test: Add tests for endpoint display name

Fixes #47

.dockerignore

@@ -1,4 +1,4 @@
-examples
+.examples
 Dockerfile
 .github
 .idea

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

@@ -0,0 +1,41 @@
+## Usage
+Gatus exposes Prometheus metrics at `/metrics` if the `metrics` configuration option is set to `true`.
+
+To run this example, all you need to do is execute the following command:
+```console
+docker-compose up
+```
+Once you've done the above, you should be able to access the Grafana dashboard at `http://localhost:3000`.
+
+![Gatus Grafana dashboard](../../.github/assets/grafana-dashboard.png)
+
+
+## Queries
+By default, this example has a Grafana dashboard with some panels, but for the sake of verbosity, you'll find
+a list of simple queries below. Those make use of the `key` parameter, which is a concatenation of the endpoint's
+group and name.
+
+### Success rate
+```
+sum(rate(gatus_results_total{success="true"}[30s])) by (key) / sum(rate(gatus_results_total[30s])) by (key)
+```
+
+### Response time
+```
+gatus_results_duration_seconds
+```
+
+### 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="false"}[5m])*60) by (key)
+```

.examples/docker-compose-grafana-prometheus/config/config.yaml

@@ -2,15 +2,18 @@ metrics: true
 endpoints:
   - name: website
     url: https://twin.sh/health
-    interval: 30s
+    interval: 5m
     conditions:
       - "[STATUS] == 200"
+
+  - name: example
+    url: https://example.com/
+    interval: 5m
+    conditions:
+      - "[STATUS] == 200"
+
   - name: github
     url: https://api.github.com/healthz
     interval: 5m
-    conditions:
-      - "[STATUS] == 200"
-  - name: example
-    url: https://example.com/
     conditions:
       - "[STATUS] == 200"

.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/gatus.json

@@ -0,0 +1,582 @@
+{
+  "annotations": {
+    "list": [
+      {
+        "builtIn": 1,
+        "datasource": "-- Grafana --",
+        "enable": true,
+        "hide": true,
+        "iconColor": "rgba(0, 211, 255, 1)",
+        "name": "Annotations & Alerts",
+        "type": "dashboard"
+      }
+    ]
+  },
+  "editable": true,
+  "gnetId": null,
+  "graphTooltip": 0,
+  "id": 3,
+  "links": [],
+  "panels": [
+    {
+      "cacheTimeout": null,
+      "datasource": null,
+      "description": "Number of successful results compared to the total number of results during the current interval",
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 0,
+        "y": 0
+      },
+      "id": 9,
+      "links": [],
+      "options": {
+        "fieldOptions": {
+          "calcs": [
+            "mean"
+          ],
+          "defaults": {
+            "mappings": [
+              {
+                "id": 0,
+                "op": "=",
+                "text": "N/A",
+                "type": 1,
+                "value": "null"
+              }
+            ],
+            "max": 1,
+            "min": 0,
+            "nullValueMode": "connected",
+            "thresholds": [
+              {
+                "color": "red",
+                "value": null
+              },
+              {
+                "color": "semi-dark-orange",
+                "value": 0.6
+              },
+              {
+                "color": "yellow",
+                "value": 0.8
+              },
+              {
+                "color": "dark-green",
+                "value": 0.95
+              }
+            ],
+            "unit": "percentunit"
+          },
+          "override": {},
+          "values": false
+        },
+        "orientation": "horizontal",
+        "showThresholdLabels": false,
+        "showThresholdMarkers": false
+      },
+      "pluginVersion": "6.4.4",
+      "targets": [
+        {
+          "expr": "sum(rate(gatus_results_total{success=\"true\"}[30s])) by (key) / sum(rate(gatus_results_total[30s])) by (key)",
+          "hide": false,
+          "legendFormat": "{{key}}",
+          "refId": "B"
+        }
+      ],
+      "timeFrom": null,
+      "timeShift": null,
+      "title": "Success rate",
+      "type": "gauge"
+    },
+    {
+      "aliasColors": {},
+      "bars": false,
+      "cacheTimeout": null,
+      "dashLength": 10,
+      "dashes": false,
+      "datasource": null,
+      "fill": 1,
+      "fillGradient": 0,
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 12,
+        "y": 0
+      },
+      "id": 11,
+      "legend": {
+        "avg": false,
+        "current": false,
+        "max": false,
+        "min": false,
+        "show": true,
+        "total": false,
+        "values": false
+      },
+      "lines": true,
+      "linewidth": 1,
+      "links": [],
+      "nullPointMode": "null as zero",
+      "options": {
+        "dataLinks": []
+      },
+      "percentage": false,
+      "pluginVersion": "6.4.4",
+      "pointradius": 2,
+      "points": false,
+      "renderer": "flot",
+      "seriesOverrides": [],
+      "spaceLength": 10,
+      "stack": false,
+      "steppedLine": false,
+      "targets": [
+        {
+          "expr": "gatus_results_duration_seconds",
+          "format": "time_series",
+          "instant": false,
+          "interval": "",
+          "intervalFactor": 1,
+          "legendFormat": "{{key}}",
+          "refId": "A"
+        }
+      ],
+      "thresholds": [],
+      "timeFrom": null,
+      "timeRegions": [],
+      "timeShift": null,
+      "title": "Response time",
+      "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,
+      "cacheTimeout": null,
+      "dashLength": 10,
+      "dashes": false,
+      "datasource": null,
+      "fill": 1,
+      "fillGradient": 0,
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 0,
+        "y": 8
+      },
+      "id": 10,
+      "legend": {
+        "avg": false,
+        "current": false,
+        "max": false,
+        "min": false,
+        "show": true,
+        "total": false,
+        "values": false
+      },
+      "lines": true,
+      "linewidth": 1,
+      "links": [],
+      "nullPointMode": "connected",
+      "options": {
+        "dataLinks": []
+      },
+      "percentage": false,
+      "pluginVersion": "6.4.4",
+      "pointradius": 2,
+      "points": true,
+      "renderer": "flot",
+      "seriesOverrides": [],
+      "spaceLength": 10,
+      "stack": false,
+      "steppedLine": false,
+      "targets": [
+        {
+          "expr": "sum(rate(gatus_results_total{success=\"true\"}[30s])) by (key) / sum(rate(gatus_results_total[30s])) by (key)",
+          "format": "time_series",
+          "instant": false,
+          "interval": "",
+          "intervalFactor": 1,
+          "legendFormat": "{{key}}",
+          "refId": "A"
+        }
+      ],
+      "thresholds": [],
+      "timeFrom": null,
+      "timeRegions": [],
+      "timeShift": null,
+      "title": "Success rate",
+      "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,
+      "description": "Number of results per minute",
+      "fill": 1,
+      "fillGradient": 0,
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 12,
+        "y": 8
+      },
+      "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
+      },
+      "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[5m])*60) by (key)",
+          "format": "time_series",
+          "hide": false,
+          "instant": false,
+          "interval": "30s",
+          "intervalFactor": 1,
+          "legendFormat": "{{key}}",
+          "refId": "A"
+        }
+      ],
+      "thresholds": [],
+      "timeFrom": null,
+      "timeRegions": [],
+      "timeShift": null,
+      "title": "Total 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
+      }
+    },
+    {
+      "aliasColors": {},
+      "bars": false,
+      "dashLength": 10,
+      "dashes": false,
+      "datasource": null,
+      "fill": 1,
+      "fillGradient": 0,
+      "gridPos": {
+        "h": 7,
+        "w": 12,
+        "x": 0,
+        "y": 16
+      },
+      "id": 5,
+      "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=\"true\"}[5m])*60) by (key)",
+          "instant": false,
+          "interval": "30s",
+          "legendFormat": "{{key}}",
+          "refId": "A"
+        }
+      ],
+      "thresholds": [],
+      "timeFrom": null,
+      "timeRegions": [],
+      "timeShift": null,
+      "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
+      }
+    },
+    {
+      "aliasColors": {},
+      "bars": false,
+      "dashLength": 10,
+      "dashes": false,
+      "datasource": null,
+      "fill": 1,
+      "fillGradient": 0,
+      "gridPos": {
+        "h": 7,
+        "w": 12,
+        "x": 12,
+        "y": 16
+      },
+      "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,
+        "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
+      }
+    }
+  ],
+  "refresh": "1m",
+  "schemaVersion": 20,
+  "style": "dark",
+  "tags": [],
+  "templating": {
+    "list": []
+  },
+  "time": {
+    "from": "now-1h",
+    "to": "now"
+  },
+  "timepicker": {
+    "refresh_intervals": [
+      "5s",
+      "10s",
+      "30s",
+      "1m",
+      "5m",
+      "15m",
+      "30m",
+      "1h",
+      "2h",
+      "1d"
+    ]
+  },
+  "timezone": "",
+  "title": "Gatus",
+  "uid": "KPI7Qj1Wk",
+  "version": 2
+}

.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/config/config.yaml

@@ -1,6 +1,6 @@
 storage:
   type: postgres
-  file: "postgres://username:password@postgres:5432/gatus?sslmode=disable"
+  path: "postgres://username:password@postgres:5432/gatus?sslmode=disable"
 
 endpoints:
   - name: back-end
@@ -26,7 +26,7 @@ endpoints:
       - "[STATUS] == 200"
 
   - name: example-dns-query
-    url: "8.8.8.8" # Address of the DNS server to use
+    url: "1.1.1.1" # Address of the DNS server to use
     interval: 5m
     dns:
       query-name: "example.com"

.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/config/config.yaml

@@ -1,6 +1,6 @@
 storage:
   type: sqlite
-  file: /data/data.db
+  path: /data/data.db
 
 endpoints:
   - name: back-end
@@ -26,7 +26,7 @@ endpoints:
       - "[STATUS] == 200"
 
   - name: example-dns-query
-    url: "8.8.8.8" # Address of the DNS server to use
+    url: "1.1.1.1" # Address of the DNS server to use
     interval: 5m
     dns:
       query-name: "example.com"

.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

.examples/kubernetes/gatus.yaml

@@ -9,14 +9,17 @@ data:
     endpoints:
       - name: website
         url: https://twin.sh/health
-        interval: 1m
+        interval: 5m
         conditions:
           - "[STATUS] == 200"
+          - "[BODY].status == UP"
+
       - name: github
         url: https://api.github.com/healthz
         interval: 5m
         conditions:
           - "[STATUS] == 200"
+
       - name: cat-fact
         url: "https://cat-fact.herokuapp.com/facts/random"
         interval: 5m
@@ -27,11 +30,18 @@ data:
           - "[BODY].text == pat(*cat*)"
           - "[STATUS] == pat(2*)"
           - "[CONNECTED] == true"
+
       - name: example
         url: https://example.com/
         conditions:
           - "[STATUS] == 200"
 ---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: gatus
+  namespace: kube-system
+---
 apiVersion: apps/v1
 kind: Deployment
 metadata:
@@ -41,14 +51,16 @@ spec:
   replicas: 1
   selector:
     matchLabels:
-      k8s-app: gatus
+      app: gatus
   template:
     metadata:
-      labels:
-        k8s-app: gatus
       name: gatus
       namespace: kube-system
+      labels:
+        app: gatus
     spec:
+      serviceAccountName: gatus
+      terminationGracePeriodSeconds: 5
       containers:
         - image: twinproduction/gatus
           imagePullPolicy: IfNotPresent
@@ -64,6 +76,22 @@ spec:
             requests:
               cpu: 50m
               memory: 30M
+          readinessProbe:
+            httpGet:
+              path: /health
+              port: 8080
+            initialDelaySeconds: 5
+            periodSeconds: 10
+            successThreshold: 1
+            failureThreshold: 3
+          livenessProbe:
+            httpGet:
+              path: /health
+              port: 8080
+            initialDelaySeconds: 10
+            periodSeconds: 10
+            successThreshold: 1
+            failureThreshold: 5
           volumeMounts:
             - mountPath: /config
               name: gatus-config
@@ -84,4 +112,4 @@ spec:
       protocol: TCP
       targetPort: 8080
   selector:
-    k8s-app: gatus
+    app: gatus

.github/codecov.yml

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

.github/workflows/benchmark.yml

@@ -0,0 +1,26 @@
+name: benchmark
+on:
+  workflow_dispatch:
+    inputs:
+      repository:
+        description: "Repository to checkout. Useful for benchmarking a fork. Format should be <owner>/<repository>."
+        required: true
+        default: "TwiN/gatus"
+      ref:
+        description: "Branch, tag or SHA to checkout"
+        required: true
+        default: "master"
+jobs:
+  build:
+    name: benchmark
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: 1.18
+          repository: "${{ github.event.inputs.repository }}"
+          ref: "${{ github.event.inputs.ref }}"
+      - uses: actions/checkout@v3
+      - name: Benchmark
+        run: go test -bench=. ./storage/store

.github/workflows/build.yml

@@ -10,24 +10,22 @@ on:
       - '*.md'
 jobs:
   build:
-    name: Build
+    name: build
     runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
-      - name: Set up Go
-        uses: actions/setup-go@v2
+      - uses: actions/setup-go@v3
         with:
-          go-version: 1.16
-      - name: Check out code into the Go module directory
-        uses: actions/checkout@v2
+          go-version: 1.18
+      - uses: actions/checkout@v3
       - name: Build binary to make sure it works
         run: go build -mod vendor
       - name: Test
         # We're using "sudo" because one of the tests leverages ping, which requires super-user privileges.
         # As for the 'env "PATH=$PATH" "GOROOT=$GOROOT"', we need it to use the same "go" executable that
-        # was configured by the "Set up Go 1.15" step (otherwise, it'd use sudo's "go" executable)
+        # was configured by the "Set up Go" step (otherwise, it'd use sudo's "go" executable)
         run: sudo env "PATH=$PATH" "GOROOT=$GOROOT" go test -mod vendor ./... -race -coverprofile=coverage.txt -covermode=atomic
       - name: Codecov
-        uses: codecov/codecov-action@v1.5.2
+        uses: codecov/codecov-action@v2.1.0
         with:
-          file: ./coverage.txt
+          files: ./coverage.txt

.github/workflows/publish-experimental.yml

@@ -0,0 +1,28 @@
+name: publish-experimental
+on: [workflow_dispatch]
+jobs:
+  publish-experimental:
+    name: publish-experimental
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+    steps:
+      - uses: actions/checkout@v3
+      - name: Get image repository
+        run: echo IMAGE_REPOSITORY=$(echo ${{ secrets.DOCKER_USERNAME }}/${{ github.event.repository.name }} | tr '[:upper:]' '[:lower:]') >> $GITHUB_ENV
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      - name: Login to Docker Registry
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Build and push docker image
+        uses: docker/build-push-action@v2
+        with:
+          platforms: linux/amd64
+          pull: true
+          push: true
+          tags: |
+            ${{ env.IMAGE_REPOSITORY }}:experimental

.github/workflows/publish-latest.yml

@@ -6,13 +6,12 @@ on:
     types: [completed]
 jobs:
   publish-latest:
-    name: Publish latest
+    name: publish-latest
     runs-on: ubuntu-latest
     if: ${{ github.event.workflow_run.conclusion == 'success' }}
-    timeout-minutes: 30
+    timeout-minutes: 60
     steps:
-      - name: Check out code
-        uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - name: Get image repository
         run: echo IMAGE_REPOSITORY=$(echo ${{ secrets.DOCKER_USERNAME }}/${{ github.event.repository.name }} | tr '[:upper:]' '[:lower:]') >> $GITHUB_ENV
       - name: Set up QEMU
@@ -20,14 +19,14 @@ jobs:
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v1
       - name: Login to Docker Registry
-        uses: docker/login-action@v1
+        uses: docker/login-action@v2
         with:
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
       - 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

@@ -4,12 +4,11 @@ on:
     types: [published]
 jobs:
   publish-release:
-    name: Publish release
+    name: publish-release
     runs-on: ubuntu-latest
-    timeout-minutes: 30
+    timeout-minutes: 60
     steps:
-      - name: Check out code
-        uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - name: Get image repository
         run: echo IMAGE_REPOSITORY=$(echo ${{ secrets.DOCKER_USERNAME }}/${{ github.event.repository.name }} | tr '[:upper:]' '[:lower:]') >> $GITHUB_ENV
       - name: Get the release
@@ -19,15 +18,14 @@ jobs:
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v1
       - name: Login to Docker Registry
-        uses: docker/login-action@v1
+        uses: docker/login-action@v2
         with:
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
       - name: Build and push docker image
-        uses: docker/build-push-action@v2
+        uses: docker/build-push-action@v3
         with:
           platforms: linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64
           pull: true
           push: true
-          tags: |
-            ${{ env.IMAGE_REPOSITORY }}:${{ env.RELEASE }}
+          tags: ${{ env.IMAGE_REPOSITORY }}:${{ env.RELEASE }},${{ env.IMAGE_REPOSITORY }}:stable

.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

Dockerfile

@@ -13,7 +13,6 @@ RUN CGO_ENABLED=0 GOOS=linux go build -mod vendor -a -installsuffix cgo -o gatus
 FROM scratch
 COPY --from=builder /app/gatus .
 COPY --from=builder /app/config.yaml ./config/config.yaml
-COPY --from=builder /app/web/static ./web/static
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
 ENV PORT=8080
 EXPOSE ${PORT}

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
+
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+
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+
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+      direction or management of such entity, whether by contract or
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
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+      of this License, Derivative Works shall not include works that remain
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+          notices within Derivative Works that You distribute, alongside
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+      may provide additional or different license terms and conditions
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+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
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+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
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+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   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
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
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+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+

LICENSE.md

@@ -1,9 +0,0 @@
-MIT License
-
-Copyright (c) 2021 TwiN
-
-Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Makefile

@@ -1,5 +1,8 @@
 BINARY=gatus
 
+# Because there's a folder called "test", we need to make the target "test" phony
+.PHONY: test
+
 install:
 	go build -mod vendor -o $(BINARY) .
 
@@ -10,7 +13,7 @@ clean:
 	rm $(BINARY)
 
 test:
-	sudo go test ./alerting/... ./client/... ./config/... ./controller/... ./core/... ./jsonpath/... ./pattern/... ./security/... ./storage/... ./util/... ./watchdog/... -cover
+	go test ./... -cover
 
 
 ##########

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

@@ -11,12 +11,27 @@ 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"
+
+	// TypeMatrix is the Type for the matrix alerting provider
+	TypeMatrix Type = "matrix"
+
 	// TypeMattermost is the Type for the mattermost alerting provider
 	TypeMattermost Type = "mattermost"
 
 	// TypeMessagebird is the Type for the messagebird alerting provider
 	TypeMessagebird Type = "messagebird"
 
+	// TypeNtfy is the Type for the ntfy alerting provider
+	TypeNtfy Type = "ntfy"
+
+	// TypeOpsgenie is the Type for the opsgenie alerting provider
+	TypeOpsgenie Type = "opsgenie"
+
 	// TypePagerDuty is the Type for the pagerduty alerting provider
 	TypePagerDuty Type = "pagerduty"
 

alerting/config.go

@@ -1,47 +1,67 @@
 package alerting
 
 import (
-	"github.com/TwiN/gatus/v3/alerting/alert"
-	"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/mattermost"
-	"github.com/TwiN/gatus/v3/alerting/provider/messagebird"
-	"github.com/TwiN/gatus/v3/alerting/provider/pagerduty"
-	"github.com/TwiN/gatus/v3/alerting/provider/slack"
-	"github.com/TwiN/gatus/v3/alerting/provider/teams"
-	"github.com/TwiN/gatus/v3/alerting/provider/telegram"
-	"github.com/TwiN/gatus/v3/alerting/provider/twilio"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/alerting/provider"
+	"github.com/TwiN/gatus/v4/alerting/provider/custom"
+	"github.com/TwiN/gatus/v4/alerting/provider/discord"
+	"github.com/TwiN/gatus/v4/alerting/provider/email"
+	"github.com/TwiN/gatus/v4/alerting/provider/googlechat"
+	"github.com/TwiN/gatus/v4/alerting/provider/matrix"
+	"github.com/TwiN/gatus/v4/alerting/provider/mattermost"
+	"github.com/TwiN/gatus/v4/alerting/provider/messagebird"
+	"github.com/TwiN/gatus/v4/alerting/provider/ntfy"
+	"github.com/TwiN/gatus/v4/alerting/provider/opsgenie"
+	"github.com/TwiN/gatus/v4/alerting/provider/pagerduty"
+	"github.com/TwiN/gatus/v4/alerting/provider/slack"
+	"github.com/TwiN/gatus/v4/alerting/provider/teams"
+	"github.com/TwiN/gatus/v4/alerting/provider/telegram"
+	"github.com/TwiN/gatus/v4/alerting/provider/twilio"
 )
 
 // 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"`
+
+	// Matrix is the configuration for the matrix alerting provider
+	Matrix *matrix.AlertProvider `yaml:"matrix,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"`
+
+	// Ntfy is the configuration for the ntfy alerting provider
+	Ntfy *ntfy.AlertProvider `yaml:"ntfy,omitempty"`
+
+	// Opsgenie is the configuration for the opsgenie alerting provider
+	Opsgenie *opsgenie.AlertProvider `yaml:"opsgenie,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"`
 }
 
 // GetAlertingProviderByAlertType returns an provider.AlertProvider by its corresponding alert.Type
@@ -59,6 +79,24 @@ func (config Config) GetAlertingProviderByAlertType(alertType alert.Type) provid
 			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.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.TypeMatrix:
+		if config.Matrix == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Matrix
 	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 +109,18 @@ func (config Config) GetAlertingProviderByAlertType(alertType alert.Type) provid
 			return nil
 		}
 		return config.Messagebird
+	case alert.TypeNtfy:
+		if config.Ntfy == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Ntfy
+	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

@@ -2,16 +2,14 @@ package custom
 
 import (
 	"bytes"
-	"errors"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
-	"os"
 	"strings"
 
-	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/client"
-	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 // AlertProvider is the configuration necessary for sending an alert using a custom HTTP request
@@ -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"
@@ -57,75 +50,45 @@ func (provider *AlertProvider) GetAlertStatePlaceholderValue(resolved bool) stri
 	return status
 }
 
-func (provider *AlertProvider) buildHTTPRequest(endpointName, alertDescription string, resolved bool) *http.Request {
-	body := provider.Body
-	providerURL := provider.URL
-	method := provider.Method
-
-	if strings.Contains(body, "[ALERT_DESCRIPTION]") {
-		body = strings.ReplaceAll(body, "[ALERT_DESCRIPTION]", alertDescription)
-	}
-	if strings.Contains(body, "[SERVICE_NAME]") { // XXX: Remove this in v4.0.0
-		body = strings.ReplaceAll(body, "[SERVICE_NAME]", endpointName)
-	}
-	if strings.Contains(body, "[ENDPOINT_NAME]") {
-		body = strings.ReplaceAll(body, "[ENDPOINT_NAME]", endpointName)
-	}
-	if strings.Contains(body, "[ALERT_TRIGGERED_OR_RESOLVED]") {
-		if resolved {
-			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(true))
-		} else {
-			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(false))
-		}
-	}
-	if strings.Contains(providerURL, "[ALERT_DESCRIPTION]") {
-		providerURL = strings.ReplaceAll(providerURL, "[ALERT_DESCRIPTION]", alertDescription)
-	}
-	if strings.Contains(providerURL, "[SERVICE_NAME]") { // XXX: Remove this in v4.0.0
-		providerURL = strings.ReplaceAll(providerURL, "[SERVICE_NAME]", endpointName)
-	}
-	if strings.Contains(providerURL, "[ENDPOINT_NAME]") {
-		providerURL = strings.ReplaceAll(providerURL, "[ENDPOINT_NAME]", endpointName)
-	}
-	if strings.Contains(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]") {
-		if resolved {
-			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(true))
-		} else {
-			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(false))
-		}
+func (provider *AlertProvider) buildHTTPRequest(endpoint *core.Endpoint, alert *alert.Alert, resolved bool) *http.Request {
+	body, url, method := provider.Body, provider.URL, provider.Method
+	body = strings.ReplaceAll(body, "[ALERT_DESCRIPTION]", alert.GetDescription())
+	url = strings.ReplaceAll(url, "[ALERT_DESCRIPTION]", alert.GetDescription())
+	body = strings.ReplaceAll(body, "[ENDPOINT_NAME]", endpoint.Name)
+	url = strings.ReplaceAll(url, "[ENDPOINT_NAME]", endpoint.Name)
+	body = strings.ReplaceAll(body, "[ENDPOINT_GROUP]", endpoint.Group)
+	url = strings.ReplaceAll(url, "[ENDPOINT_GROUP]", endpoint.Group)
+	body = strings.ReplaceAll(body, "[ENDPOINT_URL]", endpoint.URL)
+	url = strings.ReplaceAll(url, "[ENDPOINT_URL]", endpoint.URL)
+	if resolved {
+		body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(true))
+		url = strings.ReplaceAll(url, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(true))
+	} else {
+		body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(false))
+		url = strings.ReplaceAll(url, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(false))
 	}
 	if len(method) == 0 {
 		method = http.MethodGet
 	}
 	bodyBuffer := bytes.NewBuffer([]byte(body))
-	request, _ := http.NewRequest(method, providerURL, bodyBuffer)
+	request, _ := http.NewRequest(method, url, bodyBuffer)
 	for k, v := range provider.Headers {
 		request.Header.Set(k, v)
 	}
 	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, alert, 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

@@ -1,106 +1,212 @@
 package custom
 
 import (
-	"io/ioutil"
+	"fmt"
+	"io"
+	"net/http"
 	"testing"
 
-	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
-	invalidProvider := AlertProvider{URL: ""}
-	if invalidProvider.IsValid() {
-		t.Error("provider shouldn't have been valid")
+	t.Run("invalid-provider", func(t *testing.T) {
+		invalidProvider := AlertProvider{URL: ""}
+		if invalidProvider.IsValid() {
+			t.Error("provider shouldn't have been valid")
+		}
+	})
+	t.Run("valid-provider", func(t *testing.T) {
+		validProvider := AlertProvider{URL: "https://example.com"}
+		if validProvider.ClientConfig != nil {
+			t.Error("provider client config should have been nil prior to IsValid() being executed")
+		}
+		if !validProvider.IsValid() {
+			t.Error("provider should've been valid")
+		}
+		if validProvider.ClientConfig == nil {
+			t.Error("provider client config should have been set after IsValid() was executed")
+		}
+	})
+}
+
+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,
+		},
 	}
-	validProvider := AlertProvider{URL: "https://example.com"}
-	if !validProvider.IsValid() {
-		t.Error("provider should've been valid")
+	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"
-		ExpectedBody = "endpoint-name,alert-description,RESOLVED"
-	)
+func TestAlertProvider_buildHTTPRequest(t *testing.T) {
 	customAlertProvider := &AlertProvider{
-		URL:     "https://example.com/[ENDPOINT_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
-		Body:    "[ENDPOINT_NAME],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
-		Headers: nil,
+		URL:  "https://example.com/[ENDPOINT_GROUP]/[ENDPOINT_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]&url=[ENDPOINT_URL]",
+		Body: "[ENDPOINT_NAME],[ENDPOINT_GROUP],[ALERT_DESCRIPTION],[ENDPOINT_URL],[ALERT_TRIGGERED_OR_RESOLVED]",
 	}
-	request := customAlertProvider.buildHTTPRequest("endpoint-name", "alert-description", true)
-	if request.URL.String() != ExpectedURL {
-		t.Error("expected URL to be", ExpectedURL, "was", request.URL.String())
+	alertDescription := "alert-description"
+	scenarios := []struct {
+		AlertProvider *AlertProvider
+		Resolved      bool
+		ExpectedURL   string
+		ExpectedBody  string
+	}{
+		{
+			AlertProvider: customAlertProvider,
+			Resolved:      true,
+			ExpectedURL:   "https://example.com/endpoint-group/endpoint-name?event=RESOLVED&description=alert-description&url=https://example.com",
+			ExpectedBody:  "endpoint-name,endpoint-group,alert-description,https://example.com,RESOLVED",
+		},
+		{
+			AlertProvider: customAlertProvider,
+			Resolved:      false,
+			ExpectedURL:   "https://example.com/endpoint-group/endpoint-name?event=TRIGGERED&description=alert-description&url=https://example.com",
+			ExpectedBody:  "endpoint-name,endpoint-group,alert-description,https://example.com,TRIGGERED",
+		},
 	}
-	body, _ := ioutil.ReadAll(request.Body)
-	if string(body) != ExpectedBody {
-		t.Error("expected body to be", ExpectedBody, "was", string(body))
-	}
-}
-
-func TestAlertProvider_buildHTTPRequestWhenTriggered(t *testing.T) {
-	const (
-		ExpectedURL  = "https://example.com/endpoint-name?event=TRIGGERED&description=alert-description"
-		ExpectedBody = "endpoint-name,alert-description,TRIGGERED"
-	)
-	customAlertProvider := &AlertProvider{
-		URL:     "https://example.com/[ENDPOINT_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
-		Body:    "[ENDPOINT_NAME],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
-		Headers: map[string]string{"Authorization": "Basic hunter2"},
-	}
-	request := customAlertProvider.buildHTTPRequest("endpoint-name", "alert-description", false)
-	if request.URL.String() != ExpectedURL {
-		t.Error("expected URL to be", ExpectedURL, "was", request.URL.String())
-	}
-	body, _ := ioutil.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)
+	for _, scenario := range scenarios {
+		t.Run(fmt.Sprintf("resolved-%v-with-default-placeholders", scenario.Resolved), func(t *testing.T) {
+			request := customAlertProvider.buildHTTPRequest(
+				&core.Endpoint{Name: "endpoint-name", Group: "endpoint-group", URL: "https://example.com"},
+				&alert.Alert{Description: &alertDescription},
+				scenario.Resolved,
+			)
+			if request.URL.String() != scenario.ExpectedURL {
+				t.Error("expected URL to be", scenario.ExpectedURL, "got", request.URL.String())
+			}
+			body, _ := io.ReadAll(request.Body)
+			if string(body) != scenario.ExpectedBody {
+				t.Error("expected body to be", scenario.ExpectedBody, "got", string(body))
+			}
+		})
 	}
 }
 
 func TestAlertProvider_buildHTTPRequestWithCustomPlaceholder(t *testing.T) {
-	const (
-		ExpectedURL  = "https://example.com/endpoint-name?event=test&description=alert-description"
-		ExpectedBody = "endpoint-name,alert-description,test"
-	)
 	customAlertProvider := &AlertProvider{
-		URL:     "https://example.com/[ENDPOINT_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
-		Body:    "[ENDPOINT_NAME],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
+		URL:     "https://example.com/[ENDPOINT_GROUP]/[ENDPOINT_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
+		Body:    "[ENDPOINT_NAME],[ENDPOINT_GROUP],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
 		Headers: nil,
 		Placeholders: map[string]map[string]string{
 			"ALERT_TRIGGERED_OR_RESOLVED": {
-				"RESOLVED": "test",
+				"RESOLVED":  "fixed",
+				"TRIGGERED": "boom",
 			},
 		},
 	}
-	request := customAlertProvider.buildHTTPRequest("endpoint-name", "alert-description", true)
-	if request.URL.String() != ExpectedURL {
-		t.Error("expected URL to be", ExpectedURL, "was", request.URL.String())
+	alertDescription := "alert-description"
+	scenarios := []struct {
+		AlertProvider *AlertProvider
+		Resolved      bool
+		ExpectedURL   string
+		ExpectedBody  string
+	}{
+		{
+			AlertProvider: customAlertProvider,
+			Resolved:      true,
+			ExpectedURL:   "https://example.com/endpoint-group/endpoint-name?event=fixed&description=alert-description",
+			ExpectedBody:  "endpoint-name,endpoint-group,alert-description,fixed",
+		},
+		{
+			AlertProvider: customAlertProvider,
+			Resolved:      false,
+			ExpectedURL:   "https://example.com/endpoint-group/endpoint-name?event=boom&description=alert-description",
+			ExpectedBody:  "endpoint-name,endpoint-group,alert-description,boom",
+		},
 	}
-	body, _ := ioutil.ReadAll(request.Body)
-	if string(body) != ExpectedBody {
-		t.Error("expected body to be", ExpectedBody, "was", string(body))
+	for _, scenario := range scenarios {
+		t.Run(fmt.Sprintf("resolved-%v-with-custom-placeholders", scenario.Resolved), func(t *testing.T) {
+			request := customAlertProvider.buildHTTPRequest(
+				&core.Endpoint{Name: "endpoint-name", Group: "endpoint-group"},
+				&alert.Alert{Description: &alertDescription},
+				scenario.Resolved,
+			)
+			if request.URL.String() != scenario.ExpectedURL {
+				t.Error("expected URL to be", scenario.ExpectedURL, "got", request.URL.String())
+			}
+			body, _ := io.ReadAll(request.Body)
+			if string(body) != scenario.ExpectedBody {
+				t.Error("expected body to be", scenario.ExpectedBody, "got", string(body))
+			}
+		})
 	}
 }
 
 func TestAlertProvider_GetAlertStatePlaceholderValueDefaults(t *testing.T) {
 	customAlertProvider := &AlertProvider{
-		URL:          "https://example.com/[ENDPOINT_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
-		Body:         "[ENDPOINT_NAME],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
-		Headers:      nil,
-		Placeholders: nil,
+		URL:  "https://example.com/[ENDPOINT_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
+		Body: "[ENDPOINT_NAME],[ENDPOINT_GROUP],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
 	}
 	if customAlertProvider.GetAlertStatePlaceholderValue(true) != "RESOLVED" {
 		t.Error("expected RESOLVED, got", customAlertProvider.GetAlertStatePlaceholderValue(true))
@@ -110,25 +216,11 @@ func TestAlertProvider_GetAlertStatePlaceholderValueDefaults(t *testing.T) {
 	}
 }
 
-// TestAlertProvider_isBackwardCompatibleWithServiceRename checks if the custom alerting provider still supports
-// service placeholders after the migration from "service" to "endpoint"
-//
-// XXX: Remove this in v4.0.0
-func TestAlertProvider_isBackwardCompatibleWithServiceRename(t *testing.T) {
-	const (
-		ExpectedURL  = "https://example.com/endpoint-name?event=TRIGGERED&description=alert-description"
-		ExpectedBody = "endpoint-name,alert-description,TRIGGERED"
-	)
-	customAlertProvider := &AlertProvider{
-		URL:  "https://example.com/[SERVICE_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
-		Body: "[SERVICE_NAME],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
+func TestAlertProvider_GetDefaultAlert(t *testing.T) {
+	if (AlertProvider{DefaultAlert: &alert.Alert{}}).GetDefaultAlert() == nil {
+		t.Error("expected default alert to be not nil")
 	}
-	request := customAlertProvider.buildHTTPRequest("endpoint-name", "alert-description", false)
-	if request.URL.String() != ExpectedURL {
-		t.Error("expected URL to be", ExpectedURL, "was", request.URL.String())
-	}
-	body, _ := ioutil.ReadAll(request.Body)
-	if string(body) != ExpectedBody {
-		t.Error("expected body to be", ExpectedBody, "was", string(body))
+	if (AlertProvider{DefaultAlert: nil}).GetDefaultAlert() != nil {
+		t.Error("expected default alert to be nil")
 	}
 }

alerting/provider/discord/discord.go

@@ -1,12 +1,14 @@
 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 // AlertProvider is the configuration necessary for sending an alert using Discord
@@ -14,23 +16,60 @@ 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"`
+
+	// 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"`
+	WebhookURL string `yaml:"webhook-url"`
 }
 
 // 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.WebhookURL) == 0 {
+				return false
+			}
+			registeredGroups[override.Group] = true
+		}
+	}
 	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.getWebhookURLForGroup(endpoint.Group), 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 +85,7 @@ 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 +101,19 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
       ]
     }
   ]
-}`, message, description, colorCode, results),
-		Headers: map[string]string{"Content-Type": "application/json"},
+}`, message, description, colorCode, results)
+}
+
+// getWebhookURLForGroup returns the appropriate Webhook URL integration to for a given group
+func (provider *AlertProvider) getWebhookURLForGroup(group string) string {
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if group == override.Group {
+				return override.WebhookURL
+			}
+		}
 	}
+	return provider.WebhookURL
 }
 
 // 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -21,50 +22,237 @@ 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_IsValidWithOverride(t *testing.T) {
+	providerWithInvalidOverrideGroup := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "",
+			},
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "resolved") {
-		t.Error("customAlertProvider.Body should've contained the substring resolved")
+	if providerWithInvalidOverrideGroup.IsValid() {
+		t.Error("provider Group shouldn't have been valid")
 	}
-	if customAlertProvider.URL != "http://example.com" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
+	providerWithInvalidOverrideTo := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "",
+				Group:      "group",
+			},
+		},
 	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	if providerWithInvalidOverrideTo.IsValid() {
+		t.Error("provider integration key shouldn't have been valid")
 	}
-	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())
+	providerWithValidOverride := AlertProvider{
+		WebhookURL: "http://example.com",
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "group",
+			},
+		},
 	}
-	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"])
+	if !providerWithValidOverride.IsValid() {
+		t.Error("provider should've been valid")
 	}
 }
 
-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_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, "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) {
+			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_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}",
+		},
+	}
+	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")
+	}
+}
+
+func TestAlertProvider_getWebhookURLForGroup(t *testing.T) {
+	tests := []struct {
+		Name           string
+		Provider       AlertProvider
+		InputGroup     string
+		ExpectedOutput string
+	}{
+		{
+			Name: "provider-no-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-no-override-specify-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-group-should-override",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example01.com",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.Name, func(t *testing.T) {
+			if got := tt.Provider.getWebhookURLForGroup(tt.InputGroup); got != tt.ExpectedOutput {
+				t.Errorf("AlertProvider.getWebhookURLForGroup() = %v, want %v", got, tt.ExpectedOutput)
+			}
+		})
 	}
 }

alerting/provider/email/email.go

@@ -0,0 +1,109 @@
+package email
+
+import (
+	"fmt"
+	"math"
+	"strings"
+
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/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/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/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 +1,156 @@
+package googlechat
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/http"
+
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/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"`
+
+	// 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"`
+	WebhookURL string `yaml:"webhook-url"`
+}
+
+// IsValid returns whether the provider's configuration is valid
+func (provider *AlertProvider) IsValid() bool {
+	if provider.ClientConfig == nil {
+		provider.ClientConfig = client.GetDefaultConfig()
+	}
+
+	registeredGroups := make(map[string]bool)
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if isAlreadyRegistered := registeredGroups[override.Group]; isAlreadyRegistered || override.Group == "" || len(override.WebhookURL) == 0 {
+				return false
+			}
+			registeredGroups[override.Group] = true
+		}
+	}
+
+	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.getWebhookURLForGroup(endpoint.Group), 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)
+}
+
+// getWebhookURLForGroup returns the appropriate Webhook URL integration to for a given group
+func (provider *AlertProvider) getWebhookURLForGroup(group string) string {
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if group == override.Group {
+				return override.WebhookURL
+			}
+		}
+	}
+	return provider.WebhookURL
+}
+
+// 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 +1,260 @@
+package googlechat
+
+import (
+	"encoding/json"
+	"net/http"
+	"testing"
+
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/test"
+)
+
+func TestAlertDefaultProvider_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_IsValidWithOverride(t *testing.T) {
+	providerWithInvalidOverrideGroup := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "",
+			},
+		},
+	}
+	if providerWithInvalidOverrideGroup.IsValid() {
+		t.Error("provider Group shouldn't have been valid")
+	}
+	providerWithInvalidOverrideTo := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "",
+				Group:      "group",
+			},
+		},
+	}
+	if providerWithInvalidOverrideTo.IsValid() {
+		t.Error("provider integration key shouldn't have been valid")
+	}
+	providerWithValidOverride := AlertProvider{
+		WebhookURL: "http://example.com",
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "group",
+			},
+		},
+	}
+	if !providerWithValidOverride.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")
+	}
+}
+
+func TestAlertProvider_getWebhookURLForGroup(t *testing.T) {
+	tests := []struct {
+		Name           string
+		Provider       AlertProvider
+		InputGroup     string
+		ExpectedOutput string
+	}{
+		{
+			Name: "provider-no-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-no-override-specify-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-group-should-override",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example01.com",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.Name, func(t *testing.T) {
+			if got := tt.Provider.getWebhookURLForGroup(tt.InputGroup); got != tt.ExpectedOutput {
+				t.Errorf("AlertProvider.getToForGroup() = %v, want %v", got, tt.ExpectedOutput)
+			}
+		})
+	}
+}

alerting/provider/matrix/matrix.go

@@ -0,0 +1,183 @@
+package matrix
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"math/rand"
+	"net/http"
+	"net/url"
+	"time"
+
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+)
+
+// AlertProvider is the configuration necessary for sending an alert using Matrix
+type AlertProvider struct {
+	MatrixProviderConfig `yaml:",inline"`
+
+	// 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"`
+
+	MatrixProviderConfig `yaml:",inline"`
+}
+
+const defaultHomeserverURL = "https://matrix-client.matrix.org"
+
+type MatrixProviderConfig struct {
+	// ServerURL is the custom homeserver to use (optional)
+	ServerURL string `yaml:"server-url"`
+
+	// AccessToken is the bot user's access token to send messages
+	AccessToken string `yaml:"access-token"`
+
+	// InternalRoomID is the room that the bot user has permissions to send messages to
+	InternalRoomID string `yaml:"internal-room-id"`
+}
+
+// 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.AccessToken) == 0 || len(override.InternalRoomID) == 0 {
+				return false
+			}
+			registeredGroups[override.Group] = true
+		}
+	}
+	return len(provider.AccessToken) > 0 && len(provider.InternalRoomID) > 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)))
+	config := provider.getConfigForGroup(endpoint.Group)
+	if config.ServerURL == "" {
+		config.ServerURL = defaultHomeserverURL
+	}
+	// The Matrix endpoint requires a unique transaction ID for each event sent
+	txnId := randStringBytes(24)
+	request, err := http.NewRequest(
+		http.MethodPut,
+		fmt.Sprintf("%s/_matrix/client/v3/rooms/%s/send/m.room.message/%s?access_token=%s",
+			config.ServerURL,
+			url.PathEscape(config.InternalRoomID),
+			txnId,
+			url.QueryEscape(config.AccessToken),
+		),
+		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 {
+	return fmt.Sprintf(`{
+	"msgtype": "m.text",
+	"format": "org.matrix.custom.html",
+	"body": "%s",
+	"formatted_body": "%s"
+}`,
+		buildPlaintextMessageBody(endpoint, alert, result, resolved),
+		buildHTMLMessageBody(endpoint, alert, result, resolved),
+	)
+}
+
+// buildPlaintextMessageBody builds the message body in plaintext to include in request
+func buildPlaintextMessageBody(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 after passing successfully %d time(s) in a row", endpoint.DisplayName(), alert.SuccessThreshold)
+	} else {
+		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("\\n%s - %s", prefix, conditionResult.Condition)
+	}
+	var description string
+	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
+		description = "\\n" + alertDescription
+	}
+	return fmt.Sprintf("%s%s\\n%s", message, description, results)
+}
+
+// buildHTMLMessageBody builds the message body in HTML to include in request
+func buildHTMLMessageBody(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) string {
+	var message, results string
+	if resolved {
+		message = fmt.Sprintf("An alert for <code>%s</code> has been resolved after passing successfully %d time(s) in a row", endpoint.DisplayName(), alert.SuccessThreshold)
+	} else {
+		message = fmt.Sprintf("An alert for <code>%s</code> 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("<li>%s - <code>%s</code></li>", prefix, conditionResult.Condition)
+	}
+	var description string
+	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
+		description = fmt.Sprintf("\\n<blockquote>%s</blockquote>", alertDescription)
+	}
+	return fmt.Sprintf("<h3>%s</h3>%s\\n<h5>Condition results</h5><ul>%s</ul>", message, description, results)
+}
+
+// getConfigForGroup returns the appropriate configuration for a given group
+func (provider *AlertProvider) getConfigForGroup(group string) MatrixProviderConfig {
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if group == override.Group {
+				return override.MatrixProviderConfig
+			}
+		}
+	}
+	return provider.MatrixProviderConfig
+}
+
+func randStringBytes(n int) string {
+	// All the compatible characters to use in a transaction ID
+	const availableCharacterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+	b := make([]byte, n)
+	rand.Seed(time.Now().UnixNano())
+	for i := range b {
+		b[i] = availableCharacterBytes[rand.Intn(len(availableCharacterBytes))]
+	}
+	return string(b)
+}
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/matrix/matrix_test.go

@@ -0,0 +1,331 @@
+package matrix
+
+import (
+	"encoding/json"
+	"net/http"
+	"testing"
+
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/test"
+)
+
+func TestAlertProvider_IsValid(t *testing.T) {
+	invalidProvider := AlertProvider{
+		MatrixProviderConfig: MatrixProviderConfig{
+			AccessToken:    "",
+			InternalRoomID: "",
+		},
+	}
+	if invalidProvider.IsValid() {
+		t.Error("provider shouldn't have been valid")
+	}
+	validProvider := AlertProvider{
+		MatrixProviderConfig: MatrixProviderConfig{
+			AccessToken:    "1",
+			InternalRoomID: "!a:example.com",
+		},
+	}
+	if !validProvider.IsValid() {
+		t.Error("provider should've been valid")
+	}
+	validProviderWithHomeserver := AlertProvider{
+		MatrixProviderConfig: MatrixProviderConfig{
+			ServerURL:      "https://example.com",
+			AccessToken:    "1",
+			InternalRoomID: "!a:example.com",
+		},
+	}
+	if !validProviderWithHomeserver.IsValid() {
+		t.Error("provider with homeserver should've been valid")
+	}
+}
+
+func TestAlertProvider_IsValidWithOverride(t *testing.T) {
+	providerWithInvalidOverrideGroup := AlertProvider{
+		Overrides: []Override{
+			{
+				Group: "",
+				MatrixProviderConfig: MatrixProviderConfig{
+					AccessToken:    "",
+					InternalRoomID: "",
+				},
+			},
+		},
+	}
+	if providerWithInvalidOverrideGroup.IsValid() {
+		t.Error("provider Group shouldn't have been valid")
+	}
+	providerWithInvalidOverrideTo := AlertProvider{
+		Overrides: []Override{
+			{
+				Group: "group",
+				MatrixProviderConfig: MatrixProviderConfig{
+					AccessToken:    "",
+					InternalRoomID: "",
+				},
+			},
+		},
+	}
+	if providerWithInvalidOverrideTo.IsValid() {
+		t.Error("provider integration key shouldn't have been valid")
+	}
+	providerWithValidOverride := AlertProvider{
+		MatrixProviderConfig: MatrixProviderConfig{
+			AccessToken:    "1",
+			InternalRoomID: "!a:example.com",
+		},
+		Overrides: []Override{
+			{
+				Group: "group",
+				MatrixProviderConfig: MatrixProviderConfig{
+					ServerURL:      "https://example.com",
+					AccessToken:    "1",
+					InternalRoomID: "!a:example.com",
+				},
+			},
+		},
+	}
+	if !providerWithValidOverride.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"},
+				&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\t\"msgtype\": \"m.text\",\n\t\"format\": \"org.matrix.custom.html\",\n\t\"body\": \"An alert for `endpoint-name` has been triggered due to having failed 3 time(s) in a row\\ndescription-1\\n\\n✕ - [CONNECTED] == true\\n✕ - [STATUS] == 200\",\n\t\"formatted_body\": \"<h3>An alert for <code>endpoint-name</code> has been triggered due to having failed 3 time(s) in a row</h3>\\n<blockquote>description-1</blockquote>\\n<h5>Condition results</h5><ul><li>❌ - <code>[CONNECTED] == true</code></li><li>❌ - <code>[STATUS] == 200</code></li></ul>\"\n}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\n\t\"msgtype\": \"m.text\",\n\t\"format\": \"org.matrix.custom.html\",\n\t\"body\": \"An alert for `endpoint-name` has been resolved after passing successfully 5 time(s) in a row\\ndescription-2\\n\\n✓ - [CONNECTED] == true\\n✓ - [STATUS] == 200\",\n\t\"formatted_body\": \"<h3>An alert for <code>endpoint-name</code> has been resolved after passing successfully 5 time(s) in a row</h3>\\n<blockquote>description-2</blockquote>\\n<h5>Condition results</h5><ul><li>✅ - <code>[CONNECTED] == true</code></li><li>✅ - <code>[STATUS] == 200</code></li></ul>\"\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,
+			)
+			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")
+	}
+}
+
+func TestAlertProvider_getConfigForGroup(t *testing.T) {
+	tests := []struct {
+		Name           string
+		Provider       AlertProvider
+		InputGroup     string
+		ExpectedOutput MatrixProviderConfig
+	}{
+		{
+			Name: "provider-no-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				MatrixProviderConfig: MatrixProviderConfig{
+					ServerURL:      "https://example.com",
+					AccessToken:    "1",
+					InternalRoomID: "!a:example.com",
+				},
+				Overrides: nil,
+			},
+			InputGroup: "",
+			ExpectedOutput: MatrixProviderConfig{
+				ServerURL:      "https://example.com",
+				AccessToken:    "1",
+				InternalRoomID: "!a:example.com",
+			},
+		},
+		{
+			Name: "provider-no-override-specify-group-should-default",
+			Provider: AlertProvider{
+				MatrixProviderConfig: MatrixProviderConfig{
+					ServerURL:      "https://example.com",
+					AccessToken:    "1",
+					InternalRoomID: "!a:example.com",
+				},
+				Overrides: nil,
+			},
+			InputGroup: "group",
+			ExpectedOutput: MatrixProviderConfig{
+				ServerURL:      "https://example.com",
+				AccessToken:    "1",
+				InternalRoomID: "!a:example.com",
+			},
+		},
+		{
+			Name: "provider-with-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				MatrixProviderConfig: MatrixProviderConfig{
+					ServerURL:      "https://example.com",
+					AccessToken:    "1",
+					InternalRoomID: "!a:example.com",
+				},
+				Overrides: []Override{
+					{
+						Group: "group",
+						MatrixProviderConfig: MatrixProviderConfig{
+							ServerURL:      "https://example01.com",
+							AccessToken:    "12",
+							InternalRoomID: "!a:example01.com",
+						},
+					},
+				},
+			},
+			InputGroup: "",
+			ExpectedOutput: MatrixProviderConfig{
+				ServerURL:      "https://example.com",
+				AccessToken:    "1",
+				InternalRoomID: "!a:example.com",
+			},
+		},
+		{
+			Name: "provider-with-override-specify-group-should-override",
+			Provider: AlertProvider{
+				MatrixProviderConfig: MatrixProviderConfig{
+					ServerURL:      "https://example.com",
+					AccessToken:    "1",
+					InternalRoomID: "!a:example.com",
+				},
+				Overrides: []Override{
+					{
+						Group: "group",
+						MatrixProviderConfig: MatrixProviderConfig{
+							ServerURL:      "https://example01.com",
+							AccessToken:    "12",
+							InternalRoomID: "!a:example01.com",
+						},
+					},
+				},
+			},
+			InputGroup: "group",
+			ExpectedOutput: MatrixProviderConfig{
+				ServerURL:      "https://example01.com",
+				AccessToken:    "12",
+				InternalRoomID: "!a:example01.com",
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.Name, func(t *testing.T) {
+			if got := tt.Provider.getConfigForGroup(tt.InputGroup); got != tt.ExpectedOutput {
+				t.Errorf("AlertProvider.getConfigForGroup() = %v, want %v", got, tt.ExpectedOutput)
+			}
+		})
+	}
+}

alerting/provider/mattermost/mattermost.go

@@ -1,13 +1,14 @@
 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"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 // AlertProvider is the configuration necessary for sending an alert using Mattermost
@@ -15,10 +16,19 @@ 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"`
+
+	// 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"`
+	WebhookURL string `yaml:"webhook-url"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -26,18 +36,45 @@ func (provider *AlertProvider) IsValid() bool {
 	if provider.ClientConfig == nil {
 		provider.ClientConfig = client.GetDefaultConfig()
 	}
+	if provider.Overrides != nil {
+		registeredGroups := make(map[string]bool)
+		for _, override := range provider.Overrides {
+			if isAlreadyRegistered := registeredGroups[override.Group]; isAlreadyRegistered || override.Group == "" || len(override.WebhookURL) == 0 {
+				return false
+			}
+			registeredGroups[override.Group] = true
+		}
+	}
 	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.getWebhookURLForGroup(endpoint.Group), 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 +91,10 @@ 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 +116,19 @@ 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)
+}
+
+// getWebhookURLForGroup returns the appropriate Webhook URL integration to for a given group
+func (provider *AlertProvider) getWebhookURLForGroup(group string) string {
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if group == override.Group {
+				return override.WebhookURL
+			}
+		}
 	}
+	return provider.WebhookURL
 }
 
 // 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -21,50 +22,241 @@ 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_IsValidWithOverride(t *testing.T) {
+	providerWithInvalidOverrideGroup := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "",
+			},
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "resolved") {
-		t.Error("customAlertProvider.Body should've contained the substring resolved")
+
+	if providerWithInvalidOverrideGroup.IsValid() {
+		t.Error("provider Group shouldn't have been valid")
 	}
-	if customAlertProvider.URL != "http://example.org" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
+
+	providerWithInvalidOverrideWebHookUrl := AlertProvider{
+		Overrides: []Override{
+			{
+
+				WebhookURL: "",
+				Group:      "group",
+			},
+		},
 	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	if providerWithInvalidOverrideWebHookUrl.IsValid() {
+		t.Error("provider WebHookURL shoudn't have been valid")
 	}
-	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())
+
+	providerWithValidOverride := AlertProvider{
+		WebhookURL: "http://example.com",
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "group",
+			},
+		},
 	}
-	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"])
+	if !providerWithValidOverride.IsValid() {
+		t.Error("provider should've been valid")
 	}
 }
 
-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_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, "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) {
+			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_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}",
+		},
+	}
+	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")
+	}
+}
+
+func TestAlertProvider_getWebhookURLForGroup(t *testing.T) {
+	tests := []struct {
+		Name           string
+		Provider       AlertProvider
+		InputGroup     string
+		ExpectedOutput string
+	}{
+		{
+			Name: "provider-no-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-no-override-specify-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-group-should-override",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example01.com",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.Name, func(t *testing.T) {
+			if got := tt.Provider.getWebhookURLForGroup(tt.InputGroup); got != tt.ExpectedOutput {
+				t.Errorf("AlertProvider.getToForGroup() = %v, want %v", got, tt.ExpectedOutput)
+			}
+		})
 	}
 }

alerting/provider/messagebird/messagebird.go

@@ -1,12 +1,14 @@
 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 const (
@@ -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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/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/ntfy/ntfy.go

@@ -0,0 +1,84 @@
+package ntfy
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/http"
+
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+)
+
+const (
+	DefaultURL      = "https://ntfy.sh"
+	DefaultPriority = 3
+)
+
+// AlertProvider is the configuration necessary for sending an alert using Slack
+type AlertProvider struct {
+	Topic    string `yaml:"topic"`
+	URL      string `yaml:"url,omitempty"`      // Defaults to DefaultURL
+	Priority int    `yaml:"priority,omitempty"` // Defaults to DefaultPriority
+
+	// 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 len(provider.URL) == 0 {
+		provider.URL = DefaultURL
+	}
+	if provider.Priority == 0 {
+		provider.Priority = DefaultPriority
+	}
+	return len(provider.URL) > 0 && len(provider.Topic) > 0 && provider.Priority > 0 && provider.Priority < 6
+}
+
+// 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.URL, 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, tag string
+	if len(alert.GetDescription()) > 0 {
+		message = endpoint.DisplayName() + " - " + alert.GetDescription()
+	} else {
+		message = endpoint.DisplayName()
+	}
+	if resolved {
+		tag = "white_check_mark"
+	} else {
+		tag = "x"
+	}
+	return fmt.Sprintf(`{
+  "topic": "%s",
+  "title": "Gatus",
+  "message": "%s",
+  "tags": ["%s"],
+  "priority": %d
+}`, provider.Topic, message, tag, provider.Priority)
+}
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/ntfy/ntfy_test.go

@@ -0,0 +1,104 @@
+package ntfy
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/core"
+)
+
+func TestAlertDefaultProvider_IsValid(t *testing.T) {
+	scenarios := []struct {
+		name     string
+		provider AlertProvider
+		expected bool
+	}{
+		{
+			name:     "valid",
+			provider: AlertProvider{URL: "https://ntfy.sh", Topic: "example", Priority: 1},
+			expected: true,
+		},
+		{
+			name:     "no-url-should-use-default-value",
+			provider: AlertProvider{Topic: "example", Priority: 1},
+			expected: true,
+		},
+		{
+			name:     "invalid-topic",
+			provider: AlertProvider{URL: "https://ntfy.sh", Topic: "", Priority: 1},
+			expected: false,
+		},
+		{
+			name:     "invalid-priority-too-high",
+			provider: AlertProvider{URL: "https://ntfy.sh", Topic: "example", Priority: 6},
+			expected: false,
+		},
+		{
+			name:     "invalid-priority-too-low",
+			provider: AlertProvider{URL: "https://ntfy.sh", Topic: "example", Priority: -1},
+			expected: false,
+		},
+		{
+			name:     "no-priority-should-use-default-value",
+			provider: AlertProvider{URL: "https://ntfy.sh", Topic: "example"},
+			expected: true,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.name, func(t *testing.T) {
+			if scenario.provider.IsValid() != scenario.expected {
+				t.Errorf("expected %t, got %t", scenario.expected, scenario.provider.IsValid())
+			}
+		})
+	}
+}
+
+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{URL: "https://ntfy.sh", Topic: "example", Priority: 1},
+			Alert:        alert.Alert{Description: &firstDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     false,
+			ExpectedBody: "{\n  \"topic\": \"example\",\n  \"title\": \"Gatus\",\n  \"message\": \"endpoint-name - description-1\",\n  \"tags\": [\"x\"],\n  \"priority\": 1\n}",
+		},
+		{
+			Name:         "resolved",
+			Provider:     AlertProvider{URL: "https://ntfy.sh", Topic: "example", Priority: 2},
+			Alert:        alert.Alert{Description: &secondDescription, SuccessThreshold: 5, FailureThreshold: 3},
+			Resolved:     true,
+			ExpectedBody: "{\n  \"topic\": \"example\",\n  \"title\": \"Gatus\",\n  \"message\": \"endpoint-name - description-2\",\n  \"tags\": [\"white_check_mark\"],\n  \"priority\": 2\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,
+			)
+			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())
+			}
+		})
+	}
+}

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/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/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/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/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

@@ -1,12 +1,16 @@
 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 const (
@@ -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",
@@ -71,15 +107,11 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
     "source": "%s",
     "severity": "critical"
   }
-}`, provider.getPagerDutyIntegrationKeyForGroup(endpoint.Group), resolveKey, eventAction, message, endpoint.Name),
-		Headers: map[string]string{
-			"Content-Type": "application/json",
-		},
-	}
+}`, provider.getIntegrationKeyForGroup(endpoint.Group), resolveKey, eventAction, message, endpoint.Name)
 }
 
-// getPagerDutyIntegrationKeyForGroup returns the appropriate pagerduty integration key for a given group
-func (provider *AlertProvider) getPagerDutyIntegrationKeyForGroup(group string) string {
+// getIntegrationKeyForGroup returns the appropriate pagerduty integration key for a given group
+func (provider *AlertProvider) getIntegrationKeyForGroup(group string) string {
 	if provider.Overrides != nil {
 		for _, override := range provider.Overrides {
 			if group == override.Group {
@@ -87,13 +119,16 @@ func (provider *AlertProvider) getPagerDutyIntegrationKeyForGroup(group string)
 			}
 		}
 	}
-	if provider.IntegrationKey != "" {
-		return provider.IntegrationKey
-	}
-	return ""
+	return provider.IntegrationKey
 }
 
 // GetDefaultAlert returns the provider's default alert configuration
 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
@@ -57,111 +58,122 @@ 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())
+			}
+		})
 	}
 }
 
-func TestAlertProvider_getPagerDutyIntegrationKey(t *testing.T) {
+func TestAlertProvider_getIntegrationKeyForGroup(t *testing.T) {
 	scenarios := []struct {
 		Name           string
 		Provider       AlertProvider
@@ -217,9 +229,18 @@ func TestAlertProvider_getPagerDutyIntegrationKey(t *testing.T) {
 	}
 	for _, scenario := range scenarios {
 		t.Run(scenario.Name, func(t *testing.T) {
-			if output := scenario.Provider.getPagerDutyIntegrationKeyForGroup(scenario.InputGroup); output != scenario.ExpectedOutput {
+			if output := scenario.Provider.getIntegrationKeyForGroup(scenario.InputGroup); output != scenario.ExpectedOutput {
 				t.Errorf("expected %s, got %s", scenario.ExpectedOutput, output)
 			}
 		})
 	}
 }
+
+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

@@ -1,17 +1,22 @@
 package provider
 
 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/mattermost"
-	"github.com/TwiN/gatus/v3/alerting/provider/messagebird"
-	"github.com/TwiN/gatus/v3/alerting/provider/pagerduty"
-	"github.com/TwiN/gatus/v3/alerting/provider/slack"
-	"github.com/TwiN/gatus/v3/alerting/provider/teams"
-	"github.com/TwiN/gatus/v3/alerting/provider/telegram"
-	"github.com/TwiN/gatus/v3/alerting/provider/twilio"
-	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/alerting/provider/custom"
+	"github.com/TwiN/gatus/v4/alerting/provider/discord"
+	"github.com/TwiN/gatus/v4/alerting/provider/email"
+	"github.com/TwiN/gatus/v4/alerting/provider/googlechat"
+	"github.com/TwiN/gatus/v4/alerting/provider/matrix"
+	"github.com/TwiN/gatus/v4/alerting/provider/mattermost"
+	"github.com/TwiN/gatus/v4/alerting/provider/messagebird"
+	"github.com/TwiN/gatus/v4/alerting/provider/ntfy"
+	"github.com/TwiN/gatus/v4/alerting/provider/opsgenie"
+	"github.com/TwiN/gatus/v4/alerting/provider/pagerduty"
+	"github.com/TwiN/gatus/v4/alerting/provider/slack"
+	"github.com/TwiN/gatus/v4/alerting/provider/teams"
+	"github.com/TwiN/gatus/v4/alerting/provider/telegram"
+	"github.com/TwiN/gatus/v4/alerting/provider/twilio"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 // AlertProvider is the interface that each providers should implement
@@ -19,11 +24,11 @@ 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
@@ -52,8 +57,13 @@ var (
 	// Validate interface implementation on compile
 	_ AlertProvider = (*custom.AlertProvider)(nil)
 	_ AlertProvider = (*discord.AlertProvider)(nil)
+	_ AlertProvider = (*email.AlertProvider)(nil)
+	_ AlertProvider = (*googlechat.AlertProvider)(nil)
+	_ AlertProvider = (*matrix.AlertProvider)(nil)
 	_ AlertProvider = (*mattermost.AlertProvider)(nil)
 	_ AlertProvider = (*messagebird.AlertProvider)(nil)
+	_ AlertProvider = (*ntfy.AlertProvider)(nil)
+	_ AlertProvider = (*opsgenie.AlertProvider)(nil)
 	_ AlertProvider = (*pagerduty.AlertProvider)(nil)
 	_ AlertProvider = (*slack.AlertProvider)(nil)
 	_ AlertProvider = (*teams.AlertProvider)(nil)

alerting/provider/provider_test.go

@@ -3,7 +3,7 @@ package provider
 import (
 	"testing"
 
-	"github.com/TwiN/gatus/v3/alerting/alert"
+	"github.com/TwiN/gatus/v4/alerting/alert"
 )
 
 func TestParseWithDefaultAlert(t *testing.T) {

alerting/provider/slack/slack.go

@@ -1,35 +1,72 @@
 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 // AlertProvider is the configuration necessary for sending an alert using Slack
 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"`
+	// 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"`
+	WebhookURL string `yaml:"webhook-url"`
 }
 
 // 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.WebhookURL) == 0 {
+				return false
+			}
+			registeredGroups[override.Group] = true
+		}
+	}
 	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.getWebhookURLForGroup(endpoint.Group), 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 +82,7 @@ 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 +99,19 @@ func (provider *AlertProvider) ToCustomAlertProvider(endpoint *core.Endpoint, al
       ]
     }
   ]
-}`, message, description, color, results),
-		Headers: map[string]string{"Content-Type": "application/json"},
+}`, message, description, color, results)
+}
+
+// getWebhookURLForGroup returns the appropriate Webhook URL integration to for a given group
+func (provider *AlertProvider) getWebhookURLForGroup(group string) string {
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if group == override.Group {
+				return override.WebhookURL
+			}
+		}
 	}
+	return provider.WebhookURL
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/slack/slack_test.go

@@ -3,68 +3,275 @@ package slack
 import (
 	"encoding/json"
 	"net/http"
-	"strings"
 	"testing"
 
-	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/test"
 )
 
-func TestAlertProvider_IsValid(t *testing.T) {
+func TestAlertDefaultProvider_IsValid(t *testing.T) {
 	invalidProvider := AlertProvider{WebhookURL: ""}
 	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_IsValidWithOverride(t *testing.T) {
+	providerWithInvalidOverrideGroup := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "",
+			},
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "resolved") {
-		t.Error("customAlertProvider.Body should've contained the substring resolved")
+	if providerWithInvalidOverrideGroup.IsValid() {
+		t.Error("provider Group shouldn't have been valid")
 	}
-	if customAlertProvider.URL != "http://example.com" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
+	providerWithInvalidOverrideTo := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "",
+				Group:      "group",
+			},
+		},
 	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	if providerWithInvalidOverrideTo.IsValid() {
+		t.Error("provider integration key shouldn't have been valid")
 	}
-	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())
+	providerWithValidOverride := AlertProvider{
+		WebhookURL: "http://example.com",
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "group",
+			},
+		},
 	}
-	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"])
+	if !providerWithValidOverride.IsValid() {
+		t.Error("provider should've been valid")
 	}
 }
 
-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_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, "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) {
+			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_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}",
+		},
+	}
+	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")
+	}
+}
+
+func TestAlertProvider_getWebhookURLForGroup(t *testing.T) {
+	tests := []struct {
+		Name           string
+		Provider       AlertProvider
+		InputGroup     string
+		ExpectedOutput string
+	}{
+		{
+			Name: "provider-no-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-no-override-specify-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-group-should-override",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example01.com",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.Name, func(t *testing.T) {
+			if got := tt.Provider.getWebhookURLForGroup(tt.InputGroup); got != tt.ExpectedOutput {
+				t.Errorf("AlertProvider.getWebhookURLForGroup() = %v, want %v", got, tt.ExpectedOutput)
+			}
+		})
 	}
 }

alerting/provider/teams/teams.go

@@ -1,12 +1,14 @@
 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 // AlertProvider is the configuration necessary for sending an alert using Teams
@@ -14,23 +16,59 @@ 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"`
+
+	// 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"`
+	WebhookURL string `yaml:"webhook-url"`
 }
 
 // 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.WebhookURL) == 0 {
+				return false
+			}
+			registeredGroups[override.Group] = true
+		}
+	}
 	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.getWebhookURLForGroup(endpoint.Group), 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 +85,7 @@ 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 +101,19 @@ 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)
+}
+
+// getWebhookURLForGroup returns the appropriate Webhook URL integration to for a given group
+func (provider *AlertProvider) getWebhookURLForGroup(group string) string {
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if group == override.Group {
+				return override.WebhookURL
+			}
+		}
 	}
+	return provider.WebhookURL
 }
 
 // GetDefaultAlert returns the provider's default alert configuration

alerting/provider/teams/teams_test.go

@@ -3,14 +3,15 @@ package teams
 import (
 	"encoding/json"
 	"net/http"
-	"strings"
 	"testing"
 
-	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/test"
 )
 
-func TestAlertProvider_IsValid(t *testing.T) {
+func TestAlertDefaultProvider_IsValid(t *testing.T) {
 	invalidProvider := AlertProvider{WebhookURL: ""}
 	if invalidProvider.IsValid() {
 		t.Error("provider shouldn't have been valid")
@@ -21,50 +22,237 @@ 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_IsValidWithOverride(t *testing.T) {
+	providerWithInvalidOverrideGroup := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "",
+			},
+		},
 	}
-	if !strings.Contains(customAlertProvider.Body, "resolved") {
-		t.Error("customAlertProvider.Body should've contained the substring resolved")
+	if providerWithInvalidOverrideGroup.IsValid() {
+		t.Error("provider Group shouldn't have been valid")
 	}
-	if customAlertProvider.URL != "http://example.org" {
-		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
+	providerWithInvalidOverrideTo := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "",
+				Group:      "group",
+			},
+		},
 	}
-	if customAlertProvider.Method != http.MethodPost {
-		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	if providerWithInvalidOverrideTo.IsValid() {
+		t.Error("provider integration key shouldn't have been valid")
 	}
-	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())
+	providerWithValidOverride := AlertProvider{
+		WebhookURL: "http://example.com",
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "group",
+			},
+		},
 	}
-	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"])
+	if !providerWithValidOverride.IsValid() {
+		t.Error("provider should've been valid")
 	}
 }
 
-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_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, "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) {
+			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_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}",
+		},
+	}
+	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")
+	}
+}
+
+func TestAlertProvider_getWebhookURLForGroup(t *testing.T) {
+	tests := []struct {
+		Name           string
+		Provider       AlertProvider
+		InputGroup     string
+		ExpectedOutput string
+	}{
+		{
+			Name: "provider-no-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-no-override-specify-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-group-should-override",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example01.com",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.Name, func(t *testing.T) {
+			if got := tt.Provider.getWebhookURLForGroup(tt.InputGroup); got != tt.ExpectedOutput {
+				t.Errorf("AlertProvider.getToForGroup() = %v, want %v", got, tt.ExpectedOutput)
+			}
+		})
 	}
 }

alerting/provider/telegram/telegram.go

@@ -1,35 +1,69 @@
 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/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"`
+
+	// 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"`
+	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.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(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, 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 +80,7 @@ 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

@@ -2,90 +2,167 @@ package telegram
 
 import (
 	"encoding/json"
-	"fmt"
 	"net/http"
-	"strings"
 	"testing"
 
-	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/test"
 )
 
 func TestAlertProvider_IsValid(t *testing.T) {
-	invalidProvider := AlertProvider{Token: "", ID: ""}
-	if invalidProvider.IsValid() {
-		t.Error("provider shouldn't have been valid")
+	t.Run("invalid-provider", func(t *testing.T) {
+		invalidProvider := AlertProvider{Token: "", ID: ""}
+		if invalidProvider.IsValid() {
+			t.Error("provider shouldn't have been valid")
+		}
+	})
+	t.Run("valid-provider", func(t *testing.T) {
+		validProvider := AlertProvider{Token: "123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11", ID: "12345678"}
+		if validProvider.ClientConfig != nil {
+			t.Error("provider client config should have been nil prior to IsValid() being executed")
+		}
+		if !validProvider.IsValid() {
+			t.Error("provider should've been valid")
+		}
+		if validProvider.ClientConfig == nil {
+			t.Error("provider client config should have been set after IsValid() was executed")
+		}
+	})
+}
+
+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,
+		},
 	}
-	validProvider := AlertProvider{Token: "123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11", ID: "12345678"}
-	if !validProvider.IsValid() {
-		t.Error("provider should've been valid")
+	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_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_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, "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) {
+			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_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_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())
-	}
-}
-
-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")
-	}
-	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

@@ -1,14 +1,16 @@
 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/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 // AlertProvider is the configuration necessary for sending an alert using Twilio
@@ -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

@@ -1,12 +1,10 @@
 package twilio
 
 import (
-	"net/http"
-	"strings"
 	"testing"
 
-	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 func TestTwilioAlertProvider_IsValid(t *testing.T) {
@@ -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"
 )
 
-// GetHTTPClient returns the shared HTTP client
+// injectedHTTPClient is used for testing purposes
+var injectedHTTPClient *http.Client
+
+// GetHTTPClient returns the shared HTTP client, or the client from the configuration passed
 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"
+	"net/http"
 	"testing"
 	"time"
+
+	"github.com/TwiN/gatus/v4/test"
 )
 
 func TestGetHTTPClient(t *testing.T) {
@@ -10,8 +15,18 @@ func TestGetHTTPClient(t *testing.T) {
 		Insecure:       false,
 		IgnoreRedirect: false,
 		Timeout:        0,
+		DNSResolver:    "tcp://1.1.1.1:53",
+		OAuth2Config: &OAuth2Config{
+			ClientID:     "00000000-0000-0000-0000-000000000000",
+			ClientSecret: "secretsauce",
+			TokenURL:     "https://token-server.local/token",
+			Scopes:       []string{"https://application.local/.default"},
+		},
+	}
+	err := cfg.ValidateAndSetDefaults()
+	if err != nil {
+		t.Errorf("expected error to be nil, but got: `%s`", err)
 	}
-	cfg.ValidateAndSetDefaults()
 	if GetHTTPClient(cfg) == nil {
 		t.Error("expected client to not be nil")
 	}
@@ -146,3 +161,61 @@ 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: io.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 +1,18 @@
 package client
 
 import (
+	"context"
 	"crypto/tls"
+	"errors"
+	"log"
+	"net"
 	"net/http"
+	"regexp"
+	"strconv"
 	"time"
+
+	"golang.org/x/oauth2"
+	"golang.org/x/oauth2/clientcredentials"
 )
 
 const (
@@ -11,7 +20,10 @@ const (
 )
 
 var (
-	// DefaultConfig is the default client configuration
+	ErrInvalidDNSResolver        = errors.New("invalid DNS resolver specified. Required format is {proto}://{ip}:{port}")
+	ErrInvalidDNSResolverPort    = errors.New("invalid DNS resolver port")
+	ErrInvalidClientOAuth2Config = errors.New("invalid OAuth2 configuration, all fields are required")
+
 	defaultConfig = Config{
 		Insecure:       false,
 		IgnoreRedirect: false,
@@ -28,22 +40,99 @@ 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"`
 
+	// DNSResolver override for the HTTP client
+	// Expected format is {protocol}://{host}:{port}, e.g. tcp://1.1.1.1:53
+	DNSResolver string `yaml:"dns-resolver,omitempty"`
+
+	// 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
 }
 
+// DNSResolverConfig is the parsed configuration from the DNSResolver config string.
+type DNSResolverConfig struct {
+	Protocol string
+	Host     string
+	Port     string
+}
+
+// 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.HasCustomDNSResolver() {
+		// Validate the DNS resolver now to make sure it will not return an error later.
+		if _, err := c.parseDNSResolver(); err != nil {
+			return err
+		}
+	}
+	if c.HasOAuth2Config() && !c.OAuth2Config.isValid() {
+		return ErrInvalidClientOAuth2Config
+	}
+	return nil
+}
+
+// HasCustomDNSResolver returns whether a custom DNSResolver is configured
+func (c *Config) HasCustomDNSResolver() bool {
+	return len(c.DNSResolver) > 0
+}
+
+// parseDNSResolver parses the DNS resolver into the DNSResolverConfig struct
+func (c *Config) parseDNSResolver() (*DNSResolverConfig, error) {
+	re := regexp.MustCompile(`^(?P<proto>(.*))://(?P<host>[A-Za-z0-9\-\.]+):(?P<port>[0-9]+)?(.*)$`)
+	matches := re.FindStringSubmatch(c.DNSResolver)
+	if len(matches) == 0 {
+		return nil, ErrInvalidDNSResolver
+	}
+	r := make(map[string]string)
+	for i, k := range re.SubexpNames() {
+		if i != 0 && k != "" {
+			r[k] = matches[i]
+		}
+	}
+	port, err := strconv.Atoi(r["port"])
+	if err != nil {
+		return nil, err
+	}
+	if port < 1 || port > 65535 {
+		return nil, ErrInvalidDNSResolverPort
+	}
+	return &DNSResolverConfig{
+		Protocol: r["proto"],
+		Host:     r["host"],
+		Port:     r["port"],
+	}, 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 +157,43 @@ func (c *Config) getHTTPClient() *http.Client {
 				return nil
 			},
 		}
+		if c.HasCustomDNSResolver() {
+			dnsResolver, err := c.parseDNSResolver()
+			if err != nil {
+				// We're ignoring the error, because it should have been validated on startup ValidateAndSetDefaults.
+				// It shouldn't happen, but if it does, we'll log it... Better safe than sorry ;)
+				log.Println("[client][getHTTPClient] THIS SHOULD NOT HAPPEN. Silently ignoring invalid DNS resolver due to error:", err.Error())
+			} else {
+				dialer := &net.Dialer{
+					Resolver: &net.Resolver{
+						PreferGo: true,
+						Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
+							d := net.Dialer{}
+							return d.DialContext(ctx, dnsResolver.Protocol, dnsResolver.Host+":"+dnsResolver.Port)
+						},
+					},
+				}
+				c.httpClient.Transport.(*http.Transport).DialContext = func(ctx context.Context, network, addr string) (net.Conn, error) {
+					return dialer.DialContext(ctx, network, addr)
+				}
+			}
+		}
+		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)
+}

client/config_test.go

@@ -35,3 +35,47 @@ func TestConfig_getHTTPClient(t *testing.T) {
 		t.Error("expected Config.IgnoreRedirect set to true to cause the HTTP client's CheckRedirect to return http.ErrUseLastResponse")
 	}
 }
+
+func TestConfig_ValidateAndSetDefaults_withCustomDNSResolver(t *testing.T) {
+	type args struct {
+		dnsResolver string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		wantErr bool
+	}{
+		{
+			name: "with-valid-resolver",
+			args: args{
+				dnsResolver: "tcp://1.1.1.1:53",
+			},
+			wantErr: false,
+		},
+		{
+			name: "with-invalid-resolver-port",
+			args: args{
+				dnsResolver: "tcp://127.0.0.1:99999",
+			},
+			wantErr: true,
+		},
+		{
+			name: "with-invalid-resolver-format",
+			args: args{
+				dnsResolver: "foobar",
+			},
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cfg := &Config{
+				DNSResolver: tt.args.dnsResolver,
+			}
+			err := cfg.ValidateAndSetDefaults()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("ValidateAndSetDefaults() error=%v, wantErr=%v", err, tt.wantErr)
+			}
+		})
+	}
+}

config.yaml

@@ -31,7 +31,7 @@ endpoints:
       - "[STATUS] == 200"
 
   - name: example-dns-query
-    url: "8.8.8.8" # Address of the DNS server to use
+    url: "1.1.1.1" # Address of the DNS server to use
     interval: 5m
     dns:
       query-name: "example.com"
@@ -45,3 +45,9 @@ endpoints:
     interval: 1m
     conditions:
       - "[CONNECTED] == true"
+
+  - name: check-domain-expiration
+    url: "https://example.org/"
+    interval: 1h
+    conditions:
+      - "[DOMAIN_EXPIRATION] > 720h"

config/config.go

@@ -2,20 +2,22 @@ package config
 
 import (
 	"errors"
-	"io/ioutil"
+	"fmt"
 	"log"
 	"os"
 	"time"
 
-	"github.com/TwiN/gatus/v3/alerting"
-	"github.com/TwiN/gatus/v3/alerting/alert"
-	"github.com/TwiN/gatus/v3/alerting/provider"
-	"github.com/TwiN/gatus/v3/config/maintenance"
-	"github.com/TwiN/gatus/v3/config/ui"
-	"github.com/TwiN/gatus/v3/config/web"
-	"github.com/TwiN/gatus/v3/core"
-	"github.com/TwiN/gatus/v3/security"
-	"github.com/TwiN/gatus/v3/storage"
+	"github.com/TwiN/gatus/v4/alerting"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/alerting/provider"
+	"github.com/TwiN/gatus/v4/config/maintenance"
+	"github.com/TwiN/gatus/v4/config/remote"
+	"github.com/TwiN/gatus/v4/config/ui"
+	"github.com/TwiN/gatus/v4/config/web"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/security"
+	"github.com/TwiN/gatus/v4/storage"
+	"github.com/TwiN/gatus/v4/util"
 	"gopkg.in/yaml.v2"
 )
 
@@ -43,28 +45,28 @@ var (
 // Config is the main configuration structure
 type Config struct {
 	// Debug Whether to enable debug logs
-	Debug bool `yaml:"debug"`
+	Debug bool `yaml:"debug,omitempty"`
 
 	// Metrics Whether to expose metrics at /metrics
-	Metrics bool `yaml:"metrics"`
+	Metrics bool `yaml:"metrics,omitempty"`
 
 	// SkipInvalidConfigUpdate Whether to make the application ignore invalid configuration
 	// if the configuration file is updated while the application is running
-	SkipInvalidConfigUpdate bool `yaml:"skip-invalid-config-update"`
+	SkipInvalidConfigUpdate bool `yaml:"skip-invalid-config-update,omitempty"`
 
 	// DisableMonitoringLock Whether to disable the monitoring lock
 	// The monitoring lock is what prevents multiple endpoints from being processed at the same time.
 	// Disabling this may lead to inaccurate response times
-	DisableMonitoringLock bool `yaml:"disable-monitoring-lock"`
+	DisableMonitoringLock bool `yaml:"disable-monitoring-lock,omitempty"`
 
 	// Security Configuration for securing access to Gatus
-	Security *security.Config `yaml:"security"`
+	Security *security.Config `yaml:"security,omitempty"`
 
 	// Alerting Configuration for alerting
-	Alerting *alerting.Config `yaml:"alerting"`
+	Alerting *alerting.Config `yaml:"alerting,omitempty"`
 
 	// Endpoints List of endpoints to monitor
-	Endpoints []*core.Endpoint `yaml:"endpoints"`
+	Endpoints []*core.Endpoint `yaml:"endpoints,omitempty"`
 
 	// Services List of endpoints to monitor
 	//
@@ -72,24 +74,38 @@ type Config struct {
 	// XXX: This is not a typo -- not v4.0.0, but v5.0.0 -- I want to give enough time for people to migrate
 	//
 	// Deprecated in favor of Endpoints
-	Services []*core.Endpoint `yaml:"services"`
+	Services []*core.Endpoint `yaml:"services,omitempty"`
 
 	// Storage is the configuration for how the data is stored
-	Storage *storage.Config `yaml:"storage"`
+	Storage *storage.Config `yaml:"storage,omitempty"`
 
 	// Web is the web configuration for the application
-	Web *web.Config `yaml:"web"`
+	Web *web.Config `yaml:"web,omitempty"`
 
 	// UI is the configuration for the UI
-	UI *ui.Config `yaml:"ui"`
+	UI *ui.Config `yaml:"ui,omitempty"`
 
 	// Maintenance is the configuration for creating a maintenance window in which no alerts are sent
-	Maintenance *maintenance.Config `yaml:"maintenance"`
+	Maintenance *maintenance.Config `yaml:"maintenance,omitempty"`
+
+	// Remote is the configuration for remote Gatus instances
+	// WARNING: This is in ALPHA and may change or be completely removed in the future
+	Remote *remote.Config `yaml:"remote,omitempty"`
 
 	filePath        string    // path to the file from which config was loaded from
 	lastFileModTime time.Time // last modification time
 }
 
+func (config *Config) GetEndpointByKey(key string) *core.Endpoint {
+	for i := 0; i < len(config.Endpoints); i++ {
+		ep := config.Endpoints[i]
+		if util.ConvertGroupAndEndpointNameToKey(ep.Group, ep.Name) == key {
+			return ep
+		}
+	}
+	return nil
+}
+
 // HasLoadedConfigurationFileBeenModified returns whether the file that the
 // configuration has been loaded from has been modified since it was last read
 func (config Config) HasLoadedConfigurationFileBeenModified() bool {
@@ -142,19 +158,19 @@ 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)
 	}
 	return
 }
 
+// parseAndValidateConfigBytes parses a Gatus configuration file into a Config struct and validates its parameters
 func parseAndValidateConfigBytes(yamlBytes []byte) (config *Config, err error) {
 	// Expand environment variables
 	yamlBytes = []byte(os.ExpandEnv(string(yamlBytes)))
 	// Parse configuration file
-	err = yaml.Unmarshal(yamlBytes, &config)
-	if err != nil {
+	if err = yaml.Unmarshal(yamlBytes, &config); err != nil {
 		return
 	}
 	if config != nil && len(config.Services) > 0 { // XXX: Remove this in v5.0.0
@@ -167,8 +183,6 @@ func parseAndValidateConfigBytes(yamlBytes []byte) (config *Config, err error) {
 	if config == nil || config.Endpoints == nil || len(config.Endpoints) == 0 {
 		err = ErrNoEndpointInConfig
 	} else {
-		// Note that the functions below may panic, and this is on purpose to prevent Gatus from starting with
-		// invalid configurations
 		validateAlertingConfig(config.Alerting, config.Endpoints, config.Debug)
 		if err := validateSecurityConfig(config); err != nil {
 			return nil, err
@@ -188,28 +202,31 @@ func parseAndValidateConfigBytes(yamlBytes []byte) (config *Config, err error) {
 		if err := validateStorageConfig(config); err != nil {
 			return nil, err
 		}
+		if err := validateRemoteConfig(config); err != nil {
+			return nil, err
+		}
 	}
 	return
 }
 
+func validateRemoteConfig(config *Config) error {
+	if config.Remote != nil {
+		if err := config.Remote.ValidateAndSetDefaults(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func validateStorageConfig(config *Config) error {
 	if config.Storage == nil {
 		config.Storage = &storage.Config{
 			Type: storage.TypeMemory,
 		}
-	}
-	err := storage.Initialize(config.Storage)
-	if err != nil {
-		return err
-	}
-	// Remove all EndpointStatus that represent endpoints which no longer exist in the configuration
-	var keys []string
-	for _, endpoint := range config.Endpoints {
-		keys = append(keys, endpoint.Key())
-	}
-	numberOfEndpointStatusesDeleted := storage.Get().DeleteAllEndpointStatusesNotInKeys(keys)
-	if numberOfEndpointStatusesDeleted > 0 {
-		log.Printf("[config][validateStorageConfig] Deleted %d endpoint statuses because their matching endpoints no longer existed", numberOfEndpointStatusesDeleted)
+	} else {
+		if err := config.Storage.ValidateAndSetDefaults(); err != nil {
+			return err
+		}
 	}
 	return nil
 }
@@ -251,7 +268,7 @@ func validateEndpointsConfig(config *Config) error {
 			log.Printf("[config][validateEndpointsConfig] Validating endpoint '%s'", endpoint.Name)
 		}
 		if err := endpoint.ValidateAndSetDefaults(); err != nil {
-			return err
+			return fmt.Errorf("invalid endpoint %s: %s", endpoint.DisplayName(), err)
 		}
 	}
 	log.Printf("[config][validateEndpointsConfig] Validated %d endpoints", len(config.Endpoints))
@@ -285,8 +302,12 @@ func validateAlertingConfig(alertingConfig *alerting.Config, endpoints []*core.E
 	alertTypes := []alert.Type{
 		alert.TypeCustom,
 		alert.TypeDiscord,
+		alert.TypeEmail,
+		alert.TypeMatrix,
 		alert.TypeMattermost,
 		alert.TypeMessagebird,
+		alert.TypeNtfy,
+		alert.TypeOpsgenie,
 		alert.TypePagerDuty,
 		alert.TypeSlack,
 		alert.TypeTeams,

config/config_test.go

@@ -5,21 +5,21 @@ import (
 	"testing"
 	"time"
 
-	"github.com/TwiN/gatus/v3/alerting"
-	"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/mattermost"
-	"github.com/TwiN/gatus/v3/alerting/provider/messagebird"
-	"github.com/TwiN/gatus/v3/alerting/provider/pagerduty"
-	"github.com/TwiN/gatus/v3/alerting/provider/slack"
-	"github.com/TwiN/gatus/v3/alerting/provider/teams"
-	"github.com/TwiN/gatus/v3/alerting/provider/telegram"
-	"github.com/TwiN/gatus/v3/alerting/provider/twilio"
-	"github.com/TwiN/gatus/v3/client"
-	"github.com/TwiN/gatus/v3/config/ui"
-	"github.com/TwiN/gatus/v3/config/web"
-	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v4/alerting"
+	"github.com/TwiN/gatus/v4/alerting/alert"
+	"github.com/TwiN/gatus/v4/alerting/provider/custom"
+	"github.com/TwiN/gatus/v4/alerting/provider/discord"
+	"github.com/TwiN/gatus/v4/alerting/provider/mattermost"
+	"github.com/TwiN/gatus/v4/alerting/provider/messagebird"
+	"github.com/TwiN/gatus/v4/alerting/provider/pagerduty"
+	"github.com/TwiN/gatus/v4/alerting/provider/slack"
+	"github.com/TwiN/gatus/v4/alerting/provider/teams"
+	"github.com/TwiN/gatus/v4/alerting/provider/telegram"
+	"github.com/TwiN/gatus/v4/alerting/provider/twilio"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/config/web"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/storage"
 )
 
 func TestLoadFileThatDoesNotExist(t *testing.T) {
@@ -38,20 +38,24 @@ func TestLoadDefaultConfigurationFile(t *testing.T) {
 
 func TestParseAndValidateConfigBytes(t *testing.T) {
 	file := t.TempDir() + "/test.db"
-	ui.StaticFolder = "../web/static"
-	defer func() {
-		ui.StaticFolder = "./web/static"
-	}()
 	config, err := parseAndValidateConfigBytes([]byte(fmt.Sprintf(`
 storage:
-  file: %s
+  type: sqlite
+  path: %s
 maintenance:
   enabled: true
   start: 00:00
   duration: 4h
   every: [Monday, Thursday]
 ui:
-  title: Test
+  title: T
+  header: H
+  link: https://example.org
+  buttons:
+    - name: "Home"
+      link: "https://example.org"
+    - name: "Status page"
+      link: "https://status.example.org"
 endpoints:
   - name: website
     url: https://twin.sh/health
@@ -83,8 +87,11 @@ endpoints:
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
 	}
-	if config.UI == nil || config.UI.Title != "Test" {
-		t.Error("Expected Config.UI.Title to be Test")
+	if config.Storage == nil || config.Storage.Path != file || config.Storage.Type != storage.TypeSQLite {
+		t.Error("expected storage to be set to sqlite, got", config.Storage)
+	}
+	if config.UI == nil || config.UI.Title != "T" || config.UI.Header != "H" || config.UI.Link != "https://example.org" || len(config.UI.Buttons) != 2 || config.UI.Buttons[0].Name != "Home" || config.UI.Buttons[0].Link != "https://example.org" || config.UI.Buttons[1].Name != "Status page" || config.UI.Buttons[1].Link != "https://status.example.org" {
+		t.Error("expected ui to be set to T, H, https://example.org, 2 buttons, Home and Status page, got", config.UI)
 	}
 	if mc := config.Maintenance; mc == nil || mc.Start != "00:00" || !mc.IsEnabled() || mc.Duration != 4*time.Hour || len(mc.Every) != 2 {
 		t.Error("Expected Config.Maintenance to be configured properly")
@@ -1113,7 +1120,7 @@ endpoints:
     conditions:
       - "[STATUS] == 200"
 `))
-	if err != core.ErrEndpointWithNoName {
+	if err == nil {
 		t.Error("should've returned an error")
 	}
 }
@@ -1167,12 +1174,12 @@ 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
@@ -1197,8 +1204,8 @@ 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.PasswordBcryptHashBase64Encoded)
 	}
 }
 

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/maintenance/maintenance_test.go

@@ -98,6 +98,15 @@ func TestConfig_ValidateAndSetDefaults(t *testing.T) {
 			},
 			expectedError: nil,
 		},
+		{
+			name: "every-day-explicitly-at-2300",
+			cfg: &Config{
+				Start:    "23:00",
+				Duration: time.Hour,
+				Every:    []string{"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"},
+			},
+			expectedError: nil,
+		},
 		{
 			name: "every-monday-at-0000",
 			cfg: &Config{
@@ -168,6 +177,24 @@ func TestConfig_IsUnderMaintenance(t *testing.T) {
 			},
 			expected: true,
 		},
+		{
+			name: "under-maintenance-starting-now-for-8h-explicit-days",
+			cfg: &Config{
+				Start:    fmt.Sprintf("%02d:00", now.Hour()),
+				Duration: 8 * time.Hour,
+				Every:    []string{"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"},
+			},
+			expected: true,
+		},
+		{
+			name: "under-maintenance-starting-now-for-23h-explicit-days",
+			cfg: &Config{
+				Start:    fmt.Sprintf("%02d:00", now.Hour()),
+				Duration: 23 * time.Hour,
+				Every:    []string{"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"},
+			},
+			expected: true,
+		},
 		{
 			name: "under-maintenance-starting-4h-ago-for-8h",
 			cfg: &Config{
@@ -176,6 +203,14 @@ func TestConfig_IsUnderMaintenance(t *testing.T) {
 			},
 			expected: true,
 		},
+		{
+			name: "under-maintenance-starting-22h-ago-for-23h",
+			cfg: &Config{
+				Start:    fmt.Sprintf("%02d:00", normalizeHour(now.Hour()-22)),
+				Duration: 23 * time.Hour,
+			},
+			expected: true,
+		},
 		{
 			name: "under-maintenance-starting-4h-ago-for-3h",
 			cfg: &Config{

config/remote/remote.go

@@ -0,0 +1,39 @@
+package remote
+
+import (
+	"log"
+
+	"github.com/TwiN/gatus/v4/client"
+)
+
+// NOTICE: This is an experimental alpha feature and may be updated/removed in future versions.
+// For more information, see https://github.com/TwiN/gatus/issues/64
+
+type Config struct {
+	// Instances is a list of remote instances to retrieve endpoint statuses from.
+	Instances []Instance `yaml:"instances,omitempty"`
+
+	// ClientConfig is the configuration of the client used to communicate with the provider's target
+	ClientConfig *client.Config `yaml:"client,omitempty"`
+}
+
+type Instance struct {
+	EndpointPrefix string `yaml:"endpoint-prefix"`
+	URL            string `yaml:"url"`
+}
+
+func (c *Config) ValidateAndSetDefaults() error {
+	if c.ClientConfig == nil {
+		c.ClientConfig = client.GetDefaultConfig()
+	} else {
+		if err := c.ClientConfig.ValidateAndSetDefaults(); err != nil {
+			return err
+		}
+	}
+	if len(c.Instances) > 0 {
+		log.Println("WARNING: Your configuration is using 'remote', which is in alpha and may be updated/removed in future versions.")
+		log.Println("WARNING: See https://github.com/TwiN/gatus/issues/64 for more information")
+		log.Println("WARNING: This feature is a candidate for removal in future versions. Please comment on the issue above if you need this feature.")
+	}
+	return nil
+}

config/ui/ui.go

@@ -2,31 +2,53 @@ package ui
 
 import (
 	"bytes"
+	"errors"
 	"html/template"
+
+	"github.com/TwiN/gatus/v4/web"
 )
 
 const (
-	defaultTitle = "Health Dashboard | Gatus"
-	defaultLogo  = ""
+	defaultTitle  = "Health Dashboard | Gatus"
+	defaultHeader = "Health Status"
+	defaultLogo   = ""
+	defaultLink   = ""
 )
 
 var (
-	// StaticFolder is the path to the location of the static folder from the root path of the project
-	// The only reason this is exposed is to allow running tests from a different path than the root path of the project
-	StaticFolder = "./web/static"
+	ErrButtonValidationFailed = errors.New("invalid button configuration: missing required name or link")
 )
 
 // 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
+	Buttons []Button `yaml:"buttons,omitempty"` // Buttons to display below the header
+}
+
+// Button is the configuration for a button on the UI
+type Button struct {
+	Name string `yaml:"name,omitempty"` // Name is the text to display on the button
+	Link string `yaml:"link,omitempty"` // Link to open when the button is clicked.
+}
+
+// Validate validates the button configuration
+func (btn *Button) Validate() error {
+	if len(btn.Name) == 0 || len(btn.Link) == 0 {
+		return ErrButtonValidationFailed
+	}
+	return nil
 }
 
 // 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,
 	}
 }
 
@@ -35,7 +57,19 @@ func (cfg *Config) ValidateAndSetDefaults() error {
 	if len(cfg.Title) == 0 {
 		cfg.Title = defaultTitle
 	}
-	t, err := template.ParseFiles(StaticFolder + "/index.html")
+	if len(cfg.Header) == 0 {
+		cfg.Header = defaultHeader
+	}
+	if len(cfg.Header) == 0 {
+		cfg.Header = defaultLink
+	}
+	for _, btn := range cfg.Buttons {
+		if err := btn.Validate(); err != nil {
+			return err
+		}
+	}
+	// Validate that the template works
+	t, err := template.ParseFS(static.FileSystem, static.IndexPath)
 	if err != nil {
 		return err
 	}

config/ui/ui_test.go

@@ -1,18 +1,65 @@
 package ui
 
 import (
+	"strconv"
 	"testing"
 )
 
 func TestConfig_ValidateAndSetDefaults(t *testing.T) {
-	StaticFolder = "../../web/static"
-	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 TestButton_Validate(t *testing.T) {
+	scenarios := []struct {
+		Name, Link    string
+		ExpectedError error
+	}{
+		{
+			Name:          "",
+			Link:          "",
+			ExpectedError: ErrButtonValidationFailed,
+		},
+		{
+			Name:          "",
+			Link:          "link",
+			ExpectedError: ErrButtonValidationFailed,
+		},
+		{
+			Name:          "name",
+			Link:          "",
+			ExpectedError: ErrButtonValidationFailed,
+		},
+		{
+			Name:          "name",
+			Link:          "link",
+			ExpectedError: nil,
+		},
+	}
+	for i, scenario := range scenarios {
+		t.Run(strconv.Itoa(i)+"_"+scenario.Name+"_"+scenario.Link, func(t *testing.T) {
+			button := &Button{
+				Name: scenario.Name,
+				Link: scenario.Link,
+			}
+			if err := button.Validate(); err != scenario.ExpectedError {
+				t.Errorf("expected error %v, got %v", scenario.ExpectedError, err)
+			}
+		})
+	}
 }
 
 func TestGetDefaultConfig(t *testing.T) {

controller/controller.go

@@ -8,10 +8,8 @@ import (
 	"os"
 	"time"
 
-	"github.com/TwiN/gatus/v3/config/ui"
-	"github.com/TwiN/gatus/v3/config/web"
-	"github.com/TwiN/gatus/v3/controller/handler"
-	"github.com/TwiN/gatus/v3/security"
+	"github.com/TwiN/gatus/v4/config"
+	"github.com/TwiN/gatus/v4/controller/handler"
 )
 
 var (
@@ -21,19 +19,19 @@ var (
 )
 
 // Handle creates the router and starts the server
-func Handle(securityConfig *security.Config, webConfig *web.Config, uiConfig *ui.Config, enableMetrics bool) {
-	var router http.Handler = handler.CreateRouter(ui.StaticFolder, securityConfig, uiConfig, enableMetrics)
+func Handle(cfg *config.Config) {
+	var router http.Handler = handler.CreateRouter(cfg)
 	if os.Getenv("ENVIRONMENT") == "dev" {
 		router = handler.DevelopmentCORS(router)
 	}
 	server = &http.Server{
-		Addr:         fmt.Sprintf("%s:%d", webConfig.Address, webConfig.Port),
+		Addr:         fmt.Sprintf("%s:%d", cfg.Web.Address, cfg.Web.Port),
 		Handler:      router,
 		ReadTimeout:  15 * time.Second,
 		WriteTimeout: 15 * time.Second,
 		IdleTimeout:  15 * time.Second,
 	}
-	log.Println("[controller][Handle] Listening on " + webConfig.SocketAddress())
+	log.Println("[controller][Handle] Listening on " + cfg.Web.SocketAddress())
 	if os.Getenv("ROUTER_TEST") == "true" {
 		return
 	}

controller/controller_test.go

@@ -7,9 +7,9 @@ import (
 	"os"
 	"testing"
 
-	"github.com/TwiN/gatus/v3/config"
-	"github.com/TwiN/gatus/v3/config/web"
-	"github.com/TwiN/gatus/v3/core"
+	"github.com/TwiN/gatus/v4/config"
+	"github.com/TwiN/gatus/v4/config/web"
+	"github.com/TwiN/gatus/v4/core"
 )
 
 func TestHandle(t *testing.T) {
@@ -32,9 +32,9 @@ func TestHandle(t *testing.T) {
 	_ = os.Setenv("ROUTER_TEST", "true")
 	_ = os.Setenv("ENVIRONMENT", "dev")
 	defer os.Clearenv()
-	Handle(cfg.Security, cfg.Web, cfg.UI, cfg.Metrics)
+	Handle(cfg)
 	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

@@ -7,8 +7,10 @@ import (
 	"strings"
 	"time"
 
-	"github.com/TwiN/gatus/v3/storage"
-	"github.com/TwiN/gatus/v3/storage/store/common"
+	"github.com/TwiN/gatus/v4/config"
+	"github.com/TwiN/gatus/v4/storage/store"
+	"github.com/TwiN/gatus/v4/storage/store/common"
+	"github.com/TwiN/gatus/v4/storage/store/common/paging"
 	"github.com/gorilla/mux"
 )
 
@@ -21,6 +23,16 @@ const (
 	badgeColorHexVeryBad  = "#c7130a"
 )
 
+const (
+	HealthStatusUp      = "up"
+	HealthStatusDown    = "down"
+	HealthStatusUnknown = "?"
+)
+
+var (
+	badgeColors = []string{badgeColorHexAwesome, badgeColorHexGreat, badgeColorHexGood, badgeColorHexPassable, badgeColorHexBad}
+)
+
 // UptimeBadge handles the automatic generation of badge based on the group name and endpoint name passed.
 //
 // Valid values for {duration}: 7d, 24h, 1h
@@ -40,63 +52,92 @@ func UptimeBadge(writer http.ResponseWriter, request *http.Request) {
 		return
 	}
 	key := variables["key"]
-	uptime, err := storage.Get().GetUptimeByKey(key, from, time.Now())
+	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))
 }
 
 // ResponseTimeBadge handles the automatic generation of badge based on the group name and endpoint name passed.
 //
 // Valid values for {duration}: 7d, 24h, 1h
-func ResponseTimeBadge(writer http.ResponseWriter, request *http.Request) {
-	variables := mux.Vars(request)
-	duration := variables["duration"]
-	var from time.Time
-	switch duration {
-	case "7d":
-		from = time.Now().Add(-7 * 24 * time.Hour)
-	case "24h":
-		from = time.Now().Add(-24 * time.Hour)
-	case "1h":
-		from = time.Now().Add(-2 * time.Hour) // Because response time metrics are stored by hour, we have to cheat a little
-	default:
-		http.Error(writer, "Durations supported: 7d, 24h, 1h", http.StatusBadRequest)
-		return
+func ResponseTimeBadge(config *config.Config) http.HandlerFunc {
+	return func(writer http.ResponseWriter, request *http.Request) {
+		variables := mux.Vars(request)
+		duration := variables["duration"]
+		var from time.Time
+		switch duration {
+		case "7d":
+			from = time.Now().Add(-7 * 24 * time.Hour)
+		case "24h":
+			from = time.Now().Add(-24 * time.Hour)
+		case "1h":
+			from = time.Now().Add(-2 * time.Hour) // Because response time metrics are stored by hour, we have to cheat a little
+		default:
+			http.Error(writer, "Durations supported: 7d, 24h, 1h", http.StatusBadRequest)
+			return
+		}
+		key := variables["key"]
+		averageResponseTime, err := store.Get().GetAverageResponseTimeByKey(key, from, time.Now())
+		if err != nil {
+			if err == common.ErrEndpointNotFound {
+				http.Error(writer, err.Error(), http.StatusNotFound)
+			} else if err == common.ErrInvalidTimeRange {
+				http.Error(writer, err.Error(), http.StatusBadRequest)
+			} else {
+				http.Error(writer, err.Error(), http.StatusInternalServerError)
+			}
+			return
+		}
+		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, key, config))
 	}
+}
+
+// HealthBadge handles the automatic generation of badge based on the group name and endpoint name passed.
+func HealthBadge(writer http.ResponseWriter, request *http.Request) {
+	variables := mux.Vars(request)
 	key := variables["key"]
-	averageResponseTime, err := storage.Get().GetAverageResponseTimeByKey(key, from, time.Now())
+	pagingConfig := paging.NewEndpointStatusParams()
+	status, err := store.Get().GetEndpointStatusByKey(key, pagingConfig.WithResults(1, 1))
 	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)
+	healthStatus := HealthStatusUnknown
+	if len(status.Results) > 0 {
+		if status.Results[0].Success {
+			healthStatus = HealthStatusUp
+		} else {
+			healthStatus = HealthStatusDown
+		}
+	}
 	writer.Header().Set("Content-Type", "image/svg+xml")
-	_, _ = writer.Write(generateResponseTimeBadgeSVG(duration, averageResponseTime))
+	writer.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
+	writer.Header().Set("Expires", "0")
+	writer.WriteHeader(http.StatusOK)
+	_, _ = writer.Write(generateHealthBadgeSVG(healthStatus))
 }
 
 func generateUptimeBadgeSVG(duration string, uptime float64) []byte {
@@ -165,7 +206,7 @@ func getBadgeColorFromUptime(uptime float64) string {
 	return badgeColorHexVeryBad
 }
 
-func generateResponseTimeBadgeSVG(duration string, averageResponseTime int) []byte {
+func generateResponseTimeBadgeSVG(duration string, averageResponseTime int, key string, cfg *config.Config) []byte {
 	var labelWidth, valueWidth int
 	switch duration {
 	case "7d":
@@ -176,7 +217,7 @@ func generateResponseTimeBadgeSVG(duration string, averageResponseTime int) []by
 		labelWidth = 105
 	default:
 	}
-	color := getBadgeColorFromResponseTime(averageResponseTime)
+	color := getBadgeColorFromResponseTime(averageResponseTime, key, cfg)
 	sanitizedValue := strconv.Itoa(averageResponseTime) + "ms"
 	valueWidth = len(sanitizedValue) * 11
 	width := labelWidth + valueWidth
@@ -213,17 +254,71 @@ func generateResponseTimeBadgeSVG(duration string, averageResponseTime int) []by
 	return svg
 }
 
-func getBadgeColorFromResponseTime(responseTime int) string {
-	if responseTime <= 50 {
-		return badgeColorHexAwesome
-	} else if responseTime <= 200 {
-		return badgeColorHexGreat
-	} else if responseTime <= 300 {
-		return badgeColorHexGood
-	} else if responseTime <= 500 {
-		return badgeColorHexPassable
-	} else if responseTime <= 750 {
-		return badgeColorHexBad
+func getBadgeColorFromResponseTime(responseTime int, key string, cfg *config.Config) string {
+	endpoint := cfg.GetEndpointByKey(key)
+	// the threshold config requires 5 values, so we can be sure it's set here
+	for i := 0; i < 5; i++ {
+		if responseTime <= endpoint.UIConfig.Badge.ResponseTime.Thresholds[i] {
+			return badgeColors[i]
+		}
 	}
 	return badgeColorHexVeryBad
 }
+
+func generateHealthBadgeSVG(healthStatus string) []byte {
+	var labelWidth, valueWidth int
+	switch healthStatus {
+	case HealthStatusUp:
+		valueWidth = 28
+	case HealthStatusDown:
+		valueWidth = 44
+	case HealthStatusUnknown:
+		valueWidth = 10
+	default:
+	}
+	color := getBadgeColorFromHealth(healthStatus)
+	labelWidth = 48
+
+	width := labelWidth + valueWidth
+	labelX := labelWidth / 2
+	valueX := labelWidth + (valueWidth / 2)
+	svg := []byte(fmt.Sprintf(`<svg xmlns="http://www.w3.org/2000/svg" width="%d" height="20">
+  <linearGradient id="b" x2="0" y2="100%%">
+    <stop offset="0" stop-color="#bbb" stop-opacity=".1"/>
+    <stop offset="1" stop-opacity=".1"/>
+  </linearGradient>
+  <mask id="a">
+    <rect width="%d" height="20" rx="3" fill="#fff"/>
+  </mask>
+  <g mask="url(#a)">
+    <path fill="#555" d="M0 0h%dv20H0z"/>
+    <path fill="%s" d="M%d 0h%dv20H%dz"/>
+    <path fill="url(#b)" d="M0 0h%dv20H0z"/>
+  </g>
+  <g fill="#fff" text-anchor="middle" font-family="DejaVu Sans,Verdana,Geneva,sans-serif" font-size="11">
+    <text x="%d" y="15" fill="#010101" fill-opacity=".3">
+      health
+    </text>
+    <text x="%d" y="14">
+      health
+    </text>
+    <text x="%d" y="15" fill="#010101" fill-opacity=".3">
+      %s
+    </text>
+    <text x="%d" y="14">
+      %s
+    </text>
+  </g>
+</svg>`, width, width, labelWidth, color, labelWidth, valueWidth, labelWidth, width, labelX, labelX, valueX, healthStatus, valueX, healthStatus))
+
+	return svg
+}
+
+func getBadgeColorFromHealth(healthStatus string) string {
+	if healthStatus == HealthStatusUp {
+		return badgeColorHexAwesome
+	} else if healthStatus == HealthStatusDown {
+		return badgeColorHexVeryBad
+	}
+	return badgeColorHexPassable
+}

controller/handler/badge_test.go

@@ -7,14 +7,15 @@ import (
 	"testing"
 	"time"
 
-	"github.com/TwiN/gatus/v3/config"
-	"github.com/TwiN/gatus/v3/core"
-	"github.com/TwiN/gatus/v3/storage"
-	"github.com/TwiN/gatus/v3/watchdog"
+	"github.com/TwiN/gatus/v4/config"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/core/ui"
+	"github.com/TwiN/gatus/v4/storage/store"
+	"github.com/TwiN/gatus/v4/watchdog"
 )
 
-func TestUptimeBadge(t *testing.T) {
-	defer storage.Get().Clear()
+func TestBadge(t *testing.T) {
+	defer store.Get().Clear()
 	defer cache.Clear()
 	cfg := &config.Config{
 		Metrics: true,
@@ -29,9 +30,39 @@ func TestUptimeBadge(t *testing.T) {
 			},
 		},
 	}
-	watchdog.UpdateEndpointStatuses(cfg.Endpoints[0], &core.Result{Success: true, Duration: time.Millisecond, Timestamp: time.Now()})
-	watchdog.UpdateEndpointStatuses(cfg.Endpoints[1], &core.Result{Success: false, Duration: time.Second, Timestamp: time.Now()})
-	router := CreateRouter("../../web/static", cfg.Security, nil, cfg.Metrics)
+
+	testSuccessfulResult = core.Result{
+		Hostname:              "example.org",
+		IP:                    "127.0.0.1",
+		HTTPStatus:            200,
+		Errors:                nil,
+		Connected:             true,
+		Success:               true,
+		Timestamp:             timestamp,
+		Duration:              150 * time.Millisecond,
+		CertificateExpiration: 10 * time.Hour,
+		ConditionResults: []*core.ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   true,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   true,
+			},
+		},
+	}
+
+	cfg.Endpoints[0].UIConfig = ui.GetDefaultConfig()
+	cfg.Endpoints[1].UIConfig = ui.GetDefaultConfig()
+
+	watchdog.UpdateEndpointStatuses(cfg.Endpoints[0], &core.Result{Success: true, Connected: true, Duration: time.Millisecond, Timestamp: time.Now()})
+	watchdog.UpdateEndpointStatuses(cfg.Endpoints[1], &core.Result{Success: false, Connected: false, Duration: time.Second, Timestamp: time.Now()})
+	router := CreateRouter(cfg)
 	type Scenario struct {
 		Name         string
 		Path         string
@@ -89,25 +120,40 @@ func TestUptimeBadge(t *testing.T) {
 			Path:         "/api/v1/endpoints/invalid_key/response-times/7d/badge.svg",
 			ExpectedCode: http.StatusNotFound,
 		},
+		{
+			Name:         "badge-health-up",
+			Path:         "/api/v1/endpoints/core_frontend/health/badge.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badge-health-down",
+			Path:         "/api/v1/endpoints/core_backend/health/badge.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badge-health-for-invalid-key",
+			Path:         "/api/v1/endpoints/invalid_key/health/badge.svg",
+			ExpectedCode: http.StatusNotFound,
+		},
 		{
 			Name:         "chart-response-time-24h",
 			Path:         "/api/v1/endpoints/core_backend/response-times/24h/chart.svg",
 			ExpectedCode: http.StatusOK,
 		},
-		{ // XXX: Remove this in v4.0.0
-			Name:         "backward-compatible-services-badge-uptime-1h",
-			Path:         "/api/v1/services/core_frontend/uptimes/1h/badge.svg",
+		{
+			Name:         "chart-response-time-7d",
+			Path:         "/api/v1/endpoints/core_frontend/response-times/7d/chart.svg",
 			ExpectedCode: http.StatusOK,
 		},
-		{ // XXX: Remove this in v4.0.0
-			Name:         "backward-compatible-services-chart-response-time-24h",
-			Path:         "/api/v1/services/core_backend/response-times/24h/chart.svg",
-			ExpectedCode: http.StatusOK,
+		{
+			Name:         "chart-response-time-with-invalid-duration",
+			Path:         "/api/v1/endpoints/core_backend/response-times/3d/chart.svg",
+			ExpectedCode: http.StatusBadRequest,
 		},
 	}
 	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")
 			}
@@ -176,55 +222,155 @@ func TestGetBadgeColorFromUptime(t *testing.T) {
 }
 
 func TestGetBadgeColorFromResponseTime(t *testing.T) {
+	defer store.Get().Clear()
+	defer cache.Clear()
+
+	var (
+		firstCondition  = core.Condition("[STATUS] == 200")
+		secondCondition = core.Condition("[RESPONSE_TIME] < 500")
+		thirdCondition  = core.Condition("[CERTIFICATE_EXPIRATION] < 72h")
+	)
+
+	firstTestEndpoint := core.Endpoint{
+		Name:                    "a",
+		URL:                     "https://example.org/what/ever",
+		Method:                  "GET",
+		Body:                    "body",
+		Interval:                30 * time.Second,
+		Conditions:              []core.Condition{firstCondition, secondCondition, thirdCondition},
+		Alerts:                  nil,
+		NumberOfFailuresInARow:  0,
+		NumberOfSuccessesInARow: 0,
+		UIConfig:                ui.GetDefaultConfig(),
+	}
+	secondTestEndpoint := core.Endpoint{
+		Name:                    "b",
+		URL:                     "https://example.org/what/ever",
+		Method:                  "GET",
+		Body:                    "body",
+		Interval:                30 * time.Second,
+		Conditions:              []core.Condition{firstCondition, secondCondition, thirdCondition},
+		Alerts:                  nil,
+		NumberOfFailuresInARow:  0,
+		NumberOfSuccessesInARow: 0,
+		UIConfig: &ui.Config{
+			Badge: &ui.Badge{
+				ResponseTime: &ui.ResponseTime{
+					Thresholds: []int{100, 500, 1000, 2000, 3000},
+				},
+			},
+		},
+	}
+	cfg := &config.Config{
+		Metrics:   true,
+		Endpoints: []*core.Endpoint{&firstTestEndpoint, &secondTestEndpoint},
+	}
+
+	store.Get().Insert(&firstTestEndpoint, &testSuccessfulResult)
+	store.Get().Insert(&secondTestEndpoint, &testSuccessfulResult)
+
 	scenarios := []struct {
+		Key           string
 		ResponseTime  int
 		ExpectedColor string
 	}{
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  10,
 			ExpectedColor: badgeColorHexAwesome,
 		},
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  50,
 			ExpectedColor: badgeColorHexAwesome,
 		},
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  75,
 			ExpectedColor: badgeColorHexGreat,
 		},
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  150,
 			ExpectedColor: badgeColorHexGreat,
 		},
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  201,
 			ExpectedColor: badgeColorHexGood,
 		},
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  300,
 			ExpectedColor: badgeColorHexGood,
 		},
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  301,
 			ExpectedColor: badgeColorHexPassable,
 		},
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  450,
 			ExpectedColor: badgeColorHexPassable,
 		},
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  700,
 			ExpectedColor: badgeColorHexBad,
 		},
 		{
+			Key:           firstTestEndpoint.Key(),
 			ResponseTime:  1500,
 			ExpectedColor: badgeColorHexVeryBad,
 		},
+		{
+			Key:           secondTestEndpoint.Key(),
+			ResponseTime:  50,
+			ExpectedColor: badgeColorHexAwesome,
+		},
+		{
+			Key:           secondTestEndpoint.Key(),
+			ResponseTime:  1500,
+			ExpectedColor: badgeColorHexPassable,
+		},
+		{
+			Key:           secondTestEndpoint.Key(),
+			ResponseTime:  2222,
+			ExpectedColor: badgeColorHexBad,
+		},
 	}
 	for _, scenario := range scenarios {
-		t.Run("response-time-"+strconv.Itoa(scenario.ResponseTime), func(t *testing.T) {
-			if getBadgeColorFromResponseTime(scenario.ResponseTime) != scenario.ExpectedColor {
-				t.Errorf("expected %s from %d, got %v", scenario.ExpectedColor, scenario.ResponseTime, getBadgeColorFromResponseTime(scenario.ResponseTime))
+		t.Run(scenario.Key+"-response-time-"+strconv.Itoa(scenario.ResponseTime), func(t *testing.T) {
+			if getBadgeColorFromResponseTime(scenario.ResponseTime, scenario.Key, cfg) != scenario.ExpectedColor {
+				t.Errorf("expected %s from %d, got %v", scenario.ExpectedColor, scenario.ResponseTime, getBadgeColorFromResponseTime(scenario.ResponseTime, scenario.Key, cfg))
+			}
+		})
+	}
+}
+
+func TestGetBadgeColorFromHealth(t *testing.T) {
+	scenarios := []struct {
+		HealthStatus  string
+		ExpectedColor string
+	}{
+		{
+			HealthStatus:  HealthStatusUp,
+			ExpectedColor: badgeColorHexAwesome,
+		},
+		{
+			HealthStatus:  HealthStatusDown,
+			ExpectedColor: badgeColorHexVeryBad,
+		},
+		{
+			HealthStatus:  HealthStatusUnknown,
+			ExpectedColor: badgeColorHexPassable,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run("health-"+scenario.HealthStatus, func(t *testing.T) {
+			if getBadgeColorFromHealth(scenario.HealthStatus) != scenario.ExpectedColor {
+				t.Errorf("expected %s from %s, got %v", scenario.ExpectedColor, scenario.HealthStatus, getBadgeColorFromHealth(scenario.HealthStatus))
 			}
 		})
 	}

controller/handler/chart.go

@@ -7,8 +7,8 @@ import (
 	"sort"
 	"time"
 
-	"github.com/TwiN/gatus/v3/storage"
-	"github.com/TwiN/gatus/v3/storage/store/common"
+	"github.com/TwiN/gatus/v4/storage/store"
+	"github.com/TwiN/gatus/v4/storage/store/common"
 	"github.com/gorilla/mux"
 	"github.com/wcharczuk/go-chart/v2"
 	"github.com/wcharczuk/go-chart/v2/drawing"
@@ -42,21 +42,19 @@ func ResponseTimeChart(writer http.ResponseWriter, r *http.Request) {
 		http.Error(writer, "Durations supported: 7d, 24h", http.StatusBadRequest)
 		return
 	}
-	hourlyAverageResponseTime, err := storage.Get().GetHourlyAverageResponseTimeByKey(vars["key"], from, time.Now())
+	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

@@ -6,14 +6,14 @@ import (
 	"testing"
 	"time"
 
-	"github.com/TwiN/gatus/v3/config"
-	"github.com/TwiN/gatus/v3/core"
-	"github.com/TwiN/gatus/v3/storage"
-	"github.com/TwiN/gatus/v3/watchdog"
+	"github.com/TwiN/gatus/v4/config"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/storage/store"
+	"github.com/TwiN/gatus/v4/watchdog"
 )
 
 func TestResponseTimeChart(t *testing.T) {
-	defer storage.Get().Clear()
+	defer store.Get().Clear()
 	defer cache.Clear()
 	cfg := &config.Config{
 		Metrics: true,
@@ -30,7 +30,7 @@ func TestResponseTimeChart(t *testing.T) {
 	}
 	watchdog.UpdateEndpointStatuses(cfg.Endpoints[0], &core.Result{Success: true, Duration: time.Millisecond, Timestamp: time.Now()})
 	watchdog.UpdateEndpointStatuses(cfg.Endpoints[1], &core.Result{Success: false, Duration: time.Second, Timestamp: time.Now()})
-	router := CreateRouter("../../web/static", cfg.Security, nil, cfg.Metrics)
+	router := CreateRouter(cfg)
 	type Scenario struct {
 		Name         string
 		Path         string
@@ -58,15 +58,10 @@ func TestResponseTimeChart(t *testing.T) {
 			Path:         "/api/v1/endpoints/invalid_key/response-times/7d/chart.svg",
 			ExpectedCode: http.StatusNotFound,
 		},
-		{ // XXX: Remove this in v4.0.0
-			Name:         "backward-compatible-services-chart-response-time-24h",
-			Path:         "/api/v1/services/core_backend/response-times/24h/chart.svg",
-			ExpectedCode: http.StatusOK,
-		},
 	}
 	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/v4/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/v4/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.go

@@ -5,15 +5,20 @@ import (
 	"compress/gzip"
 	"encoding/json"
 	"fmt"
+	"io"
 	"log"
 	"net/http"
 	"strings"
 	"time"
 
-	"github.com/TwiN/gatus/v3/storage"
-	"github.com/TwiN/gatus/v3/storage/store/common"
-	"github.com/TwiN/gatus/v3/storage/store/common/paging"
-	"github.com/TwiN/gocache"
+	"github.com/TwiN/gatus/v4/client"
+	"github.com/TwiN/gatus/v4/config"
+	"github.com/TwiN/gatus/v4/config/remote"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/storage/store"
+	"github.com/TwiN/gatus/v4/storage/store/common"
+	"github.com/TwiN/gatus/v4/storage/store/common/paging"
+	"github.com/TwiN/gocache/v2"
 	"github.com/gorilla/mux"
 )
 
@@ -28,55 +33,96 @@ var (
 // EndpointStatuses handles requests to retrieve all EndpointStatus
 // Due to the size of the response, this function leverages a cache.
 // Must not be wrapped by GzipHandler
-func EndpointStatuses(writer http.ResponseWriter, r *http.Request) {
-	page, pageSize := extractPageAndPageSizeFromRequest(r)
-	gzipped := strings.Contains(r.Header.Get("Accept-Encoding"), "gzip")
-	var exists bool
-	var value interface{}
-	if gzipped {
-		writer.Header().Set("Content-Encoding", "gzip")
-		value, exists = cache.Get(fmt.Sprintf("endpoint-status-%d-%d-gzipped", page, pageSize))
-	} else {
-		value, exists = cache.Get(fmt.Sprintf("endpoint-status-%d-%d", page, pageSize))
-	}
-	var data []byte
-	if !exists {
-		var err error
-		buffer := &bytes.Buffer{}
-		gzipWriter := gzip.NewWriter(buffer)
-		endpointStatuses, err := storage.Get().GetAllEndpointStatuses(paging.NewEndpointStatusParams().WithResults(page, pageSize))
-		if err != nil {
-			log.Printf("[handler][EndpointStatuses] Failed to retrieve endpoint statuses: %s", err.Error())
-			http.Error(writer, err.Error(), http.StatusInternalServerError)
-			return
-		}
-		data, err = json.Marshal(endpointStatuses)
-		if err != nil {
-			log.Printf("[handler][EndpointStatuses] Unable to marshal object to JSON: %s", err.Error())
-			http.Error(writer, "unable to marshal object to JSON", http.StatusInternalServerError)
-			return
-		}
-		_, _ = gzipWriter.Write(data)
-		_ = gzipWriter.Close()
-		gzippedData := buffer.Bytes()
-		cache.SetWithTTL(fmt.Sprintf("endpoint-status-%d-%d", page, pageSize), data, cacheTTL)
-		cache.SetWithTTL(fmt.Sprintf("endpoint-status-%d-%d-gzipped", page, pageSize), gzippedData, cacheTTL)
+func EndpointStatuses(cfg *config.Config) http.HandlerFunc {
+	return func(writer http.ResponseWriter, r *http.Request) {
+		page, pageSize := extractPageAndPageSizeFromRequest(r)
+		gzipped := strings.Contains(r.Header.Get("Accept-Encoding"), "gzip")
+		var exists bool
+		var value interface{}
 		if gzipped {
-			data = gzippedData
+			writer.Header().Set("Content-Encoding", "gzip")
+			value, exists = cache.Get(fmt.Sprintf("endpoint-status-%d-%d-gzipped", page, pageSize))
+		} else {
+			value, exists = cache.Get(fmt.Sprintf("endpoint-status-%d-%d", page, pageSize))
 		}
-	} else {
-		data = value.([]byte)
+		var data []byte
+		if !exists {
+			var err error
+			buffer := &bytes.Buffer{}
+			gzipWriter := gzip.NewWriter(buffer)
+			endpointStatuses, err := store.Get().GetAllEndpointStatuses(paging.NewEndpointStatusParams().WithResults(page, pageSize))
+			if err != nil {
+				log.Printf("[handler][EndpointStatuses] Failed to retrieve endpoint statuses: %s", err.Error())
+				http.Error(writer, err.Error(), http.StatusInternalServerError)
+				return
+			}
+			// ALPHA: Retrieve endpoint statuses from remote instances
+			if endpointStatusesFromRemote, err := getEndpointStatusesFromRemoteInstances(cfg.Remote); err != nil {
+				log.Printf("[handler][EndpointStatuses] Silently failed to retrieve endpoint statuses from remote: %s", err.Error())
+			} else if endpointStatusesFromRemote != nil {
+				endpointStatuses = append(endpointStatuses, endpointStatusesFromRemote...)
+			}
+			// Marshal endpoint statuses to JSON
+			data, err = json.Marshal(endpointStatuses)
+			if err != nil {
+				log.Printf("[handler][EndpointStatuses] Unable to marshal object to JSON: %s", err.Error())
+				http.Error(writer, "unable to marshal object to JSON", http.StatusInternalServerError)
+				return
+			}
+			_, _ = gzipWriter.Write(data)
+			_ = gzipWriter.Close()
+			gzippedData := buffer.Bytes()
+			cache.SetWithTTL(fmt.Sprintf("endpoint-status-%d-%d", page, pageSize), data, cacheTTL)
+			cache.SetWithTTL(fmt.Sprintf("endpoint-status-%d-%d-gzipped", page, pageSize), gzippedData, cacheTTL)
+			if gzipped {
+				data = gzippedData
+			}
+		} else {
+			data = value.([]byte)
+		}
+		writer.Header().Add("Content-Type", "application/json")
+		writer.WriteHeader(http.StatusOK)
+		_, _ = writer.Write(data)
 	}
-	writer.Header().Add("Content-Type", "application/json")
-	writer.WriteHeader(http.StatusOK)
-	_, _ = writer.Write(data)
+}
+
+func getEndpointStatusesFromRemoteInstances(remoteConfig *remote.Config) ([]*core.EndpointStatus, error) {
+	if remoteConfig == nil || len(remoteConfig.Instances) == 0 {
+		return nil, nil
+	}
+	var endpointStatusesFromAllRemotes []*core.EndpointStatus
+	httpClient := client.GetHTTPClient(remoteConfig.ClientConfig)
+	for _, instance := range remoteConfig.Instances {
+		response, err := httpClient.Get(instance.URL)
+		if err != nil {
+			return nil, err
+		}
+		body, err := io.ReadAll(response.Body)
+		if err != nil {
+			_ = response.Body.Close()
+			log.Printf("[handler][getEndpointStatusesFromRemoteInstances] Silently failed to retrieve endpoint statuses from %s: %s", instance.URL, err.Error())
+			continue
+		}
+		var endpointStatuses []*core.EndpointStatus
+		if err = json.Unmarshal(body, &endpointStatuses); err != nil {
+			_ = response.Body.Close()
+			log.Printf("[handler][getEndpointStatusesFromRemoteInstances] Silently failed to retrieve endpoint statuses from %s: %s", instance.URL, err.Error())
+			continue
+		}
+		_ = response.Body.Close()
+		for _, endpointStatus := range endpointStatuses {
+			endpointStatus.Name = instance.EndpointPrefix + endpointStatus.Name
+		}
+		endpointStatusesFromAllRemotes = append(endpointStatusesFromAllRemotes, endpointStatuses...)
+	}
+	return endpointStatusesFromAllRemotes, nil
 }
 
 // EndpointStatus retrieves a single core.EndpointStatus by group and endpoint name
 func EndpointStatus(writer http.ResponseWriter, r *http.Request) {
 	page, pageSize := extractPageAndPageSizeFromRequest(r)
 	vars := mux.Vars(r)
-	endpointStatus, err := storage.Get().GetEndpointStatusByKey(vars["key"], paging.NewEndpointStatusParams().WithResults(page, pageSize).WithEvents(1, common.MaximumNumberOfEvents))
+	endpointStatus, err := store.Get().GetEndpointStatusByKey(vars["key"], paging.NewEndpointStatusParams().WithResults(page, pageSize).WithEvents(1, common.MaximumNumberOfEvents))
 	if err != nil {
 		if err == common.ErrEndpointNotFound {
 			http.Error(writer, err.Error(), http.StatusNotFound)

controller/handler/endpoint_status_test.go

@@ -6,17 +6,13 @@ import (
 	"testing"
 	"time"
 
-	"github.com/TwiN/gatus/v3/config"
-	"github.com/TwiN/gatus/v3/core"
-	"github.com/TwiN/gatus/v3/storage"
-	"github.com/TwiN/gatus/v3/watchdog"
+	"github.com/TwiN/gatus/v4/config"
+	"github.com/TwiN/gatus/v4/core"
+	"github.com/TwiN/gatus/v4/storage/store"
+	"github.com/TwiN/gatus/v4/watchdog"
 )
 
 var (
-	firstCondition  = core.Condition("[STATUS] == 200")
-	secondCondition = core.Condition("[RESPONSE_TIME] < 500")
-	thirdCondition  = core.Condition("[CERTIFICATE_EXPIRATION] < 72h")
-
 	timestamp = time.Now()
 
 	testEndpoint = core.Endpoint{
@@ -26,7 +22,7 @@ var (
 		Method:                  "GET",
 		Body:                    "body",
 		Interval:                30 * time.Second,
-		Conditions:              []*core.Condition{&firstCondition, &secondCondition, &thirdCondition},
+		Conditions:              []core.Condition{core.Condition("[STATUS] == 200"), core.Condition("[RESPONSE_TIME] < 500"), core.Condition("[CERTIFICATE_EXPIRATION] < 72h")},
 		Alerts:                  nil,
 		NumberOfFailuresInARow:  0,
 		NumberOfSuccessesInARow: 0,
@@ -84,7 +80,7 @@ var (
 )
 
 func TestEndpointStatus(t *testing.T) {
-	defer storage.Get().Clear()
+	defer store.Get().Clear()
 	defer cache.Clear()
 	cfg := &config.Config{
 		Metrics: true,
@@ -101,7 +97,7 @@ func TestEndpointStatus(t *testing.T) {
 	}
 	watchdog.UpdateEndpointStatuses(cfg.Endpoints[0], &core.Result{Success: true, Duration: time.Millisecond, Timestamp: time.Now()})
 	watchdog.UpdateEndpointStatuses(cfg.Endpoints[1], &core.Result{Success: false, Duration: time.Second, Timestamp: time.Now()})
-	router := CreateRouter("../../web/static", cfg.Security, nil, cfg.Metrics)
+	router := CreateRouter(cfg)
 
 	type Scenario struct {
 		Name         string
@@ -131,15 +127,10 @@ func TestEndpointStatus(t *testing.T) {
 			Path:         "/api/v1/endpoints/invalid_key/statuses",
 			ExpectedCode: http.StatusNotFound,
 		},
-		{ // XXX: Remove this in v4.0.0
-			Name:         "backward-compatible-service-status",
-			Path:         "/api/v1/services/core_frontend/statuses",
-			ExpectedCode: http.StatusOK,
-		},
 	}
 	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")
 			}
@@ -153,16 +144,16 @@ func TestEndpointStatus(t *testing.T) {
 }
 
 func TestEndpointStatuses(t *testing.T) {
-	defer storage.Get().Clear()
+	defer store.Get().Clear()
 	defer cache.Clear()
 	firstResult := &testSuccessfulResult
 	secondResult := &testUnsuccessfulResult
-	storage.Get().Insert(&testEndpoint, firstResult)
-	storage.Get().Insert(&testEndpoint, secondResult)
+	store.Get().Insert(&testEndpoint, firstResult)
+	store.Get().Insert(&testEndpoint, secondResult)
 	// Can't be bothered dealing with timezone issues on the worker that runs the automated tests
 	firstResult.Timestamp = time.Time{}
 	secondResult.Timestamp = time.Time{}
-	router := CreateRouter("../../web/static", nil, nil, false)
+	router := CreateRouter(&config.Config{Metrics: true})
 
 	type Scenario struct {
 		Name         string
@@ -175,43 +166,37 @@ func TestEndpointStatuses(t *testing.T) {
 			Name:         "no-pagination",
 			Path:         "/api/v1/endpoints/statuses",
 			ExpectedCode: http.StatusOK,
-			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"errors":null,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"},{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}],"events":[]}]`,
+			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"},{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}]}]`,
 		},
 		{
 			Name:         "pagination-first-result",
 			Path:         "/api/v1/endpoints/statuses?page=1&pageSize=1",
 			ExpectedCode: http.StatusOK,
-			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}],"events":[]}]`,
+			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}]}]`,
 		},
 		{
 			Name:         "pagination-second-result",
 			Path:         "/api/v1/endpoints/statuses?page=2&pageSize=1",
 			ExpectedCode: http.StatusOK,
-			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"errors":null,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"}],"events":[]}]`,
+			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"}]}]`,
 		},
 		{
 			Name:         "pagination-no-results",
 			Path:         "/api/v1/endpoints/statuses?page=5&pageSize=20",
 			ExpectedCode: http.StatusOK,
-			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[],"events":[]}]`,
+			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[]}]`,
 		},
 		{
 			Name:         "invalid-pagination-should-fall-back-to-default",
 			Path:         "/api/v1/endpoints/statuses?page=INVALID&pageSize=INVALID",
 			ExpectedCode: http.StatusOK,
-			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"errors":null,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"},{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}],"events":[]}]`,
-		},
-		{ // XXX: Remove this in v4.0.0
-			Name:         "backward-compatible-service-status",
-			Path:         "/api/v1/services/statuses",
-			ExpectedCode: http.StatusOK,
-			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"errors":null,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"},{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}],"events":[]}]`,
+			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"},{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}]}]`,
 		},
 	}
 
 	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.go

@@ -1,12 +0,0 @@
-package handler
-
-import (
-	"net/http"
-)
-
-// FavIcon handles requests for /favicon.ico
-func FavIcon(staticFolder string) http.HandlerFunc {
-	return func(writer http.ResponseWriter, request *http.Request) {
-		http.ServeFile(writer, request, staticFolder+"/favicon.ico")
-	}
-}

controller/handler/favicon_test.go

@@ -1,33 +0,0 @@
-package handler
-
-import (
-	"net/http"
-	"net/http/httptest"
-	"testing"
-)
-
-func TestFavIcon(t *testing.T) {
-	router := CreateRouter("../../web/static", nil, nil, false)
-	type Scenario struct {
-		Name         string
-		Path         string
-		ExpectedCode int
-	}
-	scenarios := []Scenario{
-		{
-			Name:         "favicon",
-			Path:         "/favicon.ico",
-			ExpectedCode: http.StatusOK,
-		},
-	}
-	for _, scenario := range scenarios {
-		t.Run(scenario.Name, func(t *testing.T) {
-			request, _ := http.NewRequest("GET", scenario.Path, nil)
-			responseRecorder := httptest.NewRecorder()
-			router.ServeHTTP(responseRecorder, request)
-			if responseRecorder.Code != scenario.ExpectedCode {
-				t.Errorf("%s %s should have returned %d, but returned %d instead", request.Method, request.URL, scenario.ExpectedCode, responseRecorder.Code)
-			}
-		})
-	}
-}