			http.Error(writer, err.Error(), http.StatusBadRequest)
 		} else {
-			writer.WriteHeader(http.StatusInternalServerError)
+			http.Error(writer, err.Error(), http.StatusInternalServerError)
 		}
-		_, _ = writer.Write([]byte(err.Error()))
 		return
 	}
-	formattedDate := time.Now().Format(http.TimeFormat)
-	writer.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
-	writer.Header().Set("Date", formattedDate)
-	writer.Header().Set("Expires", formattedDate)
 	writer.Header().Set("Content-Type", "image/svg+xml")
+	writer.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
+	writer.Header().Set("Expires", "0")
+	writer.WriteHeader(http.StatusOK)
 	_, _ = writer.Write(generateResponseTimeBadgeSVG(duration, averageResponseTime))
 }
 

controller/handler/badge_test.go

@@ -107,7 +107,7 @@ func TestUptimeBadge(t *testing.T) {
 	}
 	for _, scenario := range scenarios {
 		t.Run(scenario.Name, func(t *testing.T) {
-			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			request, _ := http.NewRequest("GET", scenario.Path, http.NoBody)
 			if scenario.Gzip {
 				request.Header.Set("Accept-Encoding", "gzip")
 			}

controller/handler/chart.go

@@ -45,18 +45,16 @@ func ResponseTimeChart(writer http.ResponseWriter, r *http.Request) {
 	hourlyAverageResponseTime, err := store.Get().GetHourlyAverageResponseTimeByKey(vars["key"], from, time.Now())
 	if err != nil {
 		if err == common.ErrEndpointNotFound {
-			writer.WriteHeader(http.StatusNotFound)
+			http.Error(writer, err.Error(), http.StatusNotFound)
 		} else if err == common.ErrInvalidTimeRange {
-			writer.WriteHeader(http.StatusBadRequest)
+			http.Error(writer, err.Error(), http.StatusBadRequest)
 		} else {
-			writer.WriteHeader(http.StatusInternalServerError)
+			http.Error(writer, err.Error(), http.StatusInternalServerError)
 		}
-		_, _ = writer.Write([]byte(err.Error()))
 		return
 	}
 	if len(hourlyAverageResponseTime) == 0 {
-		writer.WriteHeader(http.StatusNoContent)
-		_, _ = writer.Write(nil)
+		http.Error(writer, "", http.StatusNoContent)
 		return
 	}
 	series := chart.TimeSeries{
@@ -114,6 +112,9 @@ func ResponseTimeChart(writer http.ResponseWriter, r *http.Request) {
 		Series: []chart.Series{series},
 	}
 	writer.Header().Set("Content-Type", "image/svg+xml")
+	writer.Header().Set("Cache-Control", "no-cache, no-store")
+	writer.Header().Set("Expires", "0")
+	writer.WriteHeader(http.StatusOK)
 	if err := graph.Render(chart.SVG, writer); err != nil {
 		log.Println("[handler][ResponseTimeChart] Failed to render response time chart:", err.Error())
 		return

controller/handler/chart_test.go

@@ -66,7 +66,7 @@ func TestResponseTimeChart(t *testing.T) {
 	}
 	for _, scenario := range scenarios {
 		t.Run(scenario.Name, func(t *testing.T) {
-			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			request, _ := http.NewRequest("GET", scenario.Path, http.NoBody)
 			if scenario.Gzip {
 				request.Header.Set("Accept-Encoding", "gzip")
 			}

controller/handler/config.go

@@ -0,0 +1,26 @@
+package handler
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/TwiN/gatus/v3/security"
+)
+
+// ConfigHandler is a handler that returns information for the front end of the application.
+type ConfigHandler struct {
+	securityConfig *security.Config
+}
+
+func (handler ConfigHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	hasOIDC := false
+	isAuthenticated := true // Default to true if no security config is set
+	if handler.securityConfig != nil {
+		hasOIDC = handler.securityConfig.OIDC != nil
+		isAuthenticated = handler.securityConfig.IsAuthenticated(r)
+	}
+	// Return the config
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	_, _ = w.Write([]byte(fmt.Sprintf(`{"oidc":%v,"authenticated":%v}`, hasOIDC, isAuthenticated)))
+}

controller/handler/config_test.go

@@ -0,0 +1,34 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/TwiN/gatus/v3/security"
+	"github.com/gorilla/mux"
+)
+
+func TestConfigHandler_ServeHTTP(t *testing.T) {
+	securityConfig := &security.Config{
+		OIDC: &security.OIDCConfig{
+			IssuerURL:       "https://sso.gatus.io/",
+			RedirectURL:     "http://localhost:80/authorization-code/callback",
+			Scopes:          []string{"openid"},
+			AllowedSubjects: []string{"user1@example.com"},
+		},
+	}
+	handler := ConfigHandler{securityConfig: securityConfig}
+	// Create a fake router. We're doing this because I need the gate to be initialized.
+	securityConfig.ApplySecurityMiddleware(mux.NewRouter())
+	// Test the config handler
+	request, _ := http.NewRequest("GET", "/api/v1/config", http.NoBody)
+	responseRecorder := httptest.NewRecorder()
+	handler.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusOK {
+		t.Error("expected code to be 200, but was", responseRecorder.Code)
+	}
+	if responseRecorder.Body.String() != `{"oidc":true,"authenticated":false}` {
+		t.Error("expected body to be `{\"oidc\":true,\"authenticated\":false}`, but was", responseRecorder.Body.String())
+	}
+}

controller/handler/cors.go

@@ -4,7 +4,11 @@ import "net/http"
 
 func DevelopmentCORS(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Access-Control-Allow-Credentials", "true")
 		w.Header().Set("Access-Control-Allow-Origin", "http://localhost:8081")
+		if r.Method == "OPTIONS" {
+			return
+		}
 		next.ServeHTTP(w, r)
 	})
 }

controller/handler/endpoint_status_test.go

@@ -139,7 +139,7 @@ func TestEndpointStatus(t *testing.T) {
 	}
 	for _, scenario := range scenarios {
 		t.Run(scenario.Name, func(t *testing.T) {
-			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			request, _ := http.NewRequest("GET", scenario.Path, http.NoBody)
 			if scenario.Gzip {
 				request.Header.Set("Accept-Encoding", "gzip")
 			}
@@ -211,7 +211,7 @@ func TestEndpointStatuses(t *testing.T) {
 
 	for _, scenario := range scenarios {
 		t.Run(scenario.Name, func(t *testing.T) {
-			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			request, _ := http.NewRequest("GET", scenario.Path, http.NoBody)
 			responseRecorder := httptest.NewRecorder()
 			router.ServeHTTP(responseRecorder, request)
 			if responseRecorder.Code != scenario.ExpectedCode {

controller/handler/favicon_test.go

@@ -22,7 +22,7 @@ func TestFavIcon(t *testing.T) {
 	}
 	for _, scenario := range scenarios {
 		t.Run(scenario.Name, func(t *testing.T) {
-			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			request, _ := http.NewRequest("GET", scenario.Path, http.NoBody)
 			responseRecorder := httptest.NewRecorder()
 			router.ServeHTTP(responseRecorder, request)
 			if responseRecorder.Code != scenario.ExpectedCode {

controller/handler/gzip.go

@@ -3,7 +3,6 @@ package handler
 import (
 	"compress/gzip"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"strings"
 	"sync"
@@ -11,7 +10,7 @@ import (
 
 var gzPool = sync.Pool{
 	New: func() interface{} {
-		return gzip.NewWriter(ioutil.Discard)
+		return gzip.NewWriter(io.Discard)
 	},
 }
 

controller/handler/handler.go

@@ -15,21 +15,34 @@ func CreateRouter(staticFolder string, securityConfig *security.Config, uiConfig
 	if enabledMetrics {
 		router.Handle("/metrics", promhttp.Handler()).Methods("GET")
 	}
+	api := router.PathPrefix("/api").Subrouter()
+	protected := api.PathPrefix("/").Subrouter()
+	unprotected := api.PathPrefix("/").Subrouter()
+	if securityConfig != nil {
+		if err := securityConfig.RegisterHandlers(router); err != nil {
+			panic(err)
+		}
+		if err := securityConfig.ApplySecurityMiddleware(protected); err != nil {
+			panic(err)
+		}
+	}
+	// Endpoints
+	unprotected.Handle("/v1/config", ConfigHandler{securityConfig: securityConfig}).Methods("GET")
+	protected.HandleFunc("/v1/endpoints/statuses", EndpointStatuses).Methods("GET") // No GzipHandler for this one, because we cache the content as Gzipped already
+	protected.HandleFunc("/v1/endpoints/{key}/statuses", GzipHandlerFunc(EndpointStatus)).Methods("GET")
+	unprotected.HandleFunc("/v1/endpoints/{key}/uptimes/{duration}/badge.svg", UptimeBadge).Methods("GET")
+	unprotected.HandleFunc("/v1/endpoints/{key}/response-times/{duration}/badge.svg", ResponseTimeBadge).Methods("GET")
+	unprotected.HandleFunc("/v1/endpoints/{key}/response-times/{duration}/chart.svg", ResponseTimeChart).Methods("GET")
+	// XXX: Remove the lines between this and the next XXX comment in v4.0.0
+	protected.HandleFunc("/v1/services/statuses", EndpointStatuses).Methods("GET") // No GzipHandler for this one, because we cache the content as Gzipped already
+	protected.HandleFunc("/v1/services/{key}/statuses", GzipHandlerFunc(EndpointStatus)).Methods("GET")
+	unprotected.HandleFunc("/v1/services/{key}/uptimes/{duration}/badge.svg", UptimeBadge).Methods("GET")
+	unprotected.HandleFunc("/v1/services/{key}/response-times/{duration}/badge.svg", ResponseTimeBadge).Methods("GET")
+	unprotected.HandleFunc("/v1/services/{key}/response-times/{duration}/chart.svg", ResponseTimeChart).Methods("GET")
+	// XXX: Remove the lines between this and the previous XXX comment in v4.0.0
+	// Misc
 	router.Handle("/health", health.Handler().WithJSON(true)).Methods("GET")
 	router.HandleFunc("/favicon.ico", FavIcon(staticFolder)).Methods("GET")
-	// Endpoints
-	router.HandleFunc("/api/v1/endpoints/statuses", secureIfNecessary(securityConfig, EndpointStatuses)).Methods("GET") // No GzipHandler for this one, because we cache the content as Gzipped already
-	router.HandleFunc("/api/v1/endpoints/{key}/statuses", secureIfNecessary(securityConfig, GzipHandlerFunc(EndpointStatus))).Methods("GET")
-	router.HandleFunc("/api/v1/endpoints/{key}/uptimes/{duration}/badge.svg", UptimeBadge).Methods("GET")
-	router.HandleFunc("/api/v1/endpoints/{key}/response-times/{duration}/badge.svg", ResponseTimeBadge).Methods("GET")
-	router.HandleFunc("/api/v1/endpoints/{key}/response-times/{duration}/chart.svg", ResponseTimeChart).Methods("GET")
-	// XXX: Remove the lines between this and the next XXX comment in v4.0.0
-	router.HandleFunc("/api/v1/services/statuses", secureIfNecessary(securityConfig, EndpointStatuses)).Methods("GET") // No GzipHandler for this one, because we cache the content as Gzipped already
-	router.HandleFunc("/api/v1/services/{key}/statuses", secureIfNecessary(securityConfig, GzipHandlerFunc(EndpointStatus))).Methods("GET")
-	router.HandleFunc("/api/v1/services/{key}/uptimes/{duration}/badge.svg", UptimeBadge).Methods("GET")
-	router.HandleFunc("/api/v1/services/{key}/response-times/{duration}/badge.svg", ResponseTimeBadge).Methods("GET")
-	router.HandleFunc("/api/v1/services/{key}/response-times/{duration}/chart.svg", ResponseTimeChart).Methods("GET")
-	// XXX: Remove the lines between this and the previous XXX comment in v4.0.0
 	// SPA
 	router.HandleFunc("/services/{name}", SinglePageApplication(staticFolder, uiConfig)).Methods("GET") // XXX: Remove this in v4.0.0
 	router.HandleFunc("/endpoints/{name}", SinglePageApplication(staticFolder, uiConfig)).Methods("GET")
@@ -38,10 +51,3 @@ func CreateRouter(staticFolder string, securityConfig *security.Config, uiConfig
 	router.PathPrefix("/").Handler(GzipHandler(http.FileServer(http.Dir(staticFolder))))
 	return router
 }
-
-func secureIfNecessary(securityConfig *security.Config, handler http.HandlerFunc) http.HandlerFunc {
-	if securityConfig != nil && securityConfig.IsValid() {
-		return security.Handler(handler, securityConfig)
-	}
-	return handler
-}

controller/handler/handler_test.go

@@ -44,7 +44,7 @@ func TestCreateRouter(t *testing.T) {
 	}
 	for _, scenario := range scenarios {
 		t.Run(scenario.Name, func(t *testing.T) {
-			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			request, _ := http.NewRequest("GET", scenario.Path, http.NoBody)
 			if scenario.Gzip {
 				request.Header.Set("Accept-Encoding", "gzip")
 			}

controller/handler/spa_test.go

@@ -56,7 +56,7 @@ func TestSinglePageApplication(t *testing.T) {
 	}
 	for _, scenario := range scenarios {
 		t.Run(scenario.Name, func(t *testing.T) {
-			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			request, _ := http.NewRequest("GET", scenario.Path, http.NoBody)
 			if scenario.Gzip {
 				request.Header.Set("Accept-Encoding", "gzip")
 			}

controller/handler/util_test.go

@@ -54,7 +54,7 @@ func TestExtractPageAndPageSizeFromRequest(t *testing.T) {
 	}
 	for _, scenario := range scenarios {
 		t.Run("page-"+scenario.Page+"-pageSize-"+scenario.PageSize, func(t *testing.T) {
-			request, _ := http.NewRequest("GET", fmt.Sprintf("/api/v1/statuses?page=%s&pageSize=%s", scenario.Page, scenario.PageSize), nil)
+			request, _ := http.NewRequest("GET", fmt.Sprintf("/api/v1/statuses?page=%s&pageSize=%s", scenario.Page, scenario.PageSize), http.NoBody)
 			actualPage, actualPageSize := extractPageAndPageSizeFromRequest(request)
 			if actualPage != scenario.ExpectedPage {
 				t.Errorf("expected %d, got %d", scenario.ExpectedPage, actualPage)

core/endpoint.go

@@ -5,7 +5,7 @@ import (
 	"crypto/x509"
 	"encoding/json"
 	"errors"
-	"io/ioutil"
+	"io"
 	"net"
 	"net/http"
 	"net/url"
@@ -41,6 +41,9 @@ var (
 
 	// ErrEndpointWithNoName is the error with which Gatus will panic if an endpoint is configured with no name
 	ErrEndpointWithNoName = errors.New("you must specify a name for each endpoint")
+
+	// ErrEndpointWithInvalidNameOrGroup is the error with which Gatus will panic if an endpoint has an invalid character where it shouldn't
+	ErrEndpointWithInvalidNameOrGroup = errors.New("endpoint name and group must not have \" or \\")
 )
 
 // Endpoint is the configuration of a monitored
@@ -108,7 +111,9 @@ func (endpoint *Endpoint) ValidateAndSetDefaults() error {
 	if endpoint.ClientConfig == nil {
 		endpoint.ClientConfig = client.GetDefaultConfig()
 	} else {
-		endpoint.ClientConfig.ValidateAndSetDefaults()
+		if err := endpoint.ClientConfig.ValidateAndSetDefaults(); err != nil {
+			return err
+		}
 	}
 	if endpoint.UIConfig == nil {
 		endpoint.UIConfig = ui.GetDefaultConfig()
@@ -132,16 +137,16 @@ func (endpoint *Endpoint) ValidateAndSetDefaults() error {
 		endpoint.Headers[ContentTypeHeader] = "application/json"
 	}
 	for _, endpointAlert := range endpoint.Alerts {
-		if endpointAlert.FailureThreshold <= 0 {
-			endpointAlert.FailureThreshold = 3
-		}
-		if endpointAlert.SuccessThreshold <= 0 {
-			endpointAlert.SuccessThreshold = 2
+		if err := endpointAlert.ValidateAndSetDefaults(); err != nil {
+			return err
 		}
 	}
 	if len(endpoint.Name) == 0 {
 		return ErrEndpointWithNoName
 	}
+	if strings.ContainsAny(endpoint.Name, "\"\\") || strings.ContainsAny(endpoint.Group, "\"\\") {
+		return ErrEndpointWithInvalidNameOrGroup
+	}
 	if len(endpoint.URL) == 0 {
 		return ErrEndpointWithNoURL
 	}
@@ -159,6 +164,14 @@ func (endpoint *Endpoint) ValidateAndSetDefaults() error {
 	return nil
 }
 
+// DisplayName returns an identifier made up of the Name and, if not empty, the Group.
+func (endpoint Endpoint) DisplayName() string {
+	if len(endpoint.Group) > 0 {
+		return endpoint.Group + "/" + endpoint.Name
+	}
+	return endpoint.Name
+}
+
 // Key returns the unique key for the Endpoint
 func (endpoint Endpoint) Key() string {
 	return util.ConvertGroupAndEndpointNameToKey(endpoint.Group, endpoint.Name)
@@ -184,6 +197,9 @@ func (endpoint *Endpoint) EvaluateHealth() *Result {
 	result.body = nil
 	// Clean up parameters that we don't need to keep in the results
 	if endpoint.UIConfig.HideHostname {
+		for errIdx, errorString := range result.Errors {
+			result.Errors[errIdx] = strings.ReplaceAll(errorString, result.Hostname, "<redacted>")
+		}
 		result.Hostname = ""
 	}
 	return result
@@ -259,7 +275,7 @@ func (endpoint *Endpoint) call(result *Result) {
 		result.Connected = response.StatusCode > 0
 		// Only read the body if there's a condition that uses the BodyPlaceholder
 		if endpoint.needsToReadBody() {
-			result.body, err = ioutil.ReadAll(response.Body)
+			result.body, err = io.ReadAll(response.Body)
 			if err != nil {
 				result.AddError(err.Error())
 			}

core/endpoint_test.go

@@ -1,13 +1,14 @@
 package core
 
 import (
-	"io/ioutil"
+	"io"
 	"strings"
 	"testing"
 	"time"
 
 	"github.com/TwiN/gatus/v3/alerting/alert"
 	"github.com/TwiN/gatus/v3/client"
+	"github.com/TwiN/gatus/v3/core/ui"
 )
 
 func TestEndpoint_IsEnabled(t *testing.T) {
@@ -245,7 +246,7 @@ func TestEndpoint_buildHTTPRequestWithGraphQLEnabled(t *testing.T) {
 	if contentType := request.Header.Get(ContentTypeHeader); contentType != "application/json" {
 		t.Error("request.Header.Content-Type should've been application/json, but was", contentType)
 	}
-	body, _ := ioutil.ReadAll(request.Body)
+	body, _ := io.ReadAll(request.Body)
 	if !strings.HasPrefix(string(body), "{\"query\":") {
 		t.Error("request.body should've started with '{\"query\":', but it didn't:", string(body))
 	}
@@ -270,6 +271,9 @@ func TestIntegrationEvaluateHealth(t *testing.T) {
 	if !result.Success {
 		t.Error("Because all conditions passed, this should have been a success")
 	}
+	if result.Hostname != "twin.sh" {
+		t.Error("result.Hostname should've been twin.sh, but was", result.Hostname)
+	}
 }
 
 func TestIntegrationEvaluateHealthWithFailure(t *testing.T) {
@@ -288,7 +292,53 @@ func TestIntegrationEvaluateHealthWithFailure(t *testing.T) {
 		t.Error("Because the connection has been established, result.Connected should've been true")
 	}
 	if result.Success {
-		t.Error("Because one of the conditions failed, success should have been false")
+		t.Error("Because one of the conditions failed, result.Success should have been false")
+	}
+}
+
+func TestIntegrationEvaluateHealthWithInvalidCondition(t *testing.T) {
+	condition := Condition("[STATUS] invalid 200")
+	endpoint := Endpoint{
+		Name:       "invalid-condition",
+		URL:        "https://twin.sh/health",
+		Conditions: []*Condition{&condition},
+	}
+	if err := endpoint.ValidateAndSetDefaults(); err != nil {
+		// XXX: Should this really not return an error? After all, the condition is not valid and conditions are part of the endpoint...
+		t.Error("endpoint validation should've been successful, but wasn't")
+	}
+	result := endpoint.EvaluateHealth()
+	if result.Success {
+		t.Error("Because one of the conditions was invalid, result.Success should have been false")
+	}
+	if len(result.Errors) == 0 {
+		t.Error("There should've been an error")
+	}
+}
+
+func TestIntegrationEvaluateHealthWithError(t *testing.T) {
+	condition := Condition("[STATUS] == 200")
+	endpoint := Endpoint{
+		Name:       "invalid-host",
+		URL:        "http://invalid/health",
+		Conditions: []*Condition{&condition},
+		UIConfig: &ui.Config{
+			HideHostname: true,
+		},
+	}
+	endpoint.ValidateAndSetDefaults()
+	result := endpoint.EvaluateHealth()
+	if result.Success {
+		t.Error("Because one of the conditions was invalid, result.Success should have been false")
+	}
+	if len(result.Errors) == 0 {
+		t.Error("There should've been an error")
+	}
+	if !strings.Contains(result.Errors[0], "<redacted>") {
+		t.Error("result.Errors[0] should've had the hostname redacted because ui.hide-hostname is set to true")
+	}
+	if result.Hostname != "" {
+		t.Error("result.Hostname should've been empty because ui.hide-hostname is set to true")
 	}
 }
 

go.mod

@@ -3,36 +3,49 @@ module github.com/TwiN/gatus/v3
 go 1.17
 
 require (
+	github.com/TwiN/g8 v1.3.0
 	github.com/TwiN/gocache v1.2.4
-	github.com/TwiN/health v1.0.1
-	github.com/beorn7/perks v1.0.1 // indirect
-	github.com/cespare/xxhash/v2 v2.1.2 // indirect
+	github.com/TwiN/gocache/v2 v2.0.0
+	github.com/TwiN/health v1.3.0
+	github.com/coreos/go-oidc/v3 v3.1.0
 	github.com/go-ping/ping v0.0.0-20210911151512-381826476871
-	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 // indirect
-	github.com/golang/protobuf v1.5.2 // indirect
-	github.com/google/uuid v1.3.0 // indirect
+	github.com/google/uuid v1.3.0
 	github.com/gorilla/mux v1.8.0
-	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 // indirect
 	github.com/lib/pq v1.10.3
-	github.com/mattn/go-isatty v0.0.14 // indirect
-	github.com/matttproud/golang_protobuf_extensions v1.0.1 // indirect
 	github.com/miekg/dns v1.1.43
 	github.com/prometheus/client_golang v1.11.0
+	github.com/wcharczuk/go-chart/v2 v2.1.0
+	golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9
+	golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c
+	gopkg.in/mail.v2 v2.3.1
+	gopkg.in/yaml.v2 v2.4.0
+	modernc.org/sqlite v1.13.1
+)
+
+require (
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cespare/xxhash/v2 v2.1.2 // indirect
+	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 // indirect
+	github.com/mattn/go-isatty v0.0.14 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.1 // indirect
 	github.com/prometheus/client_model v0.2.0 // indirect
 	github.com/prometheus/common v0.31.1 // indirect
 	github.com/prometheus/procfs v0.7.3 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20200410134404-eec4a21b6bb0 // indirect
-	github.com/wcharczuk/go-chart/v2 v2.1.0
 	go.etcd.io/bbolt v1.3.6 // indirect
 	golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d // indirect
 	golang.org/x/mod v0.5.1 // indirect
-	golang.org/x/net v0.0.0-20210929193557-e81a3d93ecf6 // indirect
+	golang.org/x/net v0.0.0-20211209124913-491a49abca63 // indirect
 	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c // indirect
 	golang.org/x/sys v0.0.0-20211003122950-b1ebd4e1001c // indirect
 	golang.org/x/tools v0.1.7 // indirect
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
+	google.golang.org/appengine v1.6.6 // indirect
 	google.golang.org/protobuf v1.27.1 // indirect
-	gopkg.in/yaml.v2 v2.4.0
+	gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc // indirect
+	gopkg.in/square/go-jose.v2 v2.5.1 // indirect
 	lukechampine.com/uint128 v1.1.1 // indirect
 	modernc.org/cc/v3 v3.35.8 // indirect
 	modernc.org/ccgo/v3 v3.12.16 // indirect
@@ -40,7 +53,6 @@ require (
 	modernc.org/mathutil v1.4.1 // indirect
 	modernc.org/memory v1.0.5 // indirect
 	modernc.org/opt v0.1.1 // indirect
-	modernc.org/sqlite v1.13.1
 	modernc.org/strutil v1.1.1 // indirect
 	modernc.org/token v1.0.0 // indirect
 )

go.sum

@@ -33,10 +33,14 @@ cloud.google.com/go/storage v1.10.0/go.mod h1:FLPqc6j+Ki4BU591ie1oL6qBQGu2Bl/tZ9
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
+github.com/TwiN/g8 v1.3.0 h1:mNv3R35GhDn1gEV0BKMl1oupZ1tDtOWPTHUKu+W/k3U=
+github.com/TwiN/g8 v1.3.0/go.mod h1:SiIdItS0agSUloFqdQQt/RObB2jGSq+nnE9WfFv3RIo=
 github.com/TwiN/gocache v1.2.4 h1:AfJ1YRcxtQ/zZEN61URDwk/dwFG7LSRenU5qIm9dQzo=
 github.com/TwiN/gocache v1.2.4/go.mod h1:BjabsQQy6z5uHDorHa4LJVPEzFeitLIDbCtdv3gc1gA=
-github.com/TwiN/health v1.0.1 h1:Q8lE6mTMPG4A5nHXq5Xa+NY4Y8LkQdRBWh1ReUkuc6Y=
-github.com/TwiN/health v1.0.1/go.mod h1:Bt+lEvSi6C/9NWb7OoGmUmgtS4dfPeMM9EINnURv5dE=
+github.com/TwiN/gocache/v2 v2.0.0 h1:CPbDNKdSJpmBkh7aWcO7D3KK1yWaMlwX+3dsBPE8/so=
+github.com/TwiN/gocache/v2 v2.0.0/go.mod h1:j4MABVaia2Tp53ERWc/3l4YxkswtPjB2hQzmL/kD/VQ=
+github.com/TwiN/health v1.3.0 h1:xw90rZqg0NH5MRkVHzlgtDdP+EQd43v3yMqQVtYlGHg=
+github.com/TwiN/health v1.3.0/go.mod h1:Bt+lEvSi6C/9NWb7OoGmUmgtS4dfPeMM9EINnURv5dE=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
@@ -55,7 +59,10 @@ github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5P
 github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=
+github.com/coreos/go-oidc/v3 v3.1.0 h1:6avEvcdvTa1qYsOZ6I5PRkSYHzpTNWgKYmaJfaYbrRw=
+github.com/coreos/go-oidc/v3 v3.1.0/go.mod h1:rEJ/idjfUyfkBit1eI1fvyr+64/g9dcKpAm8MJMesvo=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dustin/go-humanize v1.0.0 h1:VSnTsYCnlFHaM2/igO1h6X3HA71jcobQuxemgkq4zYo=
 github.com/dustin/go-humanize v1.0.0/go.mod h1:HtrtbFcZ19U5GC7JDqmcUSB87Iq5E25KnS6fMYU6eOk=
@@ -190,6 +197,7 @@ github.com/onsi/gomega v1.10.2/go.mod h1:iN09h71vgCQne3DLsj+A5owkum+a2tYe+TOCB1y
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_golang v0.9.1/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXPKyh/dDVn+NZz0KFw=
 github.com/prometheus/client_golang v1.0.0/go.mod h1:db9x61etRT2tGnBNRi70OPL5FsnadC4Ky3P0J6CfImo=
@@ -223,6 +231,8 @@ github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
+github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/tidwall/redcon v1.3.2/go.mod h1:bdYBm4rlcWpst2XMwKVzWDF9CoUxEbUmM7CQrKeOZas=
 github.com/wcharczuk/go-chart/v2 v2.1.0 h1:tY2slqVQ6bN+yHSnDYwZebLQFkphK4WNrVwnt7CJZ2I=
 github.com/wcharczuk/go-chart/v2 v2.1.0/go.mod h1:yx7MvAVNcP/kN9lKXM/NTce4au4DFN99j6i1OwDclNA=
@@ -244,6 +254,7 @@ golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACk
 golang.org/x/crypto v0.0.0-20190510104115-cbcb75029529/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20190605123033-f99c8df09eb5/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9 h1:psW17arqaxU48Z5kZ0CQnkZWQJsqcURM6tKiBApRjXI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
@@ -304,6 +315,7 @@ golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLL
 golang.org/x/net v0.0.0-20200301022130-244492dfa37a/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20200324143707-d3edc9973b7e/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
 golang.org/x/net v0.0.0-20200501053045-e0ff5e5a1de5/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
+golang.org/x/net v0.0.0-20200505041828-1ed23360d12c/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
 golang.org/x/net v0.0.0-20200506145744-7e3656a0809f/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
 golang.org/x/net v0.0.0-20200513185701-a91f0712d120/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
 golang.org/x/net v0.0.0-20200520004742-59133d7f0dd7/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
@@ -316,13 +328,14 @@ golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v
 golang.org/x/net v0.0.0-20210316092652-d523dce5a7f4/go.mod h1:RBQZq4jEuRlivfhVLdyRGr576XBO4/greRjx4P4O3yc=
 golang.org/x/net v0.0.0-20210525063256-abc453219eb5/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/net v0.0.0-20210929193557-e81a3d93ecf6 h1:Z04ewVs7JhXaYkmDhBERPi41gnltfQpMWDnTnQbaCqk=
-golang.org/x/net v0.0.0-20210929193557-e81a3d93ecf6/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/net v0.0.0-20211209124913-491a49abca63 h1:iocB37TsdFuN6IBRZ+ry36wrkoV51/tl5vOWqkcPGvY=
+golang.org/x/net v0.0.0-20211209124913-491a49abca63/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20191202225959-858c2ad4c8b6/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
+golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c h1:pkQiBZBvdos9qq4wBAHqlzuZHEXo07pqV06ef90u1WI=
 golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -466,6 +479,7 @@ google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7
 google.golang.org/appengine v1.5.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/appengine v1.6.1/go.mod h1:i06prIuMbXzDqacNJfV5OdTW448YApPu5ww/cMBSeb0=
 google.golang.org/appengine v1.6.5/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=
+google.golang.org/appengine v1.6.6 h1:lMO5rYAqUxkmaj76jAkRUvt5JZgFymx/+Q5Mzfivuhc=
 google.golang.org/appengine v1.6.6/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/genproto v0.0.0-20190307195333-5fe7a883aa19/go.mod h1:VzzqZJRnGkLBvHegQrXjBqPurQTc5/KpmUdxsrq26oE=
@@ -523,12 +537,18 @@ google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQ
 google.golang.org/protobuf v1.27.1 h1:SnqbnDw1V7RiZcXPx5MEeqPv2s79L9i7BJUlG/+RurQ=
 google.golang.org/protobuf v1.27.1/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
+gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc h1:2gGKlE2+asNV9m7xrywl36YYNnBG5ZQ0r/BOOxqPpmk=
+gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc/go.mod h1:m7x9LTH6d71AHyAX77c9yqWCCa3UKHcVEj9y7hAtKDk=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
 gopkg.in/fsnotify.v1 v1.4.7/go.mod h1:Tz8NjZHkW78fSQdbUxIjBTcgA1z1m8ZHf0WmKUhAMys=
+gopkg.in/mail.v2 v2.3.1 h1:WYFn/oANrAGP2C0dcV6/pbkPzv8yGzqTjPmTeO7qoXk=
+gopkg.in/mail.v2 v2.3.1/go.mod h1:htwXN1Qh09vZJ1NVKxQqHPBaCBbzKhp5GzuJEA4VJWw=
+gopkg.in/square/go-jose.v2 v2.5.1 h1:7odma5RETjNHWJnR32wx8t+Io4djHE1PqxCFx3iiZ2w=
+gopkg.in/square/go-jose.v2 v2.5.1/go.mod h1:M9dMgbHiYLoDGQrXy7OpJDJWiKiU//h+vD76mk0e1AI=
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWDmTeBkI65Dw0HsyUHuEVlX15mw=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

main.go

@@ -88,6 +88,8 @@ func listenToConfigurationFileChanges(cfg *config.Config) {
 		time.Sleep(30 * time.Second)
 		if cfg.HasLoadedConfigurationFileBeenModified() {
 			log.Println("[main][listenToConfigurationFileChanges] Configuration file has been modified")
+			stop()
+			time.Sleep(time.Second) // Wait a bit to make sure everything is done.
 			save()
 			updatedConfig, err := loadConfiguration()
 			if err != nil {
@@ -101,7 +103,7 @@ func listenToConfigurationFileChanges(cfg *config.Config) {
 					panic(err)
 				}
 			}
-			stop()
+			initializeStorage(updatedConfig)
 			start(updatedConfig)
 			return
 		}

metric/metric.go

@@ -1,9 +1,7 @@
 package metric
 
 import (
-	"fmt"
 	"strconv"
-	"sync"
 
 	"github.com/TwiN/gatus/v3/core"
 	"github.com/prometheus/client_golang/prometheus"
@@ -11,24 +9,19 @@ import (
 )
 
 var (
-	gauges = map[string]*prometheus.GaugeVec{}
-	rwLock sync.RWMutex
+	// This will be initialized once PublishMetricsForEndpoint.
+	// The reason why we're doing this is that if metrics are disabled, we don't want to initialize it unnecessarily.
+	resultCount *prometheus.CounterVec = nil
 )
 
 // PublishMetricsForEndpoint publishes metrics for the given endpoint and its result.
 // These metrics will be exposed at /metrics if the metrics are enabled
 func PublishMetricsForEndpoint(endpoint *core.Endpoint, result *core.Result) {
-	rwLock.Lock()
-	gauge, exists := gauges[fmt.Sprintf("%s_%s", endpoint.Name, endpoint.URL)]
-	if !exists {
-		gauge = promauto.NewGaugeVec(prometheus.GaugeOpts{
-			Subsystem: "gatus",
-			Name:      "tasks",
-			// TODO: remove the "service" key in v4.0.0, as it is only kept for backward compatibility
-			ConstLabels: prometheus.Labels{"service": endpoint.Name, "endpoint": endpoint.Name, "url": endpoint.URL},
-		}, []string{"status", "success"})
-		gauges[fmt.Sprintf("%s_%s", endpoint.Name, endpoint.URL)] = gauge
+	if resultCount == nil {
+		resultCount = promauto.NewCounterVec(prometheus.CounterOpts{
+			Name: "gatus_results_total",
+			Help: "Number of results per endpoint",
+		}, []string{"key", "group", "name", "success"})
 	}
-	rwLock.Unlock()
-	gauge.WithLabelValues(strconv.Itoa(result.HTTPStatus), strconv.FormatBool(result.Success)).Inc()
+	resultCount.WithLabelValues(endpoint.Key(), endpoint.Group, endpoint.Name, strconv.FormatBool(result.Success)).Inc()
 }

security/basic.go

@@ -0,0 +1,26 @@
+package security
+
+import "log"
+
+// BasicConfig is the configuration for Basic authentication
+type BasicConfig struct {
+	// Username is the name which will need to be used for a successful authentication
+	Username string `yaml:"username"`
+
+	// PasswordSha512Hash is the SHA512 hash of the password which will need to be used for a successful authentication
+	// XXX: Remove this on v4.0.0
+	// Deprecated: Use PasswordBcryptHashBase64Encoded instead
+	PasswordSha512Hash string `yaml:"password-sha512"`
+
+	// PasswordBcryptHashBase64Encoded is the base64 encoded string of the Bcrypt hash of the password to use to
+	// authenticate using basic auth.
+	PasswordBcryptHashBase64Encoded string `yaml:"password-bcrypt-base64"`
+}
+
+// isValid returns whether the basic security configuration is valid or not
+func (c *BasicConfig) isValid() bool {
+	if len(c.PasswordSha512Hash) > 0 {
+		log.Println("WARNING: security.basic.password-sha512 has been deprecated in favor of security.basic.password-bcrypt-base64")
+	}
+	return len(c.Username) > 0 && (len(c.PasswordSha512Hash) == 128 || len(c.PasswordBcryptHashBase64Encoded) > 0)
+}

security/basic_test.go

@@ -0,0 +1,43 @@
+package security
+
+import "testing"
+
+func TestBasicConfig_IsValidUsingSHA512(t *testing.T) {
+	basicConfig := &BasicConfig{
+		Username:           "admin",
+		PasswordSha512Hash: Sha512("test"),
+	}
+	if !basicConfig.isValid() {
+		t.Error("basicConfig should've been valid")
+	}
+}
+
+func TestBasicConfig_IsValidWhenPasswordIsInvalidUsingSHA512(t *testing.T) {
+	basicConfig := &BasicConfig{
+		Username:           "admin",
+		PasswordSha512Hash: "",
+	}
+	if basicConfig.isValid() {
+		t.Error("basicConfig shouldn't have been valid")
+	}
+}
+
+func TestBasicConfig_IsValidUsingBcrypt(t *testing.T) {
+	basicConfig := &BasicConfig{
+		Username:                        "admin",
+		PasswordBcryptHashBase64Encoded: "JDJhJDA4JDFoRnpPY1hnaFl1OC9ISlFsa21VS09wOGlPU1ZOTDlHZG1qeTFvb3dIckRBUnlHUmNIRWlT",
+	}
+	if !basicConfig.isValid() {
+		t.Error("basicConfig should've been valid")
+	}
+}
+
+func TestBasicConfig_IsValidWhenPasswordIsInvalidUsingBcrypt(t *testing.T) {
+	basicConfig := &BasicConfig{
+		Username:                        "admin",
+		PasswordBcryptHashBase64Encoded: "",
+	}
+	if basicConfig.isValid() {
+		t.Error("basicConfig shouldn't have been valid")
+	}
+}

security/config.go

@@ -1,25 +1,109 @@
 package security
 
+import (
+	"encoding/base64"
+	"net/http"
+	"strings"
+
+	"github.com/TwiN/g8"
+	"github.com/gorilla/mux"
+	"golang.org/x/crypto/bcrypt"
+)
+
+const (
+	cookieNameState   = "gatus_state"
+	cookieNameNonce   = "gatus_nonce"
+	cookieNameSession = "gatus_session"
+)
+
 // Config is the security configuration for Gatus
 type Config struct {
-	Basic *BasicConfig `yaml:"basic"`
+	Basic *BasicConfig `yaml:"basic,omitempty"`
+	OIDC  *OIDCConfig  `yaml:"oidc,omitempty"`
+
+	gate *g8.Gate
 }
 
 // IsValid returns whether the security configuration is valid or not
 func (c *Config) IsValid() bool {
-	return c.Basic != nil && c.Basic.IsValid()
+	return (c.Basic != nil && c.Basic.isValid()) || (c.OIDC != nil && c.OIDC.isValid())
 }
 
-// BasicConfig is the configuration for Basic authentication
-type BasicConfig struct {
-	// Username is the name which will need to be used for a successful authentication
-	Username string `yaml:"username"`
-
-	// PasswordSha512Hash is the SHA512 hash of the password which will need to be used for a successful authentication
-	PasswordSha512Hash string `yaml:"password-sha512"`
+// RegisterHandlers registers all handlers required based on the security configuration
+func (c *Config) RegisterHandlers(router *mux.Router) error {
+	if c.OIDC != nil {
+		if err := c.OIDC.initialize(); err != nil {
+			return err
+		}
+		router.HandleFunc("/oidc/login", c.OIDC.loginHandler)
+		router.HandleFunc("/authorization-code/callback", c.OIDC.callbackHandler)
+	}
+	return nil
 }
 
-// IsValid returns whether the basic security configuration is valid or not
-func (c *BasicConfig) IsValid() bool {
-	return len(c.Username) > 0 && len(c.PasswordSha512Hash) == 128
+// ApplySecurityMiddleware applies an authentication middleware to the router passed.
+// The router passed should be a subrouter in charge of handlers that require authentication.
+func (c *Config) ApplySecurityMiddleware(api *mux.Router) error {
+	if c.OIDC != nil {
+		// We're going to use g8 for session handling
+		clientProvider := g8.NewClientProvider(func(token string) *g8.Client {
+			if _, exists := sessions.Get(token); exists {
+				return g8.NewClient(token)
+			}
+			return nil
+		})
+		customTokenExtractorFunc := func(request *http.Request) string {
+			sessionCookie, err := request.Cookie(cookieNameSession)
+			if err != nil {
+				return ""
+			}
+			return sessionCookie.Value
+		}
+		// TODO: g8: Add a way to update cookie after? would need the writer
+		authorizationService := g8.NewAuthorizationService().WithClientProvider(clientProvider)
+		c.gate = g8.New().WithAuthorizationService(authorizationService).WithCustomTokenExtractor(customTokenExtractorFunc)
+		api.Use(c.gate.Protect)
+	} else if c.Basic != nil {
+		var decodedBcryptHash []byte
+		if len(c.Basic.PasswordBcryptHashBase64Encoded) > 0 {
+			var err error
+			decodedBcryptHash, err = base64.URLEncoding.DecodeString(c.Basic.PasswordBcryptHashBase64Encoded)
+			if err != nil {
+				return err
+			}
+		}
+		api.Use(func(handler http.Handler) http.Handler {
+			return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				usernameEntered, passwordEntered, ok := r.BasicAuth()
+				if len(c.Basic.PasswordBcryptHashBase64Encoded) > 0 {
+					if !ok || usernameEntered != c.Basic.Username || bcrypt.CompareHashAndPassword(decodedBcryptHash, []byte(passwordEntered)) != nil {
+						w.Header().Set("WWW-Authenticate", "Basic")
+						w.WriteHeader(http.StatusUnauthorized)
+						_, _ = w.Write([]byte("Unauthorized"))
+						return
+					}
+				} else if len(c.Basic.PasswordSha512Hash) > 0 {
+					if !ok || usernameEntered != c.Basic.Username || Sha512(passwordEntered) != strings.ToLower(c.Basic.PasswordSha512Hash) {
+						w.Header().Set("WWW-Authenticate", "Basic")
+						w.WriteHeader(http.StatusUnauthorized)
+						_, _ = w.Write([]byte("Unauthorized"))
+						return
+					}
+				}
+				handler.ServeHTTP(w, r)
+			})
+		})
+	}
+	return nil
+}
+
+// IsAuthenticated checks whether the user is authenticated
+// If the Config does not warrant authentication, it will always return true.
+func (c *Config) IsAuthenticated(r *http.Request) bool {
+	if c.gate != nil {
+		token := c.gate.ExtractTokenFromRequest(r)
+		_, hasSession := sessions.Get(token)
+		return hasSession
+	}
+	return false
 }

security/config_test.go

@@ -1,23 +1,148 @@
 package security
 
-import "testing"
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
 
-func TestBasicConfig_IsValid(t *testing.T) {
-	basicConfig := &BasicConfig{
-		Username:           "admin",
-		PasswordSha512Hash: Sha512("test"),
+	"github.com/gorilla/mux"
+	"golang.org/x/oauth2"
+)
+
+func TestConfig_IsValid(t *testing.T) {
+	c := &Config{
+		Basic: nil,
+		OIDC:  nil,
 	}
-	if !basicConfig.IsValid() {
-		t.Error("basicConfig should've been valid")
+	if c.IsValid() {
+		t.Error("expected empty config to be valid")
 	}
 }
 
-func TestBasicConfig_IsValidWhenPasswordIsInvalid(t *testing.T) {
-	basicConfig := &BasicConfig{
-		Username:           "admin",
-		PasswordSha512Hash: "",
+func TestConfig_ApplySecurityMiddleware(t *testing.T) {
+	///////////
+	// BASIC //
+	///////////
+	// SHA512 (DEPRECATED)
+	c := &Config{Basic: &BasicConfig{
+		Username:           "john.doe",
+		PasswordSha512Hash: "6b97ed68d14eb3f1aa959ce5d49c7dc612e1eb1dafd73b1e705847483fd6a6c809f2ceb4e8df6ff9984c6298ff0285cace6614bf8daa9f0070101b6c89899e22",
+	}}
+	api := mux.NewRouter()
+	api.HandleFunc("/test", func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	})
+	if err := c.ApplySecurityMiddleware(api); err != nil {
+		t.Error("expected no error, but was", err)
 	}
-	if basicConfig.IsValid() {
-		t.Error("basicConfig shouldn't have been valid")
+	// Try to access the route without basic auth
+	request, _ := http.NewRequest("GET", "/test", http.NoBody)
+	responseRecorder := httptest.NewRecorder()
+	api.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusUnauthorized {
+		t.Error("expected code to be 401, but was", responseRecorder.Code)
+	}
+	// Try again, but with basic auth
+	request, _ = http.NewRequest("GET", "/test", http.NoBody)
+	responseRecorder = httptest.NewRecorder()
+	request.SetBasicAuth("john.doe", "hunter2")
+	api.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusOK {
+		t.Error("expected code to be 200, but was", responseRecorder.Code)
+	}
+	// Bcrypt
+	c = &Config{Basic: &BasicConfig{
+		Username:                        "john.doe",
+		PasswordBcryptHashBase64Encoded: "JDJhJDA4JDFoRnpPY1hnaFl1OC9ISlFsa21VS09wOGlPU1ZOTDlHZG1qeTFvb3dIckRBUnlHUmNIRWlT",
+	}}
+	api = mux.NewRouter()
+	api.HandleFunc("/test", func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	})
+	if err := c.ApplySecurityMiddleware(api); err != nil {
+		t.Error("expected no error, but was", err)
+	}
+	// Try to access the route without basic auth
+	request, _ = http.NewRequest("GET", "/test", http.NoBody)
+	responseRecorder = httptest.NewRecorder()
+	api.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusUnauthorized {
+		t.Error("expected code to be 401, but was", responseRecorder.Code)
+	}
+	// Try again, but with basic auth
+	request, _ = http.NewRequest("GET", "/test", http.NoBody)
+	responseRecorder = httptest.NewRecorder()
+	request.SetBasicAuth("john.doe", "hunter2")
+	api.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusOK {
+		t.Error("expected code to be 200, but was", responseRecorder.Code)
+	}
+	//////////
+	// OIDC //
+	//////////
+	api = mux.NewRouter()
+	api.HandleFunc("/test", func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	})
+	c.OIDC = &OIDCConfig{
+		IssuerURL:       "https://sso.gatus.io/",
+		RedirectURL:     "http://localhost:80/authorization-code/callback",
+		Scopes:          []string{"openid"},
+		AllowedSubjects: []string{"user1@example.com"},
+		oauth2Config:    oauth2.Config{},
+		verifier:        nil,
+	}
+	c.Basic = nil
+	if err := c.ApplySecurityMiddleware(api); err != nil {
+		t.Error("expected no error, but was", err)
+	}
+	// Try without any session cookie
+	request, _ = http.NewRequest("GET", "/test", http.NoBody)
+	responseRecorder = httptest.NewRecorder()
+	api.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusUnauthorized {
+		t.Error("expected code to be 401, but was", responseRecorder.Code)
+	}
+	// Try with a session cookie
+	request, _ = http.NewRequest("GET", "/test", http.NoBody)
+	request.AddCookie(&http.Cookie{Name: "session", Value: "123"})
+	responseRecorder = httptest.NewRecorder()
+	api.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusUnauthorized {
+		t.Error("expected code to be 401, but was", responseRecorder.Code)
+	}
+}
+
+func TestConfig_RegisterHandlers(t *testing.T) {
+	c := &Config{}
+	router := mux.NewRouter()
+	c.RegisterHandlers(router)
+	// Try to access the OIDC handler. This should fail, because the security config doesn't have OIDC
+	request, _ := http.NewRequest("GET", "/oidc/login", http.NoBody)
+	responseRecorder := httptest.NewRecorder()
+	router.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusNotFound {
+		t.Error("expected code to be 404, but was", responseRecorder.Code)
+	}
+	// Set an empty OIDC config. This should fail, because the IssuerURL is required.
+	c.OIDC = &OIDCConfig{}
+	if err := c.RegisterHandlers(router); err == nil {
+		t.Fatal("expected an error, but got none")
+	}
+	// Set the OIDC config and try again
+	c.OIDC = &OIDCConfig{
+		IssuerURL:       "https://sso.gatus.io/",
+		RedirectURL:     "http://localhost:80/authorization-code/callback",
+		Scopes:          []string{"openid"},
+		AllowedSubjects: []string{"user1@example.com"},
+	}
+	if err := c.RegisterHandlers(router); err != nil {
+		t.Fatal("expected no error, but got", err)
+	}
+	request, _ = http.NewRequest("GET", "/oidc/login", http.NoBody)
+	responseRecorder = httptest.NewRecorder()
+	router.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusFound {
+		t.Error("expected code to be 302, but was", responseRecorder.Code)
 	}
 }

security/handler.go

@@ -1,20 +0,0 @@
-package security
-
-import (
-	"net/http"
-	"strings"
-)
-
-// Handler takes care of security for a given handler with the given security configuration
-func Handler(handler http.HandlerFunc, security *Config) http.HandlerFunc {
-	return func(w http.ResponseWriter, r *http.Request) {
-		usernameEntered, passwordEntered, ok := r.BasicAuth()
-		if !ok || usernameEntered != security.Basic.Username || Sha512(passwordEntered) != strings.ToLower(security.Basic.PasswordSha512Hash) {
-			w.Header().Set("WWW-Authenticate", "Basic")
-			w.WriteHeader(http.StatusUnauthorized)
-			_, _ = w.Write([]byte("Unauthorized"))
-			return
-		}
-		handler(w, r)
-	}
-}

security/handler_test.go

@@ -1,58 +0,0 @@
-package security
-
-import (
-	"net/http"
-	"net/http/httptest"
-	"testing"
-)
-
-func mockHandler(writer http.ResponseWriter, _ *http.Request) {
-	writer.WriteHeader(200)
-}
-
-func TestHandlerWhenNotAuthenticated(t *testing.T) {
-	handler := Handler(mockHandler, &Config{&BasicConfig{
-		Username:           "john.doe",
-		PasswordSha512Hash: "6b97ed68d14eb3f1aa959ce5d49c7dc612e1eb1dafd73b1e705847483fd6a6c809f2ceb4e8df6ff9984c6298ff0285cace6614bf8daa9f0070101b6c89899e22",
-	}})
-	request, _ := http.NewRequest("GET", "/api/v1/results", nil)
-	responseRecorder := httptest.NewRecorder()
-
-	handler.ServeHTTP(responseRecorder, request)
-
-	if responseRecorder.Code != http.StatusUnauthorized {
-		t.Error("Expected code to be 401, but was", responseRecorder.Code)
-	}
-}
-
-func TestHandlerWhenAuthenticated(t *testing.T) {
-	handler := Handler(mockHandler, &Config{&BasicConfig{
-		Username:           "john.doe",
-		PasswordSha512Hash: "6b97ed68d14eb3f1aa959ce5d49c7dc612e1eb1dafd73b1e705847483fd6a6c809f2ceb4e8df6ff9984c6298ff0285cace6614bf8daa9f0070101b6c89899e22",
-	}})
-	request, _ := http.NewRequest("GET", "/api/v1/results", nil)
-	request.SetBasicAuth("john.doe", "hunter2")
-	responseRecorder := httptest.NewRecorder()
-
-	handler.ServeHTTP(responseRecorder, request)
-
-	if responseRecorder.Code != http.StatusOK {
-		t.Error("Expected code to be 200, but was", responseRecorder.Code)
-	}
-}
-
-func TestHandlerWhenAuthenticatedWithBadCredentials(t *testing.T) {
-	handler := Handler(mockHandler, &Config{&BasicConfig{
-		Username:           "john.doe",
-		PasswordSha512Hash: "6b97ed68d14eb3f1aa959ce5d49c7dc612e1eb1dafd73b1e705847483fd6a6c809f2ceb4e8df6ff9984c6298ff0285cace6614bf8daa9f0070101b6c89899e22",
-	}})
-	request, _ := http.NewRequest("GET", "/api/v1/results", nil)
-	request.SetBasicAuth("john.doe", "bad-password")
-	responseRecorder := httptest.NewRecorder()
-
-	handler.ServeHTTP(responseRecorder, request)
-
-	if responseRecorder.Code != http.StatusUnauthorized {
-		t.Error("Expected code to be 401, but was", responseRecorder.Code)
-	}
-}

security/oidc.go

@@ -0,0 +1,141 @@
+package security
+
+import (
+	"context"
+	"log"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/coreos/go-oidc/v3/oidc"
+	"github.com/google/uuid"
+	"golang.org/x/oauth2"
+)
+
+// OIDCConfig is the configuration for OIDC authentication
+type OIDCConfig struct {
+	IssuerURL       string   `yaml:"issuer-url"`   // e.g. https://dev-12345678.okta.com
+	RedirectURL     string   `yaml:"redirect-url"` // e.g. http://localhost:8080/authorization-code/callback
+	ClientID        string   `yaml:"client-id"`
+	ClientSecret    string   `yaml:"client-secret"`
+	Scopes          []string `yaml:"scopes"`           // e.g. ["openid"]
+	AllowedSubjects []string `yaml:"allowed-subjects"` // e.g. ["user1@example.com"]. If empty, all subjects are allowed
+
+	oauth2Config oauth2.Config
+	verifier     *oidc.IDTokenVerifier
+}
+
+// isValid returns whether the basic security configuration is valid or not
+func (c *OIDCConfig) isValid() bool {
+	return len(c.IssuerURL) > 0 && len(c.RedirectURL) > 0 && strings.HasSuffix(c.RedirectURL, "/authorization-code/callback") && len(c.ClientID) > 0 && len(c.ClientSecret) > 0 && len(c.Scopes) > 0
+}
+
+func (c *OIDCConfig) initialize() error {
+	provider, err := oidc.NewProvider(context.Background(), c.IssuerURL)
+	if err != nil {
+		return err
+	}
+	c.verifier = provider.Verifier(&oidc.Config{ClientID: c.ClientID})
+	// Configure an OpenID Connect aware OAuth2 client.
+	c.oauth2Config = oauth2.Config{
+		ClientID:     c.ClientID,
+		ClientSecret: c.ClientSecret,
+		Scopes:       c.Scopes,
+		RedirectURL:  c.RedirectURL,
+		Endpoint:     provider.Endpoint(),
+	}
+	return nil
+}
+
+func (c *OIDCConfig) loginHandler(w http.ResponseWriter, r *http.Request) {
+	state, nonce := uuid.NewString(), uuid.NewString()
+	http.SetCookie(w, &http.Cookie{
+		Name:     cookieNameState,
+		Value:    state,
+		Path:     "/",
+		MaxAge:   int(time.Hour.Seconds()),
+		SameSite: http.SameSiteLaxMode,
+		HttpOnly: true,
+	})
+	http.SetCookie(w, &http.Cookie{
+		Name:     cookieNameNonce,
+		Value:    nonce,
+		Path:     "/",
+		MaxAge:   int(time.Hour.Seconds()),
+		SameSite: http.SameSiteLaxMode,
+		HttpOnly: true,
+	})
+	http.Redirect(w, r, c.oauth2Config.AuthCodeURL(state, oidc.Nonce(nonce)), http.StatusFound)
+}
+
+func (c *OIDCConfig) callbackHandler(w http.ResponseWriter, r *http.Request) {
+	// Check if there's an error
+	if len(r.URL.Query().Get("error")) > 0 {
+		http.Error(w, r.URL.Query().Get("error")+": "+r.URL.Query().Get("error_description"), http.StatusBadRequest)
+		return
+	}
+	// Ensure that the state has the expected value
+	state, err := r.Cookie(cookieNameState)
+	if err != nil {
+		http.Error(w, "state not found", http.StatusBadRequest)
+		return
+	}
+	if r.URL.Query().Get("state") != state.Value {
+		http.Error(w, "state did not match", http.StatusBadRequest)
+		return
+	}
+	// Validate token
+	oauth2Token, err := c.oauth2Config.Exchange(r.Context(), r.URL.Query().Get("code"))
+	if err != nil {
+		http.Error(w, "Error exchanging token: "+err.Error(), http.StatusInternalServerError)
+		return
+	}
+	rawIDToken, ok := oauth2Token.Extra("id_token").(string)
+	if !ok {
+		http.Error(w, "Missing 'id_token' in oauth2 token", http.StatusInternalServerError)
+		return
+	}
+	idToken, err := c.verifier.Verify(r.Context(), rawIDToken)
+	if err != nil {
+		http.Error(w, "Failed to verify id_token: "+err.Error(), http.StatusInternalServerError)
+		return
+	}
+	// Validate nonce
+	nonce, err := r.Cookie(cookieNameNonce)
+	if err != nil {
+		http.Error(w, "nonce not found", http.StatusBadRequest)
+		return
+	}
+	if idToken.Nonce != nonce.Value {
+		http.Error(w, "nonce did not match", http.StatusBadRequest)
+		return
+	}
+	if len(c.AllowedSubjects) == 0 {
+		// If there's no allowed subjects, all subjects are allowed.
+		c.setSessionCookie(w, idToken)
+		http.Redirect(w, r, "/", http.StatusFound)
+		return
+	}
+	for _, subject := range c.AllowedSubjects {
+		if strings.ToLower(subject) == strings.ToLower(idToken.Subject) {
+			c.setSessionCookie(w, idToken)
+			http.Redirect(w, r, "/", http.StatusFound)
+			return
+		}
+	}
+	log.Printf("[security][callbackHandler] Subject %s is not in the list of allowed subjects", idToken.Subject)
+	http.Redirect(w, r, "/?error=access_denied", http.StatusFound)
+}
+
+func (c *OIDCConfig) setSessionCookie(w http.ResponseWriter, idToken *oidc.IDToken) {
+	// At this point, the user has been confirmed. All that's left to do is create a session.
+	sessionID := uuid.NewString()
+	sessions.SetWithTTL(sessionID, idToken.Subject, time.Hour)
+	http.SetCookie(w, &http.Cookie{
+		Name:     cookieNameSession,
+		Value:    sessionID,
+		Path:     "/",
+		MaxAge:   int(time.Hour.Seconds()),
+		SameSite: http.SameSiteStrictMode,
+	})
+}

security/oidc_test.go

@@ -0,0 +1,70 @@
+package security
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/coreos/go-oidc/v3/oidc"
+)
+
+func TestOIDCConfig_isValid(t *testing.T) {
+	c := &OIDCConfig{
+		IssuerURL:       "https://sso.gatus.io/",
+		RedirectURL:     "http://localhost:80/authorization-code/callback",
+		ClientID:        "client-id",
+		ClientSecret:    "client-secret",
+		Scopes:          []string{"openid"},
+		AllowedSubjects: []string{"user1@example.com"},
+	}
+	if !c.isValid() {
+		t.Error("OIDCConfig should be valid")
+	}
+}
+
+func TestOIDCConfig_callbackHandler(t *testing.T) {
+	c := &OIDCConfig{
+		IssuerURL:       "https://sso.gatus.io/",
+		RedirectURL:     "http://localhost:80/authorization-code/callback",
+		ClientID:        "client-id",
+		ClientSecret:    "client-secret",
+		Scopes:          []string{"openid"},
+		AllowedSubjects: []string{"user1@example.com"},
+	}
+	if err := c.initialize(); err != nil {
+		t.Fatal("expected no error, but got", err)
+	}
+	// Try with no state cookie
+	request, _ := http.NewRequest("GET", "/authorization-code/callback", nil)
+	responseRecorder := httptest.NewRecorder()
+	c.callbackHandler(responseRecorder, request)
+	if responseRecorder.Code != http.StatusBadRequest {
+		t.Error("expected code to be 400, but was", responseRecorder.Code)
+	}
+	// Try with state cookie
+	request, _ = http.NewRequest("GET", "/authorization-code/callback", nil)
+	request.AddCookie(&http.Cookie{Name: cookieNameState, Value: "fake-state"})
+	responseRecorder = httptest.NewRecorder()
+	c.callbackHandler(responseRecorder, request)
+	if responseRecorder.Code != http.StatusBadRequest {
+		t.Error("expected code to be 400, but was", responseRecorder.Code)
+	}
+	// Try with state cookie and state query parameter
+	request, _ = http.NewRequest("GET", "/authorization-code/callback?state=fake-state", nil)
+	request.AddCookie(&http.Cookie{Name: cookieNameState, Value: "fake-state"})
+	responseRecorder = httptest.NewRecorder()
+	c.callbackHandler(responseRecorder, request)
+	// Exchange should fail, so 500.
+	if responseRecorder.Code != http.StatusInternalServerError {
+		t.Error("expected code to be 500, but was", responseRecorder.Code)
+	}
+}
+
+func TestOIDCConfig_setSessionCookie(t *testing.T) {
+	c := &OIDCConfig{}
+	responseRecorder := httptest.NewRecorder()
+	c.setSessionCookie(responseRecorder, &oidc.IDToken{Subject: "test@example.com"})
+	if len(responseRecorder.Result().Cookies()) == 0 {
+		t.Error("expected cookie to be set")
+	}
+}

security/sessions.go

@@ -0,0 +1,5 @@
+package security
+
+import "github.com/TwiN/gocache/v2"
+
+var sessions = gocache.NewCache().WithEvictionPolicy(gocache.LeastRecentlyUsed) // TODO: Move this to storage

security/sha512.go

@@ -6,6 +6,7 @@ import (
 )
 
 // Sha512 hashes a provided string using SHA512 and returns the resulting hash as a string
+// Deprecated: Use bcrypt instead
 func Sha512(s string) string {
 	hash := sha512.New()
 	hash.Write([]byte(s))

storage/config.go

@@ -6,8 +6,8 @@ import (
 )
 
 var (
-	ErrSQLStorageRequiresFile          = errors.New("sql storage requires a non-empty file to be defined")
-	ErrMemoryStorageDoesNotSupportFile = errors.New("memory storage does not support persistence, use sqlite if you want persistence on file")
+	ErrSQLStorageRequiresPath          = errors.New("sql storage requires a non-empty path to be defined")
+	ErrMemoryStorageDoesNotSupportPath = errors.New("memory storage does not support persistence, use sqlite if you want persistence on file")
 	ErrCannotSetBothFileAndPath        = errors.New("file has been deprecated in favor of path: you cannot set both of them")
 )
 
@@ -16,8 +16,6 @@ type Config struct {
 	// Path is the path used by the store to achieve persistence
 	// If blank, persistence is disabled.
 	// Note that not all Type support persistence
-	//
-	// XXX: Rename to path for v4.0.0
 	Path string `yaml:"path"`
 
 	// File is the path of the file to use for persistence
@@ -45,7 +43,7 @@ func (c *Config) ValidateAndSetDefaults() error {
 		c.Type = TypeMemory
 	}
 	if (c.Type == TypePostgres || c.Type == TypeSQLite) && len(c.Path) == 0 {
-		return ErrSQLStorageRequiresFile
+		return ErrSQLStorageRequiresPath
 	}
 	if c.Type == TypeMemory && len(c.Path) > 0 {
 		log.Println("WARNING: Your configuration is using a storage of type memory with persistence, which has been deprecated")
@@ -53,7 +51,7 @@ func (c *Config) ValidateAndSetDefaults() error {
 		log.Println("WARNING: If you want persistence, use 'storage.type: sqlite' instead of 'storage.type: memory'")
 		log.Println("WARNING: See https://github.com/TwiN/gatus/issues/198")
 		// XXX: Uncomment the following line for v4.0.0
-		//return ErrMemoryStorageDoesNotSupportFile
+		//return ErrMemoryStorageDoesNotSupportPath
 	}
 	return nil
 }

storage/store/memory/memory.go

@@ -3,8 +3,8 @@ package memory
 import (
 	"encoding/gob"
 	"io/fs"
-	"io/ioutil"
 	"log"
+	"os"
 	"sort"
 	"strings"
 	"sync"
@@ -51,12 +51,12 @@ func NewStore(file string) (*Store, error) {
 		_, err := store.cache.ReadFromFile(file)
 		if err != nil {
 			// XXX: Remove the block below in v4.0.0
-			if data, err2 := ioutil.ReadFile(file); err2 == nil {
+			if data, err2 := os.ReadFile(file); err2 == nil {
 				isFromOldVersion := strings.Contains(string(data), "*core.ServiceStatus")
 				if isFromOldVersion {
 					log.Println("WARNING: Couldn't read file due to recent change in v3.3.0, see https://github.com/TwiN/gatus/issues/191")
 					log.Println("WARNING: Will automatically rename old file to " + file + ".old and overwrite the current file")
-					if err = ioutil.WriteFile(file+".old", data, fs.ModePerm); err != nil {
+					if err = os.WriteFile(file+".old", data, fs.ModePerm); err != nil {
 						log.Println("WARNING: Tried my best to keep the old file, but it wasn't enough. Sorry, your file will be overwritten :(")
 					}
 					// Return the store regardless of whether there was an error or not

storage/store/sql/sql.go

@@ -493,12 +493,6 @@ func (s *Store) getEndpointStatusByKey(tx *sql.Tx, key string, parameters *pagin
 			log.Printf("[sql][getEndpointStatusByKey] Failed to retrieve results for key=%s: %s", key, err.Error())
 		}
 	}
-	//if parameters.IncludeUptime {
-	//	now := time.Now()
-	//	endpointStatus.Uptime.LastHour, _, err = s.getEndpointUptime(tx, endpointID, now.Add(-time.Hour), now)
-	//	endpointStatus.Uptime.LastTwentyFourHours, _, err = s.getEndpointUptime(tx, endpointID, now.Add(-24*time.Hour), now)
-	//	endpointStatus.Uptime.LastSevenDays, _, err = s.getEndpointUptime(tx, endpointID, now.Add(-7*24*time.Hour), now)
-	//}
 	return endpointStatus, nil
 }
 
@@ -574,6 +568,10 @@ func (s *Store) getEndpointResultsByEndpointID(tx *sql.Tx, endpointID int64, pag
 		results = append([]*core.Result{result}, results...)
 		idResultMap[id] = result
 	}
+	if len(idResultMap) == 0 {
+		// If there's no result, we'll just return an empty/nil slice
+		return
+	}
 	// Get condition results
 	args := make([]interface{}, 0, len(idResultMap))
 	query := `SELECT endpoint_result_id, condition, success

storage/store/store.go

@@ -74,6 +74,7 @@ var (
 
 func Get() Store {
 	if !initialized {
+		// This only happens in tests
 		log.Println("[store][Get] Provider requested before it was initialized, automatically initializing")
 		err := Initialize(nil)
 		if err != nil {
@@ -92,12 +93,12 @@ func Initialize(cfg *storage.Config) error {
 		cancelFunc()
 	}
 	if cfg == nil {
+		// This only happens in tests
+		log.Println("[store][Initialize] nil storage config passed as parameter. This should only happen in tests. Defaulting to an empty config.")
 		cfg = &storage.Config{}
 	}
 	if len(cfg.Path) == 0 && cfg.Type != storage.TypePostgres {
-		log.Printf("[store][Initialize] Creating storage provider with type=%s and file=%s", cfg.Type, cfg.Path)
-	} else {
-		log.Printf("[store][Initialize] Creating storage provider with type=%s", cfg.Type)
+		log.Printf("[store][Initialize] Creating storage provider of type=%s", cfg.Type)
 	}
 	ctx, cancelFunc = context.WithCancel(context.Background())
 	switch cfg.Type {

storage/store/store_test.go

@@ -184,13 +184,10 @@ func TestStore_GetEndpointStatusForMissingStatusReturnsNil(t *testing.T) {
 func TestStore_GetAllEndpointStatuses(t *testing.T) {
 	scenarios := initStoresAndBaseScenarios(t, "TestStore_GetAllEndpointStatuses")
 	defer cleanUp(scenarios)
-	firstResult := testSuccessfulResult
-	secondResult := testUnsuccessfulResult
 	for _, scenario := range scenarios {
 		t.Run(scenario.Name, func(t *testing.T) {
-			scenario.Store.Insert(&testEndpoint, &firstResult)
-			scenario.Store.Insert(&testEndpoint, &secondResult)
-			// Can't be bothered dealing with timezone issues on the worker that runs the automated tests
+			scenario.Store.Insert(&testEndpoint, &testSuccessfulResult)
+			scenario.Store.Insert(&testEndpoint, &testUnsuccessfulResult)
 			endpointStatuses, err := scenario.Store.GetAllEndpointStatuses(paging.NewEndpointStatusParams().WithResults(1, 20))
 			if err != nil {
 				t.Error("shouldn't have returned an error, got", err.Error())
@@ -210,6 +207,37 @@ func TestStore_GetAllEndpointStatuses(t *testing.T) {
 			}
 			scenario.Store.Clear()
 		})
+		t.Run(scenario.Name+"-page-2", func(t *testing.T) {
+			otherEndpoint := testEndpoint
+			otherEndpoint.Name = testEndpoint.Name + "-other"
+			scenario.Store.Insert(&testEndpoint, &testSuccessfulResult)
+			scenario.Store.Insert(&otherEndpoint, &testSuccessfulResult)
+			scenario.Store.Insert(&otherEndpoint, &testSuccessfulResult)
+			scenario.Store.Insert(&otherEndpoint, &testSuccessfulResult)
+			endpointStatuses, err := scenario.Store.GetAllEndpointStatuses(paging.NewEndpointStatusParams().WithResults(2, 2))
+			if err != nil {
+				t.Error("shouldn't have returned an error, got", err.Error())
+			}
+			if len(endpointStatuses) != 2 {
+				t.Fatal("expected 2 endpoint statuses")
+			}
+			if endpointStatuses[0] == nil || endpointStatuses[1] == nil {
+				t.Fatal("expected endpoint status to exist")
+			}
+			if len(endpointStatuses[0].Results) != 0 {
+				t.Error("expected 0 results on the first endpoint, got", len(endpointStatuses[0].Results))
+			}
+			if len(endpointStatuses[1].Results) != 1 {
+				t.Error("expected 1 result on the second endpoint, got", len(endpointStatuses[1].Results))
+			}
+			if len(endpointStatuses[0].Events) != 0 {
+				t.Error("expected 0 events on the first endpoint, got", len(endpointStatuses[0].Events))
+			}
+			if len(endpointStatuses[1].Events) != 0 {
+				t.Error("expected 0 events on the second endpoint, got", len(endpointStatuses[1].Events))
+			}
+			scenario.Store.Clear()
+		})
 	}
 }
 

test/mock.go

@@ -0,0 +1,9 @@
+package test
+
+import "net/http"
+
+type MockRoundTripper func(r *http.Request) *http.Response
+
+func (f MockRoundTripper) RoundTrip(r *http.Request) (*http.Response, error) {
+	return f(r), nil
+}

util/key.go

@@ -3,8 +3,8 @@ package util
 import "strings"
 
 // ConvertGroupAndEndpointNameToKey converts a group and an endpoint to a key
-func ConvertGroupAndEndpointNameToKey(group, endpoint string) string {
-	return sanitize(group) + "_" + sanitize(endpoint)
+func ConvertGroupAndEndpointNameToKey(groupName, endpointName string) string {
+	return sanitize(groupName) + "_" + sanitize(endpointName)
 }
 
 func sanitize(s string) string {