Add configuration for whether to resolve failed conditions or not

This is technically a breaking change, but given how long ago this field was implemented as well as the fact that this is the default value if the type is not specified, I doubt anybody's explicitly setting it as inmemory

.dockerignore

@@ -1,5 +1,7 @@
-example
+examples
 Dockerfile
 .github
 .idea
 .git
+web/app
+*.db

.github/FUNDING.yml

@@ -0,0 +1 @@
+github: [TwinProduction]

.github/assets/gatus-diagram.drawio

@@ -0,0 +1 @@
+<mxfile host="app.diagrams.net" modified="2021-09-12T22:49:28.336Z" agent="5.0 (Windows)" etag="r9FJ6Bphqwq-LaTO-jp3" version="15.0.6" type="device"><diagram id="FBbfVOMCjf6Z2LK8Yagy" name="Page-1">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</diagram></mxfile>

.github/codecov.yml

@@ -1,5 +1,6 @@
 ignore:
   - "watchdog/watchdog.go"
+  - "storage/store/sql/specific_postgres.go" # Can't test for postgres
 
 coverage:
   status:

.github/workflows/build.yml

@@ -14,20 +14,20 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
-      - name: Set up Go 1.15
+      - name: Set up Go
         uses: actions/setup-go@v2
         with:
-          go-version: 1.15
+          go-version: 1.16
       - name: Check out code into the Go module directory
         uses: actions/checkout@v2
       - 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 "PATH=$PATH", we need it to use the same "go" executable that was configured by the "Set
-        # up Go" step (otherwise, it'd use sudo's "go" executable)
-        run: sudo "PATH=$PATH" go test -mod vendor ./... -race -coverprofile=coverage.txt -covermode=atomic
+        # 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)
+        run: sudo env "PATH=$PATH" "GOROOT=$GOROOT" go test -mod vendor ./... -race -coverprofile=coverage.txt -covermode=atomic
       - name: Codecov
-        uses: codecov/codecov-action@v1.0.14
+        uses: codecov/codecov-action@v1.5.2
         with:
           file: ./coverage.txt

.github/workflows/publish-latest.yml

@@ -0,0 +1,34 @@
+name: publish-latest
+on:
+  workflow_run:
+    workflows: ["build"]
+    branches: [master]
+    types: [completed]
+jobs:
+  publish-latest:
+    name: Publish latest
+    runs-on: ubuntu-latest
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+    timeout-minutes: 30
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v2
+      - name: Get image repository
+        run: echo IMAGE_REPOSITORY=$(echo ${{ github.repository }} | 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@v1
+        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 }}:latest

.github/workflows/publish-release.yml

@@ -0,0 +1,33 @@
+name: publish-release
+on:
+  release:
+    types: [published]
+jobs:
+  publish-release:
+    name: Publish release
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v2
+      - name: Get image repository
+        run: echo IMAGE_REPOSITORY=$(echo ${{ github.repository }} | tr '[:upper:]' '[:lower:]') >> $GITHUB_ENV
+      - name: Get the release
+        run: echo RELEASE=${GITHUB_REF/refs\/tags\//} >> $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@v1
+        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,linux/arm/v7,linux/arm64
+          pull: true
+          push: true
+          tags: |
+            ${{ env.IMAGE_REPOSITORY }}:${{ env.RELEASE }}

.github/workflows/publish.yml

@@ -1,32 +0,0 @@
-name: publish
-on:
-  release:
-    types: [published]
-jobs:
-  build:
-    name: Publish
-    runs-on: ubuntu-latest
-    steps:
-      - name: Check out code
-        uses: actions/checkout@v2
-      - name: Get image repository
-        run: echo IMAGE_REPOSITORY=$(echo ${{ github.repository }} | tr '[:upper:]' '[:lower:]') >> $GITHUB_ENV
-      - name: Get the release
-        run: echo RELEASE=${GITHUB_REF/refs\/tags\//} >> $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@v1
-        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,linux/arm/v7,linux/arm64
-          pull: true
-          push: true
-          tags: |
-            ${{ env.IMAGE_REPOSITORY }}:${{ env.RELEASE }}

.gitignore

@@ -1,4 +1,8 @@
-bin
 .idea
 .vscode
-gatus
+gatus
+db.db
+config/config.yml
+db.db-shm
+db.db-wal
+memory.db

Dockerfile

@@ -13,7 +13,7 @@ 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/static static/
+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.md

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2020 TwinProduction
+Copyright (c) 2021 TwinProduction
 
 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:
 

Makefile

@@ -0,0 +1,37 @@
+BINARY=gatus
+
+install:
+	go build -mod vendor -o $(BINARY) .
+
+run:
+	GATUS_CONFIG_FILE=./config.yaml ./$(BINARY)
+
+clean:
+	rm $(BINARY)
+
+test:
+	sudo go test ./alerting/... ./client/... ./config/... ./controller/... ./core/... ./jsonpath/... ./pattern/... ./security/... ./storage/... ./util/... ./watchdog/... -cover
+
+
+##########
+# Docker #
+##########
+
+docker-build:
+	docker build -t twinproduction/gatus:latest .
+
+docker-run:
+	docker run -p 8080:8080 --name gatus twinproduction/gatus:latest
+
+docker-build-and-run: docker-build docker-run
+
+
+#############
+# Front end #
+#############
+
+frontend-build:
+	npm --prefix web/app run build
+
+frontend-run:
+	npm --prefix web/app run serve

alerting/alert/alert.go

@@ -0,0 +1,69 @@
+package alert
+
+// Alert is the service's alert configuration
+type Alert struct {
+	// Type of alert (required)
+	Type Type `yaml:"type"`
+
+	// Enabled defines whether or not the alert is enabled
+	//
+	// 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"`
+
+	// FailureThreshold is the number of failures in a row needed before triggering the alert
+	FailureThreshold int `yaml:"failure-threshold"`
+
+	// Description of the alert. Will be included in the alert sent.
+	//
+	// 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.
+	Description *string `yaml:"description"`
+
+	// SendOnResolved defines whether to send a second notification when the issue has been resolved
+	//
+	// 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. Use Alert.IsSendingOnResolved() for a non-pointer
+	SendOnResolved *bool `yaml:"send-on-resolved"`
+
+	// SuccessThreshold defines how many successful executions must happen in a row before an ongoing incident is marked as resolved
+	SuccessThreshold int `yaml:"success-threshold"`
+
+	// ResolveKey is an optional field that is used by some providers (i.e. PagerDuty's dedup_key) to resolve
+	// ongoing/triggered incidents
+	ResolveKey string
+
+	// 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.
+	//
+	// This value should only be modified if the provider.AlertProvider's Send function does not return an error for an
+	// alert that hasn't been triggered yet. This doubles as a lazy retry. The reason why this behavior isn't also
+	// 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
+}
+
+// GetDescription retrieves the description of the alert
+func (alert Alert) GetDescription() string {
+	if alert.Description == nil {
+		return ""
+	}
+	return *alert.Description
+}
+
+// IsEnabled returns whether an alert is enabled or not
+func (alert Alert) IsEnabled() bool {
+	if alert.Enabled == nil {
+		return false
+	}
+	return *alert.Enabled
+}
+
+// IsSendingOnResolved returns whether an alert is sending on resolve or not
+func (alert Alert) IsSendingOnResolved() bool {
+	if alert.SendOnResolved == nil {
+		return false
+	}
+	return *alert.SendOnResolved
+}

alerting/alert/alert_test.go

@@ -0,0 +1,36 @@
+package alert
+
+import "testing"
+
+func TestAlert_IsEnabled(t *testing.T) {
+	if (Alert{Enabled: nil}).IsEnabled() {
+		t.Error("alert.IsEnabled() should've returned false, because Enabled was set to nil")
+	}
+	if value := false; (Alert{Enabled: &value}).IsEnabled() {
+		t.Error("alert.IsEnabled() should've returned false, because Enabled was set to false")
+	}
+	if value := true; !(Alert{Enabled: &value}).IsEnabled() {
+		t.Error("alert.IsEnabled() should've returned true, because Enabled was set to true")
+	}
+}
+
+func TestAlert_GetDescription(t *testing.T) {
+	if (Alert{Description: nil}).GetDescription() != "" {
+		t.Error("alert.GetDescription() should've returned an empty string, because Description was set to nil")
+	}
+	if value := "description"; (Alert{Description: &value}).GetDescription() != value {
+		t.Error("alert.GetDescription() should've returned false, because Description was set to 'description'")
+	}
+}
+
+func TestAlert_IsSendingOnResolved(t *testing.T) {
+	if (Alert{SendOnResolved: nil}).IsSendingOnResolved() {
+		t.Error("alert.IsSendingOnResolved() should've returned false, because SendOnResolved was set to nil")
+	}
+	if value := false; (Alert{SendOnResolved: &value}).IsSendingOnResolved() {
+		t.Error("alert.IsSendingOnResolved() should've returned false, because SendOnResolved was set to false")
+	}
+	if value := true; !(Alert{SendOnResolved: &value}).IsSendingOnResolved() {
+		t.Error("alert.IsSendingOnResolved() should've returned true, because SendOnResolved was set to true")
+	}
+}

alerting/alert/type.go

@@ -0,0 +1,34 @@
+package alert
+
+// Type is the type of the alert.
+// The value will generally be the name of the alert provider
+type Type string
+
+const (
+	// TypeCustom is the Type for the custom alerting provider
+	TypeCustom Type = "custom"
+
+	// TypeDiscord is the Type for the discord alerting provider
+	TypeDiscord Type = "discord"
+
+	// TypeMattermost is the Type for the mattermost alerting provider
+	TypeMattermost Type = "mattermost"
+
+	// TypeMessagebird is the Type for the messagebird alerting provider
+	TypeMessagebird Type = "messagebird"
+
+	// TypePagerDuty is the Type for the pagerduty alerting provider
+	TypePagerDuty Type = "pagerduty"
+
+	// TypeSlack is the Type for the slack alerting provider
+	TypeSlack Type = "slack"
+
+	// TypeTeams is the Type for the teams alerting provider
+	TypeTeams Type = "teams"
+
+	// TypeTelegram is the Type for the telegram alerting provider
+	TypeTelegram Type = "telegram"
+
+	// TypeTwilio is the Type for the twilio alerting provider
+	TypeTwilio Type = "twilio"
+)

alerting/config.go

@@ -1,18 +1,26 @@
 package alerting
 
 import (
+	"github.com/TwinProduction/gatus/alerting/alert"
+	"github.com/TwinProduction/gatus/alerting/provider"
 	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/alerting/provider/discord"
 	"github.com/TwinProduction/gatus/alerting/provider/mattermost"
 	"github.com/TwinProduction/gatus/alerting/provider/messagebird"
 	"github.com/TwinProduction/gatus/alerting/provider/pagerduty"
 	"github.com/TwinProduction/gatus/alerting/provider/slack"
+	"github.com/TwinProduction/gatus/alerting/provider/teams"
+	"github.com/TwinProduction/gatus/alerting/provider/telegram"
 	"github.com/TwinProduction/gatus/alerting/provider/twilio"
 )
 
 // Config is the configuration for alerting providers
 type Config struct {
-	// Slack is the configuration for the slack alerting provider
-	Slack *slack.AlertProvider `yaml:"slack"`
+	// Custom is the configuration for the custom alerting provider
+	Custom *custom.AlertProvider `yaml:"custom"`
+
+	// Discord is the configuration for the discord alerting provider
+	Discord *discord.AlertProvider `yaml:"discord"`
 
 	// Mattermost is the configuration for the mattermost alerting provider
 	Mattermost *mattermost.AlertProvider `yaml:"mattermost"`
@@ -20,12 +28,79 @@ type Config struct {
 	// Messagebird is the configuration for the messagebird alerting provider
 	Messagebird *messagebird.AlertProvider `yaml:"messagebird"`
 
-	// Pagerduty is the configuration for the pagerduty alerting provider
+	// PagerDuty is the configuration for the pagerduty alerting provider
 	PagerDuty *pagerduty.AlertProvider `yaml:"pagerduty"`
 
+	// Slack is the configuration for the slack alerting provider
+	Slack *slack.AlertProvider `yaml:"slack"`
+
+	// Teams is the configuration for the teams alerting provider
+	Teams *teams.AlertProvider `yaml:"teams"`
+
+	// Telegram is the configuration for the telegram alerting provider
+	Telegram *telegram.AlertProvider `yaml:"telegram"`
+
 	// Twilio is the configuration for the twilio alerting provider
 	Twilio *twilio.AlertProvider `yaml:"twilio"`
-
-	// Custom is the configuration for the custom alerting provider
-	Custom *custom.AlertProvider `yaml:"custom"`
+}
+
+// GetAlertingProviderByAlertType returns an provider.AlertProvider by its corresponding alert.Type
+func (config Config) GetAlertingProviderByAlertType(alertType alert.Type) provider.AlertProvider {
+	switch alertType {
+	case alert.TypeCustom:
+		if config.Custom == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Custom
+	case alert.TypeDiscord:
+		if config.Discord == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Discord
+	case alert.TypeMattermost:
+		if config.Mattermost == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Mattermost
+	case alert.TypeMessagebird:
+		if config.Messagebird == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Messagebird
+	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
+			return nil
+		}
+		return config.PagerDuty
+	case alert.TypeSlack:
+		if config.Slack == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Slack
+	case alert.TypeTeams:
+		if config.Teams == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Teams
+	case alert.TypeTelegram:
+		if config.Telegram == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Telegram
+	case alert.TypeTwilio:
+		if config.Twilio == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Twilio
+	}
+	return nil
 }

alerting/provider/custom/custom.go

@@ -9,6 +9,7 @@ import (
 	"os"
 	"strings"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/client"
 	"github.com/TwinProduction/gatus/core"
 )
@@ -16,27 +17,51 @@ import (
 // AlertProvider is the configuration necessary for sending an alert using a custom HTTP request
 // Technically, all alert providers should be reachable using the custom alert provider
 type AlertProvider struct {
-	URL      string            `yaml:"url"`
-	Method   string            `yaml:"method,omitempty"`
-	Insecure bool              `yaml:"insecure,omitempty"`
-	Body     string            `yaml:"body,omitempty"`
-	Headers  map[string]string `yaml:"headers,omitempty"`
+	URL          string                       `yaml:"url"`
+	Method       string                       `yaml:"method,omitempty"`
+	Body         string                       `yaml:"body,omitempty"`
+	Headers      map[string]string            `yaml:"headers,omitempty"`
+	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"`
+
+	// DefaultAlert is the default alert configuration to use for services with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert"`
 }
 
 // IsValid returns whether the provider's configuration is valid
 func (provider *AlertProvider) IsValid() bool {
-	return len(provider.URL) > 0
+	if provider.ClientConfig == nil {
+		provider.ClientConfig = client.GetDefaultConfig()
+	}
+	return len(provider.URL) > 0 && provider.ClientConfig != nil
 }
 
 // ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *core.Alert, result *core.Result, resolved bool) *AlertProvider {
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, 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"
+	if resolved {
+		status = "RESOLVED"
+	}
+	if _, ok := provider.Placeholders["ALERT_TRIGGERED_OR_RESOLVED"]; ok {
+		if val, ok := provider.Placeholders["ALERT_TRIGGERED_OR_RESOLVED"][status]; ok {
+			return val
+		}
+	}
+	return status
+}
+
 func (provider *AlertProvider) buildHTTPRequest(serviceName, 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)
 	}
@@ -45,9 +70,9 @@ func (provider *AlertProvider) buildHTTPRequest(serviceName, alertDescription st
 	}
 	if strings.Contains(body, "[ALERT_TRIGGERED_OR_RESOLVED]") {
 		if resolved {
-			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", "RESOLVED")
+			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(true))
 		} else {
-			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", "TRIGGERED")
+			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(false))
 		}
 	}
 	if strings.Contains(providerURL, "[ALERT_DESCRIPTION]") {
@@ -58,9 +83,9 @@ func (provider *AlertProvider) buildHTTPRequest(serviceName, alertDescription st
 	}
 	if strings.Contains(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]") {
 		if resolved {
-			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", "RESOLVED")
+			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(true))
 		} else {
-			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", "TRIGGERED")
+			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(false))
 		}
 	}
 	if len(method) == 0 {
@@ -83,7 +108,7 @@ func (provider *AlertProvider) Send(serviceName, alertDescription string, resolv
 		return []byte("{}"), nil
 	}
 	request := provider.buildHTTPRequest(serviceName, alertDescription, resolved)
-	response, err := client.GetHTTPClient(provider.Insecure).Do(request)
+	response, err := client.GetHTTPClient(provider.ClientConfig).Do(request)
 	if err != nil {
 		return nil, err
 	}
@@ -96,3 +121,8 @@ func (provider *AlertProvider) Send(serviceName, alertDescription string, resolv
 	}
 	return ioutil.ReadAll(response.Body)
 }
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/custom/custom_test.go

@@ -4,6 +4,7 @@ import (
 	"io/ioutil"
 	"testing"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/core"
 )
 
@@ -60,11 +61,51 @@ func TestAlertProvider_buildHTTPRequestWhenTriggered(t *testing.T) {
 
 func TestAlertProvider_ToCustomAlertProvider(t *testing.T) {
 	provider := AlertProvider{URL: "http://example.com"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, true)
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &alert.Alert{}, &core.Result{}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
-	if customAlertProvider != customAlertProvider {
-		t.Error("customAlertProvider should've been equal to customAlertProvider")
+	if customAlertProvider.URL != "http://example.com" {
+		t.Error("expected URL to be http://example.com, got", customAlertProvider.URL)
+	}
+}
+
+func TestAlertProvider_buildHTTPRequestWithCustomPlaceholder(t *testing.T) {
+	const (
+		ExpectedURL  = "http://example.com/service-name?event=test&description=alert-description"
+		ExpectedBody = "service-name,alert-description,test"
+	)
+	customAlertProvider := &AlertProvider{
+		URL:     "http://example.com/[SERVICE_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
+		Body:    "[SERVICE_NAME],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
+		Headers: nil,
+		Placeholders: map[string]map[string]string{
+			"ALERT_TRIGGERED_OR_RESOLVED": {
+				"RESOLVED": "test",
+			},
+		},
+	}
+	request := customAlertProvider.buildHTTPRequest("service-name", "alert-description", true)
+	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_GetAlertStatePlaceholderValueDefaults(t *testing.T) {
+	customAlertProvider := &AlertProvider{
+		URL:          "http://example.com/[SERVICE_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
+		Body:         "[SERVICE_NAME],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
+		Headers:      nil,
+		Placeholders: nil,
+	}
+	if customAlertProvider.GetAlertStatePlaceholderValue(true) != "RESOLVED" {
+		t.Error("expected RESOLVED, got", customAlertProvider.GetAlertStatePlaceholderValue(true))
+	}
+	if customAlertProvider.GetAlertStatePlaceholderValue(false) != "TRIGGERED" {
+		t.Error("expected TRIGGERED, got", customAlertProvider.GetAlertStatePlaceholderValue(false))
 	}
 }

alerting/provider/discord/discord.go

@@ -0,0 +1,76 @@
+package discord
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/TwinProduction/gatus/alerting/alert"
+	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/core"
+)
+
+// AlertProvider is the configuration necessary for sending an alert using Discord
+type AlertProvider struct {
+	WebhookURL string `yaml:"webhook-url"`
+
+	// DefaultAlert is the default alert configuration to use for services with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert"`
+}
+
+// IsValid returns whether the provider's configuration is valid
+func (provider *AlertProvider) IsValid() bool {
+	return len(provider.WebhookURL) > 0
+}
+
+// ToCustomAlertProvider converts the provider into a custom.AlertProvider
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
+	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", service.Name, 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", service.Name, alert.FailureThreshold)
+		colorCode = 15158332
+	}
+	for _, conditionResult := range result.ConditionResults {
+		var prefix string
+		if conditionResult.Success {
+			prefix = ":white_check_mark:"
+		} else {
+			prefix = ":x:"
+		}
+		results += fmt.Sprintf("%s - `%s`\\n", prefix, conditionResult.Condition)
+	}
+	var description string
+	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
+		description = ":\\n> " + alertDescription
+	}
+	return &custom.AlertProvider{
+		URL:    provider.WebhookURL,
+		Method: http.MethodPost,
+		Body: fmt.Sprintf(`{
+  "content": "",
+  "embeds": [
+    {
+      "title": ":helmet_with_white_cross: Gatus",
+      "description": "%s%s",
+      "color": %d,
+      "fields": [
+        {
+          "name": "Condition results",
+          "value": "%s",
+          "inline": false
+        }
+      ]
+    }
+  ]
+}`, message, description, colorCode, results),
+		Headers: map[string]string{"Content-Type": "application/json"},
+	}
+}
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/discord/discord_test.go

@@ -0,0 +1,70 @@
+package discord
+
+import (
+	"encoding/json"
+	"net/http"
+	"strings"
+	"testing"
+
+	"github.com/TwinProduction/gatus/alerting/alert"
+	"github.com/TwinProduction/gatus/core"
+)
+
+func TestAlertProvider_IsValid(t *testing.T) {
+	invalidProvider := AlertProvider{WebhookURL: ""}
+	if invalidProvider.IsValid() {
+		t.Error("provider shouldn't have been valid")
+	}
+	validProvider := AlertProvider{WebhookURL: "http://example.com"}
+	if !validProvider.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
+func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
+	provider := AlertProvider{WebhookURL: "http://example.com"}
+	alertDescription := "test"
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{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")
+	}
+	if !strings.Contains(customAlertProvider.Body, "resolved") {
+		t.Error("customAlertProvider.Body should've contained the substring resolved")
+	}
+	if customAlertProvider.URL != "http://example.com" {
+		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
+	if expected := "An alert for **svc** has been resolved after passing successfully 0 time(s) in a row:\n> test"; expected != body["embeds"].([]interface{})[0].(map[string]interface{})["description"] {
+		t.Errorf("expected $.embeds[0].description to be %s, got %s", expected, body["embeds"].([]interface{})[0].(map[string]interface{})["description"])
+	}
+}
+
+func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
+	provider := AlertProvider{WebhookURL: "http://example.com"}
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &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 != "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())
+	}
+}

alerting/provider/mattermost/mattermost.go

@@ -4,23 +4,33 @@ import (
 	"fmt"
 	"net/http"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/client"
 	"github.com/TwinProduction/gatus/core"
 )
 
 // AlertProvider is the configuration necessary for sending an alert using Mattermost
 type AlertProvider struct {
 	WebhookURL string `yaml:"webhook-url"`
-	Insecure   bool   `yaml:"insecure,omitempty"`
+
+	// ClientConfig is the configuration of the client used to communicate with the provider's target
+	ClientConfig *client.Config `yaml:"client"`
+
+	// DefaultAlert is the default alert configuration to use for services with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert"`
 }
 
 // IsValid returns whether the provider's configuration is valid
 func (provider *AlertProvider) IsValid() bool {
+	if provider.ClientConfig == nil {
+		provider.ClientConfig = client.GetDefaultConfig()
+	}
 	return len(provider.WebhookURL) > 0
 }
 
 // ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *core.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
 	var message string
 	var color string
 	if resolved {
@@ -38,12 +48,16 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
 		} else {
 			prefix = ":x:"
 		}
-		results += fmt.Sprintf("%s - `%s`\n", prefix, conditionResult.Condition)
+		results += fmt.Sprintf("%s - `%s`\\n", prefix, conditionResult.Condition)
+	}
+	var description string
+	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
+		description = ":\\n> " + alertDescription
 	}
 	return &custom.AlertProvider{
-		URL:      provider.WebhookURL,
-		Method:   http.MethodPost,
-		Insecure: provider.Insecure,
+		URL:          provider.WebhookURL,
+		Method:       http.MethodPost,
+		ClientConfig: provider.ClientConfig,
 		Body: fmt.Sprintf(`{
   "text": "",
   "username": "gatus",
@@ -52,7 +66,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
     {
       "title": ":rescue_worker_helmet: Gatus",
       "fallback": "Gatus - %s",
-      "text": "%s:\n> %s",
+      "text": "%s%s",
       "short": false,
       "color": "%s",
       "fields": [
@@ -69,7 +83,12 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
       ]
     }
   ]
-}`, message, message, alert.Description, color, service.URL, results),
+}`, message, message, description, color, service.URL, results),
 		Headers: map[string]string{"Content-Type": "application/json"},
 	}
 }
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/mattermost/mattermost_test.go

@@ -1,9 +1,12 @@
 package mattermost
 
 import (
+	"encoding/json"
+	"net/http"
 	"strings"
 	"testing"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/core"
 )
 
@@ -19,23 +22,49 @@ func TestAlertProvider_IsValid(t *testing.T) {
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.com"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
+	provider := AlertProvider{WebhookURL: "http://example.org"}
+	alertDescription := "test"
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{Name: "svc"}, &alert.Alert{Description: &alertDescription}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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 != "http://example.org" {
+		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
+	if expected := "An alert for *svc* has been resolved after passing successfully 0 time(s) in a row:\n> test"; expected != body["attachments"].([]interface{})[0].(map[string]interface{})["text"] {
+		t.Errorf("expected $.attachments[0].description to be %s, got %s", expected, body["attachments"].([]interface{})[0].(map[string]interface{})["text"])
+	}
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.com"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
+	provider := AlertProvider{WebhookURL: "http://example.org"}
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &alert.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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 != "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())
+	}
 }

alerting/provider/messagebird/messagebird.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"net/http"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/alerting/provider/custom"
 	"github.com/TwinProduction/gatus/core"
 )
@@ -17,6 +18,9 @@ type AlertProvider struct {
 	AccessKey  string `yaml:"access-key"`
 	Originator string `yaml:"originator"`
 	Recipients string `yaml:"recipients"`
+
+	// DefaultAlert is the default alert configuration to use for services with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -26,12 +30,12 @@ func (provider *AlertProvider) IsValid() bool {
 
 // 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(service *core.Service, alert *core.Alert, _ *core.Result, resolved bool) *custom.AlertProvider {
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *alert.Alert, _ *core.Result, resolved bool) *custom.AlertProvider {
 	var message string
 	if resolved {
-		message = fmt.Sprintf("RESOLVED: %s - %s", service.Name, alert.Description)
+		message = fmt.Sprintf("RESOLVED: %s - %s", service.Name, alert.GetDescription())
 	} else {
-		message = fmt.Sprintf("TRIGGERED: %s - %s", service.Name, alert.Description)
+		message = fmt.Sprintf("TRIGGERED: %s - %s", service.Name, alert.GetDescription())
 	}
 
 	return &custom.AlertProvider{
@@ -48,3 +52,8 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
 		},
 	}
 }
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/messagebird/messagebird_test.go

@@ -1,9 +1,12 @@
 package messagebird
 
 import (
+	"encoding/json"
+	"net/http"
 	"strings"
 	"testing"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/core"
 )
 
@@ -28,13 +31,24 @@ func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
 		Originator: "1",
 		Recipients: "1",
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, true)
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &alert.Alert{}, &core.Result{}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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())
+	}
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
@@ -43,11 +57,22 @@ func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
 		Originator: "1",
 		Recipients: "1",
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, false)
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &alert.Alert{}, &core.Result{}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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())
+	}
 }

alerting/provider/pagerduty/pagerduty.go

@@ -4,13 +4,21 @@ import (
 	"fmt"
 	"net/http"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/alerting/provider/custom"
 	"github.com/TwinProduction/gatus/core"
 )
 
+const (
+	restAPIURL = "https://events.pagerduty.com/v2/enqueue"
+)
+
 // AlertProvider is the configuration necessary for sending an alert using PagerDuty
 type AlertProvider struct {
 	IntegrationKey string `yaml:"integration-key"`
+
+	// DefaultAlert is the default alert configuration to use for services with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -21,19 +29,19 @@ func (provider *AlertProvider) IsValid() bool {
 // ToCustomAlertProvider converts the provider into a custom.AlertProvider
 //
 // relevant: https://developer.pagerduty.com/docs/events-api-v2/trigger-events/
-func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *core.Alert, _ *core.Result, resolved bool) *custom.AlertProvider {
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *alert.Alert, _ *core.Result, resolved bool) *custom.AlertProvider {
 	var message, eventAction, resolveKey string
 	if resolved {
-		message = fmt.Sprintf("RESOLVED: %s - %s", service.Name, alert.Description)
+		message = fmt.Sprintf("RESOLVED: %s - %s", service.Name, alert.GetDescription())
 		eventAction = "resolve"
 		resolveKey = alert.ResolveKey
 	} else {
-		message = fmt.Sprintf("TRIGGERED: %s - %s", service.Name, alert.Description)
+		message = fmt.Sprintf("TRIGGERED: %s - %s", service.Name, alert.GetDescription())
 		eventAction = "trigger"
 		resolveKey = ""
 	}
 	return &custom.AlertProvider{
-		URL:    "https://events.pagerduty.com/v2/enqueue",
+		URL:    restAPIURL,
 		Method: http.MethodPost,
 		Body: fmt.Sprintf(`{
   "routing_key": "%s",
@@ -50,3 +58,8 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
 		},
 	}
 }
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/pagerduty/pagerduty_test.go

@@ -1,9 +1,12 @@
 package pagerduty
 
 import (
+	"encoding/json"
+	"net/http"
 	"strings"
 	"testing"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/core"
 )
 
@@ -20,22 +23,44 @@ func TestAlertProvider_IsValid(t *testing.T) {
 
 func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
 	provider := AlertProvider{IntegrationKey: "00000000000000000000000000000000"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, true)
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &alert.Alert{}, &core.Result{}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
 	provider := AlertProvider{IntegrationKey: "00000000000000000000000000000000"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, false)
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &alert.Alert{}, &core.Result{}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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())
+	}
 }

alerting/provider/provider.go

@@ -1,11 +1,15 @@
 package provider
 
 import (
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/alerting/provider/discord"
 	"github.com/TwinProduction/gatus/alerting/provider/mattermost"
 	"github.com/TwinProduction/gatus/alerting/provider/messagebird"
 	"github.com/TwinProduction/gatus/alerting/provider/pagerduty"
 	"github.com/TwinProduction/gatus/alerting/provider/slack"
+	"github.com/TwinProduction/gatus/alerting/provider/teams"
+	"github.com/TwinProduction/gatus/alerting/provider/telegram"
 	"github.com/TwinProduction/gatus/alerting/provider/twilio"
 	"github.com/TwinProduction/gatus/core"
 )
@@ -16,15 +20,43 @@ type AlertProvider interface {
 	IsValid() bool
 
 	// ToCustomAlertProvider converts the provider into a custom.AlertProvider
-	ToCustomAlertProvider(service *core.Service, alert *core.Alert, result *core.Result, resolved bool) *custom.AlertProvider
+	ToCustomAlertProvider(service *core.Service, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider
+
+	// GetDefaultAlert returns the provider's default alert configuration
+	GetDefaultAlert() *alert.Alert
+}
+
+// ParseWithDefaultAlert parses a service alert by using the provider's default alert as a baseline
+func ParseWithDefaultAlert(providerDefaultAlert, serviceAlert *alert.Alert) {
+	if providerDefaultAlert == nil || serviceAlert == nil {
+		return
+	}
+	if serviceAlert.Enabled == nil {
+		serviceAlert.Enabled = providerDefaultAlert.Enabled
+	}
+	if serviceAlert.SendOnResolved == nil {
+		serviceAlert.SendOnResolved = providerDefaultAlert.SendOnResolved
+	}
+	if serviceAlert.Description == nil {
+		serviceAlert.Description = providerDefaultAlert.Description
+	}
+	if serviceAlert.FailureThreshold == 0 {
+		serviceAlert.FailureThreshold = providerDefaultAlert.FailureThreshold
+	}
+	if serviceAlert.SuccessThreshold == 0 {
+		serviceAlert.SuccessThreshold = providerDefaultAlert.SuccessThreshold
+	}
 }
 
 var (
 	// Validate interface implementation on compile
 	_ AlertProvider = (*custom.AlertProvider)(nil)
-	_ AlertProvider = (*twilio.AlertProvider)(nil)
-	_ AlertProvider = (*slack.AlertProvider)(nil)
+	_ AlertProvider = (*discord.AlertProvider)(nil)
 	_ AlertProvider = (*mattermost.AlertProvider)(nil)
 	_ AlertProvider = (*messagebird.AlertProvider)(nil)
 	_ AlertProvider = (*pagerduty.AlertProvider)(nil)
+	_ AlertProvider = (*slack.AlertProvider)(nil)
+	_ AlertProvider = (*teams.AlertProvider)(nil)
+	_ AlertProvider = (*telegram.AlertProvider)(nil)
+	_ AlertProvider = (*twilio.AlertProvider)(nil)
 )

alerting/provider/provider_test.go

@@ -0,0 +1,153 @@
+package provider
+
+import (
+	"testing"
+
+	"github.com/TwinProduction/gatus/alerting/alert"
+)
+
+func TestParseWithDefaultAlert(t *testing.T) {
+	type Scenario struct {
+		Name                                            string
+		DefaultAlert, ServiceAlert, ExpectedOutputAlert *alert.Alert
+	}
+	enabled := true
+	disabled := false
+	firstDescription := "description-1"
+	secondDescription := "description-2"
+	scenarios := []Scenario{
+		{
+			Name: "service-alert-type-only",
+			DefaultAlert: &alert.Alert{
+				Enabled:          &enabled,
+				SendOnResolved:   &enabled,
+				Description:      &firstDescription,
+				FailureThreshold: 5,
+				SuccessThreshold: 10,
+			},
+			ServiceAlert: &alert.Alert{
+				Type: alert.TypeDiscord,
+			},
+			ExpectedOutputAlert: &alert.Alert{
+				Type:             alert.TypeDiscord,
+				Enabled:          &enabled,
+				SendOnResolved:   &enabled,
+				Description:      &firstDescription,
+				FailureThreshold: 5,
+				SuccessThreshold: 10,
+			},
+		},
+		{
+			Name: "service-alert-overwrites-default-alert",
+			DefaultAlert: &alert.Alert{
+				Enabled:          &disabled,
+				SendOnResolved:   &disabled,
+				Description:      &firstDescription,
+				FailureThreshold: 5,
+				SuccessThreshold: 10,
+			},
+			ServiceAlert: &alert.Alert{
+				Type:             alert.TypeTelegram,
+				Enabled:          &enabled,
+				SendOnResolved:   &enabled,
+				Description:      &secondDescription,
+				FailureThreshold: 6,
+				SuccessThreshold: 11,
+			},
+			ExpectedOutputAlert: &alert.Alert{
+				Type:             alert.TypeTelegram,
+				Enabled:          &enabled,
+				SendOnResolved:   &enabled,
+				Description:      &secondDescription,
+				FailureThreshold: 6,
+				SuccessThreshold: 11,
+			},
+		},
+		{
+			Name: "service-alert-partially-overwrites-default-alert",
+			DefaultAlert: &alert.Alert{
+				Enabled:          &enabled,
+				SendOnResolved:   &enabled,
+				Description:      &firstDescription,
+				FailureThreshold: 5,
+				SuccessThreshold: 10,
+			},
+			ServiceAlert: &alert.Alert{
+				Type:             alert.TypeDiscord,
+				Enabled:          nil,
+				SendOnResolved:   nil,
+				FailureThreshold: 6,
+				SuccessThreshold: 11,
+			},
+			ExpectedOutputAlert: &alert.Alert{
+				Type:             alert.TypeDiscord,
+				Enabled:          &enabled,
+				SendOnResolved:   &enabled,
+				Description:      &firstDescription,
+				FailureThreshold: 6,
+				SuccessThreshold: 11,
+			},
+		},
+		{
+			Name: "default-alert-type-should-be-ignored",
+			DefaultAlert: &alert.Alert{
+				Type:             alert.TypeTelegram,
+				Enabled:          &enabled,
+				SendOnResolved:   &enabled,
+				Description:      &firstDescription,
+				FailureThreshold: 5,
+				SuccessThreshold: 10,
+			},
+			ServiceAlert: &alert.Alert{
+				Type: alert.TypeDiscord,
+			},
+			ExpectedOutputAlert: &alert.Alert{
+				Type:             alert.TypeDiscord,
+				Enabled:          &enabled,
+				SendOnResolved:   &enabled,
+				Description:      &firstDescription,
+				FailureThreshold: 5,
+				SuccessThreshold: 10,
+			},
+		},
+		{
+			Name: "no-default-alert",
+			DefaultAlert: &alert.Alert{
+				Type:             alert.TypeDiscord,
+				Enabled:          nil,
+				SendOnResolved:   nil,
+				Description:      &firstDescription,
+				FailureThreshold: 2,
+				SuccessThreshold: 5,
+			},
+			ServiceAlert:        nil,
+			ExpectedOutputAlert: nil,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			ParseWithDefaultAlert(scenario.DefaultAlert, scenario.ServiceAlert)
+			if scenario.ExpectedOutputAlert == nil {
+				if scenario.ServiceAlert != nil {
+					t.Fail()
+				}
+				return
+			}
+			if scenario.ServiceAlert.IsEnabled() != scenario.ExpectedOutputAlert.IsEnabled() {
+				t.Errorf("expected ServiceAlert.IsEnabled() to be %v, got %v", scenario.ExpectedOutputAlert.IsEnabled(), scenario.ServiceAlert.IsEnabled())
+			}
+			if scenario.ServiceAlert.IsSendingOnResolved() != scenario.ExpectedOutputAlert.IsSendingOnResolved() {
+				t.Errorf("expected ServiceAlert.IsSendingOnResolved() to be %v, got %v", scenario.ExpectedOutputAlert.IsSendingOnResolved(), scenario.ServiceAlert.IsSendingOnResolved())
+			}
+			if scenario.ServiceAlert.GetDescription() != scenario.ExpectedOutputAlert.GetDescription() {
+				t.Errorf("expected ServiceAlert.GetDescription() to be %v, got %v", scenario.ExpectedOutputAlert.GetDescription(), scenario.ServiceAlert.GetDescription())
+			}
+			if scenario.ServiceAlert.FailureThreshold != scenario.ExpectedOutputAlert.FailureThreshold {
+				t.Errorf("expected ServiceAlert.FailureThreshold to be %v, got %v", scenario.ExpectedOutputAlert.FailureThreshold, scenario.ServiceAlert.FailureThreshold)
+			}
+			if scenario.ServiceAlert.SuccessThreshold != scenario.ExpectedOutputAlert.SuccessThreshold {
+				t.Errorf("expected ServiceAlert.SuccessThreshold to be %v, got %v", scenario.ExpectedOutputAlert.SuccessThreshold, scenario.ServiceAlert.SuccessThreshold)
+			}
+		})
+	}
+}

alerting/provider/slack/slack.go

@@ -4,13 +4,17 @@ import (
 	"fmt"
 	"net/http"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/alerting/provider/custom"
 	"github.com/TwinProduction/gatus/core"
 )
 
 // AlertProvider is the configuration necessary for sending an alert using Slack
 type AlertProvider struct {
-	WebhookURL string `yaml:"webhook-url"`
+	WebhookURL string `yaml:"webhook-url"` // Slack webhook URL
+
+	// DefaultAlert is the default alert configuration to use for services with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -19,7 +23,7 @@ func (provider *AlertProvider) IsValid() bool {
 }
 
 // ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *core.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
 	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", service.Name, alert.SuccessThreshold)
@@ -35,7 +39,11 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
 		} else {
 			prefix = ":x:"
 		}
-		results += fmt.Sprintf("%s - `%s`\n", prefix, conditionResult.Condition)
+		results += fmt.Sprintf("%s - `%s`\\n", prefix, conditionResult.Condition)
+	}
+	var description string
+	if alertDescription := alert.GetDescription(); len(alertDescription) > 0 {
+		description = ":\\n> " + alertDescription
 	}
 	return &custom.AlertProvider{
 		URL:    provider.WebhookURL,
@@ -45,7 +53,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
   "attachments": [
     {
       "title": ":helmet_with_white_cross: Gatus",
-      "text": "%s:\n> %s",
+      "text": "%s%s",
       "short": false,
       "color": "%s",
       "fields": [
@@ -57,7 +65,12 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
       ]
     }
   ]
-}`, message, alert.Description, color, results),
+}`, message, description, color, results),
 		Headers: map[string]string{"Content-Type": "application/json"},
 	}
 }
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/slack/slack_test.go

@@ -1,9 +1,12 @@
 package slack
 
 import (
+	"encoding/json"
+	"net/http"
 	"strings"
 	"testing"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/core"
 )
 
@@ -20,22 +23,48 @@ func TestAlertProvider_IsValid(t *testing.T) {
 
 func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
 	provider := AlertProvider{WebhookURL: "http://example.com"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
+	alertDescription := "test"
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{Name: "svc"}, &alert.Alert{Description: &alertDescription}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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 != "http://example.com" {
+		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
+	if expected := "An alert for *svc* has been resolved after passing successfully 0 time(s) in a row:\n> test"; expected != body["attachments"].([]interface{})[0].(map[string]interface{})["text"] {
+		t.Errorf("expected $.attachments[0].description to be %s, got %s", expected, body["attachments"].([]interface{})[0].(map[string]interface{})["text"])
+	}
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
 	provider := AlertProvider{WebhookURL: "http://example.com"}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &alert.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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 != "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())
+	}
 }

alerting/provider/teams/teams.go

@@ -0,0 +1,77 @@
+package teams
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/TwinProduction/gatus/alerting/alert"
+	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/core"
+)
+
+// AlertProvider is the configuration necessary for sending an alert using Teams
+type AlertProvider struct {
+	WebhookURL string `yaml:"webhook-url"`
+
+	// DefaultAlert is the default alert configuration to use for services with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert"`
+}
+
+// IsValid returns whether the provider's configuration is valid
+func (provider *AlertProvider) IsValid() bool {
+	return len(provider.WebhookURL) > 0
+}
+
+// ToCustomAlertProvider converts the provider into a custom.AlertProvider
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
+	var message string
+	var color string
+	if resolved {
+		message = fmt.Sprintf("An alert for *%s* has been resolved after passing successfully %d time(s) in a row", service.Name, 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", service.Name, alert.FailureThreshold)
+		color = "#DD0000"
+	}
+	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 = ":\\n> " + alertDescription
+	}
+	return &custom.AlertProvider{
+		URL:    provider.WebhookURL,
+		Method: http.MethodPost,
+		Body: fmt.Sprintf(`{
+  "@type": "MessageCard",
+  "@context": "http://schema.org/extensions",
+  "themeColor": "%s",
+  "title": "&#x1F6A8; Gatus",
+  "text": "%s%s",
+  "sections": [
+    {
+      "activityTitle": "URL",
+      "text": "%s"
+    },
+    {
+      "activityTitle": "Condition results",
+      "text": "%s"
+    }
+  ]
+}`, color, message, description, service.URL, results),
+		Headers: map[string]string{"Content-Type": "application/json"},
+	}
+}
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/teams/teams_test.go

@@ -0,0 +1,70 @@
+package teams
+
+import (
+	"encoding/json"
+	"net/http"
+	"strings"
+	"testing"
+
+	"github.com/TwinProduction/gatus/alerting/alert"
+	"github.com/TwinProduction/gatus/core"
+)
+
+func TestAlertProvider_IsValid(t *testing.T) {
+	invalidProvider := AlertProvider{WebhookURL: ""}
+	if invalidProvider.IsValid() {
+		t.Error("provider shouldn't have been valid")
+	}
+	validProvider := AlertProvider{WebhookURL: "http://example.com"}
+	if !validProvider.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
+func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
+	provider := AlertProvider{WebhookURL: "http://example.org"}
+	alertDescription := "test"
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{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")
+	}
+	if !strings.Contains(customAlertProvider.Body, "resolved") {
+		t.Error("customAlertProvider.Body should've contained the substring resolved")
+	}
+	if customAlertProvider.URL != "http://example.org" {
+		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
+	if expected := "An alert for *svc* has been resolved after passing successfully 0 time(s) in a row:\n> test"; expected != body["text"] {
+		t.Errorf("expected $.text to be %s, got %s", expected, body["text"])
+	}
+}
+
+func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
+	provider := AlertProvider{WebhookURL: "http://example.org"}
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &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 != "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())
+	}
+}

alerting/provider/telegram/telegram.go

@@ -0,0 +1,60 @@
+package telegram
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/TwinProduction/gatus/alerting/alert"
+	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/core"
+)
+
+// AlertProvider is the configuration necessary for sending an alert using Telegram
+type AlertProvider struct {
+	Token string `yaml:"token"`
+	ID    string `yaml:"id"`
+
+	// DefaultAlert is the default alert configuration to use for services with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert"`
+}
+
+// IsValid returns whether the provider's configuration is valid
+func (provider *AlertProvider) IsValid() bool {
+	return len(provider.Token) > 0 && len(provider.ID) > 0
+}
+
+// ToCustomAlertProvider converts the provider into a custom.AlertProvider
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *alert.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
+	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—  ", service.Name, alert.FailureThreshold)
+	} else {
+		message = fmt.Sprintf("An alert for *%s* has been triggered:\\n—\\n    _healthcheck failed %d time(s) in a row_\\n—  ", service.Name, 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 text string
+	if len(alert.GetDescription()) > 0 {
+		text = fmt.Sprintf("⛑ *Gatus* \\n%s \\n*Description* \\n_%s_  \\n\\n*Condition results*\\n%s", message, alert.GetDescription(), results)
+	} 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"},
+	}
+}
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/telegram/telegram_test.go

@@ -0,0 +1,91 @@
+package telegram
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strings"
+	"testing"
+
+	"github.com/TwinProduction/gatus/alerting/alert"
+	"github.com/TwinProduction/gatus/core"
+)
+
+func TestAlertProvider_IsValid(t *testing.T) {
+	invalidProvider := AlertProvider{Token: "", ID: ""}
+	if invalidProvider.IsValid() {
+		t.Error("provider shouldn't have been valid")
+	}
+	validProvider := AlertProvider{Token: "123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11", ID: "12345678"}
+	if !validProvider.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
+func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
+	provider := AlertProvider{Token: "123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11", ID: "12345678"}
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &alert.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, 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 != 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())
+	}
+}
+
+func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
+	provider := AlertProvider{Token: "123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11", ID: "0123456789"}
+	description := "Healthcheck Successful"
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &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")
+	}
+	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.Service{}, &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())
+	}
+}

alerting/provider/twilio/twilio.go

@@ -6,6 +6,7 @@ import (
 	"net/http"
 	"net/url"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/alerting/provider/custom"
 	"github.com/TwinProduction/gatus/core"
 )
@@ -16,6 +17,9 @@ type AlertProvider struct {
 	Token string `yaml:"token"`
 	From  string `yaml:"from"`
 	To    string `yaml:"to"`
+
+	// DefaultAlert is the default alert configuration to use for services with an alert of the appropriate type
+	DefaultAlert *alert.Alert `yaml:"default-alert"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -24,12 +28,12 @@ func (provider *AlertProvider) IsValid() bool {
 }
 
 // ToCustomAlertProvider converts the provider into a custom.AlertProvider
-func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *core.Alert, _ *core.Result, resolved bool) *custom.AlertProvider {
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *alert.Alert, _ *core.Result, resolved bool) *custom.AlertProvider {
 	var message string
 	if resolved {
-		message = fmt.Sprintf("RESOLVED: %s - %s", service.Name, alert.Description)
+		message = fmt.Sprintf("RESOLVED: %s - %s", service.Name, alert.GetDescription())
 	} else {
-		message = fmt.Sprintf("TRIGGERED: %s - %s", service.Name, alert.Description)
+		message = fmt.Sprintf("TRIGGERED: %s - %s", service.Name, alert.GetDescription())
 	}
 	return &custom.AlertProvider{
 		URL:    fmt.Sprintf("https://api.twilio.com/2010-04-01/Accounts/%s/Messages.json", provider.SID),
@@ -45,3 +49,8 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
 		},
 	}
 }
+
+// GetDefaultAlert returns the provider's default alert configuration
+func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
+	return provider.DefaultAlert
+}

alerting/provider/twilio/twilio_test.go

@@ -1,9 +1,11 @@
 package twilio
 
 import (
+	"net/http"
 	"strings"
 	"testing"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/core"
 )
 
@@ -26,31 +28,51 @@ func TestTwilioAlertProvider_IsValid(t *testing.T) {
 func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
 	provider := AlertProvider{
 		SID:   "1",
-		Token: "1",
-		From:  "1",
-		To:    "1",
+		Token: "2",
+		From:  "3",
+		To:    "4",
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, true)
+	description := "alert-description"
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{Name: "service-name"}, &alert.Alert{Description: &description}, &core.Result{}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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+service-name+-+alert-description&From=3&To=4" {
+		t.Errorf("expected body to be %s, got %s", "Body=RESOLVED%3A+service-name+-+alert-description&From=3&To=4", customAlertProvider.Body)
+	}
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
 	provider := AlertProvider{
-		SID:   "1",
-		Token: "1",
-		From:  "1",
+		SID:   "4",
+		Token: "3",
+		From:  "2",
 		To:    "1",
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, false)
+	description := "alert-description"
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{Name: "service-name"}, &alert.Alert{Description: &description}, &core.Result{}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been 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+service-name+-+alert-description&From=2&To=1" {
+		t.Errorf("expected body to be %s, got %s", "Body=TRIGGERED%3A+service-name+-+alert-description&From=2&To=1", customAlertProvider.Body)
+	}
 }

client/client.go

@@ -2,54 +2,29 @@ package client
 
 import (
 	"crypto/tls"
+	"crypto/x509"
+	"errors"
 	"net"
 	"net/http"
+	"net/smtp"
+	"runtime"
+	"strings"
 	"time"
 
 	"github.com/go-ping/ping"
 )
 
-var (
-	secureHTTPClient   *http.Client
-	insecureHTTPClient *http.Client
-
-	// pingTimeout is the timeout for the Ping function
-	// This is mainly exposed for testing purposes
-	pingTimeout = 5 * time.Second
-)
-
 // GetHTTPClient returns the shared HTTP client
-func GetHTTPClient(insecure bool) *http.Client {
-	if insecure {
-		if insecureHTTPClient == nil {
-			insecureHTTPClient = &http.Client{
-				Timeout: 10 * time.Second,
-				Transport: &http.Transport{
-					MaxIdleConns:        100,
-					MaxIdleConnsPerHost: 20,
-					TLSClientConfig: &tls.Config{
-						InsecureSkipVerify: true,
-					},
-				},
-			}
-		}
-		return insecureHTTPClient
+func GetHTTPClient(config *Config) *http.Client {
+	if config == nil {
+		return defaultConfig.getHTTPClient()
 	}
-	if secureHTTPClient == nil {
-		secureHTTPClient = &http.Client{
-			Timeout: 10 * time.Second,
-			Transport: &http.Transport{
-				MaxIdleConns:        100,
-				MaxIdleConnsPerHost: 20,
-			},
-		}
-	}
-	return secureHTTPClient
+	return config.getHTTPClient()
 }
 
 // CanCreateTCPConnection checks whether a connection can be established with a TCP service
-func CanCreateTCPConnection(address string) bool {
-	conn, err := net.DialTimeout("tcp", address, 5*time.Second)
+func CanCreateTCPConnection(address string, config *Config) bool {
+	conn, err := net.DialTimeout("tcp", address, config.Timeout)
 	if err != nil {
 		return false
 	}
@@ -57,18 +32,44 @@ func CanCreateTCPConnection(address string) bool {
 	return true
 }
 
+// CanPerformStartTLS checks whether a connection can be established to an address using the STARTTLS protocol
+func CanPerformStartTLS(address string, config *Config) (connected bool, certificate *x509.Certificate, err error) {
+	hostAndPort := strings.Split(address, ":")
+	if len(hostAndPort) != 2 {
+		return false, nil, errors.New("invalid address for starttls, format must be host:port")
+	}
+	smtpClient, err := smtp.Dial(address)
+	if err != nil {
+		return
+	}
+	err = smtpClient.StartTLS(&tls.Config{
+		InsecureSkipVerify: config.Insecure,
+		ServerName:         hostAndPort[0],
+	})
+	if err != nil {
+		return
+	}
+	if state, ok := smtpClient.TLSConnectionState(); ok {
+		certificate = state.PeerCertificates[0]
+	} else {
+		return false, nil, errors.New("could not get TLS connection state")
+	}
+	return true, certificate, nil
+}
+
 // Ping checks if an address can be pinged and returns the round-trip time if the address can be pinged
 //
 // Note that this function takes at least 100ms, even if the address is 127.0.0.1
-func Ping(address string) (bool, time.Duration) {
+func Ping(address string, config *Config) (bool, time.Duration) {
 	pinger, err := ping.NewPinger(address)
 	if err != nil {
 		return false, 0
 	}
 	pinger.Count = 1
-	pinger.Timeout = pingTimeout
-	pinger.SetNetwork("ip4")
-	pinger.SetPrivileged(true)
+	pinger.Timeout = config.Timeout
+	// Set the pinger's privileged mode to true for every operating system except darwin
+	// https://github.com/TwinProduction/gatus/issues/132
+	pinger.SetPrivileged(runtime.GOOS != "darwin")
 	err = pinger.Run()
 	if err != nil {
 		return false, 0

client/client_test.go

@@ -6,46 +6,93 @@ import (
 )
 
 func TestGetHTTPClient(t *testing.T) {
-	if secureHTTPClient != nil {
-		t.Error("secureHTTPClient should've been nil since it hasn't been called a single time yet")
+	cfg := &Config{
+		Insecure:       false,
+		IgnoreRedirect: false,
+		Timeout:        0,
 	}
-	if insecureHTTPClient != nil {
-		t.Error("insecureHTTPClient should've been nil since it hasn't been called a single time yet")
+	cfg.ValidateAndSetDefaults()
+	if GetHTTPClient(cfg) == nil {
+		t.Error("expected client to not be nil")
 	}
-	_ = GetHTTPClient(false)
-	if secureHTTPClient == nil {
-		t.Error("secureHTTPClient shouldn't have been nil, since it has been called once")
-	}
-	if insecureHTTPClient != nil {
-		t.Error("insecureHTTPClient should've been nil since it hasn't been called a single time yet")
-	}
-	_ = GetHTTPClient(true)
-	if secureHTTPClient == nil {
-		t.Error("secureHTTPClient shouldn't have been nil, since it has been called once")
-	}
-	if insecureHTTPClient == nil {
-		t.Error("insecureHTTPClient shouldn't have been nil, since it has been called once")
+	if GetHTTPClient(nil) == nil {
+		t.Error("expected client to not be nil")
 	}
 }
 
 func TestPing(t *testing.T) {
-	pingTimeout = 500 * time.Millisecond
-	if success, rtt := Ping("127.0.0.1"); !success {
+	if success, rtt := Ping("127.0.0.1", &Config{Timeout: 500 * time.Millisecond}); !success {
 		t.Error("expected true")
 		if rtt == 0 {
 			t.Error("Round-trip time returned on success should've higher than 0")
 		}
 	}
-	if success, rtt := Ping("256.256.256.256"); success {
+	if success, rtt := Ping("256.256.256.256", &Config{Timeout: 500 * time.Millisecond}); success {
 		t.Error("expected false, because the IP is invalid")
 		if rtt != 0 {
 			t.Error("Round-trip time returned on failure should've been 0")
 		}
 	}
-	if success, rtt := Ping("192.168.152.153"); success {
+	if success, rtt := Ping("192.168.152.153", &Config{Timeout: 500 * time.Millisecond}); success {
 		t.Error("expected false, because the IP is valid but the host should be unreachable")
 		if rtt != 0 {
 			t.Error("Round-trip time returned on failure should've been 0")
 		}
 	}
 }
+
+func TestCanPerformStartTLS(t *testing.T) {
+	type args struct {
+		address  string
+		insecure bool
+	}
+	tests := []struct {
+		name          string
+		args          args
+		wantConnected bool
+		wantErr       bool
+	}{
+		{
+			name: "invalid address",
+			args: args{
+				address: "test",
+			},
+			wantConnected: false,
+			wantErr:       true,
+		},
+		{
+			name: "error dial",
+			args: args{
+				address: "test:1234",
+			},
+			wantConnected: false,
+			wantErr:       true,
+		},
+		{
+			name: "valid starttls",
+			args: args{
+				address: "smtp.gmail.com:587",
+			},
+			wantConnected: true,
+			wantErr:       false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			connected, _, err := CanPerformStartTLS(tt.args.address, &Config{Insecure: tt.args.insecure, Timeout: 5 * time.Second})
+			if (err != nil) != tt.wantErr {
+				t.Errorf("CanPerformStartTLS() err=%v, wantErr=%v", err, tt.wantErr)
+				return
+			}
+			if connected != tt.wantConnected {
+				t.Errorf("CanPerformStartTLS() connected=%v, wantConnected=%v", connected, tt.wantConnected)
+			}
+		})
+	}
+}
+
+func TestCanCreateTCPConnection(t *testing.T) {
+	if CanCreateTCPConnection("127.0.0.1", &Config{Timeout: 5 * time.Second}) {
+		t.Error("should've failed, because there's no port in the address")
+	}
+}

client/config.go

@@ -0,0 +1,73 @@
+package client
+
+import (
+	"crypto/tls"
+	"net/http"
+	"time"
+)
+
+const (
+	defaultHTTPTimeout = 10 * time.Second
+)
+
+var (
+	// DefaultConfig is the default client configuration
+	defaultConfig = Config{
+		Insecure:       false,
+		IgnoreRedirect: false,
+		Timeout:        defaultHTTPTimeout,
+	}
+)
+
+// GetDefaultConfig returns a copy of the default configuration
+func GetDefaultConfig() *Config {
+	cfg := defaultConfig
+	return &cfg
+}
+
+// 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"`
+
+	// IgnoreRedirect determines whether to ignore redirects (true) or follow them (false, default)
+	IgnoreRedirect bool `yaml:"ignore-redirect"`
+
+	// Timeout for the client
+	Timeout time.Duration `yaml:"timeout"`
+
+	httpClient *http.Client
+}
+
+// ValidateAndSetDefaults validates the client configuration and sets the default values if necessary
+func (c *Config) ValidateAndSetDefaults() {
+	if c.Timeout < time.Millisecond {
+		c.Timeout = 10 * time.Second
+	}
+}
+
+// GetHTTPClient return a HTTP client matching the Config's parameters.
+func (c *Config) getHTTPClient() *http.Client {
+	if c.httpClient == nil {
+		c.httpClient = &http.Client{
+			Timeout: c.Timeout,
+			Transport: &http.Transport{
+				MaxIdleConns:        100,
+				MaxIdleConnsPerHost: 20,
+				Proxy:               http.ProxyFromEnvironment,
+				TLSClientConfig: &tls.Config{
+					InsecureSkipVerify: c.Insecure,
+				},
+			},
+			CheckRedirect: func(req *http.Request, via []*http.Request) error {
+				if c.IgnoreRedirect {
+					// Don't follow redirects
+					return http.ErrUseLastResponse
+				}
+				// Follow redirects
+				return nil
+			},
+		}
+	}
+	return c.httpClient
+}

client/config_test.go

@@ -0,0 +1,37 @@
+package client
+
+import (
+	"net/http"
+	"testing"
+	"time"
+)
+
+func TestConfig_getHTTPClient(t *testing.T) {
+	insecureConfig := &Config{Insecure: true}
+	insecureConfig.ValidateAndSetDefaults()
+	insecureClient := insecureConfig.getHTTPClient()
+	if !(insecureClient.Transport).(*http.Transport).TLSClientConfig.InsecureSkipVerify {
+		t.Error("expected Config.Insecure set to true to cause the HTTP client to skip certificate verification")
+	}
+	if insecureClient.Timeout != defaultHTTPTimeout {
+		t.Error("expected Config.Timeout to default the HTTP client to a timeout of 10s")
+	}
+	request, _ := http.NewRequest("GET", "", nil)
+	if err := insecureClient.CheckRedirect(request, nil); err != nil {
+		t.Error("expected Config.IgnoreRedirect set to false to cause the HTTP client's CheckRedirect to return nil")
+	}
+
+	secureConfig := &Config{IgnoreRedirect: true, Timeout: 5 * time.Second}
+	secureConfig.ValidateAndSetDefaults()
+	secureClient := secureConfig.getHTTPClient()
+	if (secureClient.Transport).(*http.Transport).TLSClientConfig.InsecureSkipVerify {
+		t.Error("expected Config.Insecure set to false to cause the HTTP client to not skip certificate verification")
+	}
+	if secureClient.Timeout != 5*time.Second {
+		t.Error("expected Config.Timeout to cause the HTTP client to have a timeout of 5s")
+	}
+	request, _ = http.NewRequest("GET", "", nil)
+	if err := secureClient.CheckRedirect(request, nil); err != http.ErrUseLastResponse {
+		t.Error("expected Config.IgnoreRedirect set to true to cause the HTTP client's CheckRedirect to return http.ErrUseLastResponse")
+	}
+}

config.yaml

@@ -1,23 +1,24 @@
 services:
-  - name: frontend
+  - name: front-end
     group: core
     url: "https://twinnation.org/health"
     interval: 1m
     conditions:
       - "[STATUS] == 200"
       - "[BODY].status == UP"
-      - "[RESPONSE_TIME] < 70"
+      - "[RESPONSE_TIME] < 150"
 
-  - name: backend
+  - name: back-end
     group: core
-    url: "http://example.org/"
+    url: "https://example.org/"
     interval: 5m
     conditions:
       - "[STATUS] == 200"
+      - "[CERTIFICATE_EXPIRATION] > 48h"
 
   - name: monitoring
     group: internal
-    url: "http://example.com/"
+    url: "https://example.org/"
     interval: 5m
     conditions:
       - "[STATUS] == 200"
@@ -29,10 +30,18 @@ services:
     conditions:
       - "[STATUS] == 200"
 
-  - name: cat-fact
-    url: "https://cat-fact.herokuapp.com/facts/random"
+  - name: example-dns-query
+    url: "8.8.8.8" # Address of the DNS server to use
     interval: 5m
+    dns:
+      query-name: "example.com"
+      query-type: "A"
     conditions:
-      - "[STATUS] == 200"
-      - "[BODY].deleted == false"
-      - "len([BODY].text) > 0"
+      - "[BODY] == 93.184.216.34"
+      - "[DNS_RCODE] == NOERROR"
+
+  - name: icmp-ping
+    url: "icmp://example.org"
+    interval: 1m
+    conditions:
+      - "[CONNECTED] == true"

config/config.go

@@ -5,12 +5,14 @@ import (
 	"io/ioutil"
 	"log"
 	"os"
+	"time"
 
 	"github.com/TwinProduction/gatus/alerting"
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/alerting/provider"
 	"github.com/TwinProduction/gatus/core"
-	"github.com/TwinProduction/gatus/k8s"
 	"github.com/TwinProduction/gatus/security"
+	"github.com/TwinProduction/gatus/storage"
 	"gopkg.in/yaml.v2"
 )
 
@@ -28,9 +30,6 @@ const (
 
 	// DefaultPort is the default port the service will listen on
 	DefaultPort = 8080
-
-	// DefaultContextRoot is the default context root of the web application
-	DefaultContextRoot = "/"
 )
 
 var (
@@ -40,13 +39,12 @@ var (
 	// ErrConfigFileNotFound is an error returned when the configuration file could not be found
 	ErrConfigFileNotFound = errors.New("configuration file not found")
 
-	// ErrConfigNotLoaded is an error returned when an attempt to Get() the configuration before loading it is made
-	ErrConfigNotLoaded = errors.New("configuration is nil")
-
 	// ErrInvalidSecurityConfig is an error returned when the security configuration is invalid
 	ErrInvalidSecurityConfig = errors.New("invalid security configuration")
 
-	config *Config
+	// 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"
 )
 
 // Config is the main configuration structure
@@ -57,6 +55,10 @@ type Config struct {
 	// Metrics Whether to expose metrics at /metrics
 	Metrics bool `yaml:"metrics"`
 
+	// 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"`
+
 	// DisableMonitoringLock Whether to disable the monitoring lock
 	// The monitoring lock is what prevents multiple services from being processed at the same time.
 	// Disabling this may lead to inaccurate response times
@@ -71,52 +73,67 @@ type Config struct {
 	// Services List of services to monitor
 	Services []*core.Service `yaml:"services"`
 
-	// Kubernetes is the Kubernetes configuration
-	Kubernetes *k8s.Config `yaml:"kubernetes"`
+	// Storage is the configuration for how the data is stored
+	Storage *storage.Config `yaml:"storage"`
 
 	// Web is the configuration for the web listener
-	Web *webConfig `yaml:"web"`
+	Web *WebConfig `yaml:"web"`
+
+	// UI is the configuration for the UI
+	UI *UIConfig `yaml:"ui"`
+
+	filePath        string    // path to the file from which config was loaded from
+	lastFileModTime time.Time // last modification time
 }
 
-// Get returns the configuration, or panics if the configuration hasn't loaded yet
-func Get() *Config {
-	if config == nil {
-		panic(ErrConfigNotLoaded)
+// 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 {
+	if fileInfo, err := os.Stat(config.filePath); err == nil {
+		if !fileInfo.ModTime().IsZero() {
+			return config.lastFileModTime.Unix() != fileInfo.ModTime().Unix()
+		}
 	}
-	return config
+	return false
 }
 
-// Set sets the configuration
-// Used only for testing
-func Set(cfg *Config) {
-	config = cfg
+// UpdateLastFileModTime refreshes Config.lastFileModTime
+func (config *Config) UpdateLastFileModTime() {
+	if fileInfo, err := os.Stat(config.filePath); err == nil {
+		if !fileInfo.ModTime().IsZero() {
+			config.lastFileModTime = fileInfo.ModTime()
+		}
+	} else {
+		log.Println("[config][UpdateLastFileModTime] Ran into error updating lastFileModTime:", err.Error())
+	}
 }
 
 // Load loads a custom configuration file
 // Note that the misconfiguration of some fields may lead to panics. This is on purpose.
-func Load(configFile string) error {
+func Load(configFile string) (*Config, error) {
 	log.Printf("[config][Load] Reading configuration from configFile=%s", configFile)
 	cfg, err := readConfigurationFile(configFile)
 	if err != nil {
 		if os.IsNotExist(err) {
-			return ErrConfigFileNotFound
+			return nil, ErrConfigFileNotFound
 		}
-		return err
+		return nil, err
 	}
-	config = cfg
-	return nil
+	cfg.filePath = configFile
+	cfg.UpdateLastFileModTime()
+	return cfg, nil
 }
 
 // LoadDefaultConfiguration loads the default configuration file
-func LoadDefaultConfiguration() error {
-	err := Load(DefaultConfigurationFilePath)
+func LoadDefaultConfiguration() (*Config, error) {
+	cfg, err := Load(DefaultConfigurationFilePath)
 	if err != nil {
 		if err == ErrConfigFileNotFound {
 			return Load(DefaultFallbackConfigurationFilePath)
 		}
-		return err
+		return nil, err
 	}
-	return nil
+	return cfg, nil
 }
 
 func readConfigurationFile(fileName string) (config *Config, err error) {
@@ -136,57 +153,88 @@ func parseAndValidateConfigBytes(yamlBytes []byte) (config *Config, err error) {
 	if err != nil {
 		return
 	}
-	// Check if the configuration file at least has services configured or Kubernetes auto discovery enabled
-	if config == nil || ((config.Services == nil || len(config.Services) == 0) && (config.Kubernetes == nil || !config.Kubernetes.AutoDiscover)) {
+	// Check if the configuration file at least has services configured
+	if config == nil || config.Services == nil || len(config.Services) == 0 {
 		err = ErrNoServiceInConfig
 	} else {
 		// Note that the functions below may panic, and this is on purpose to prevent Gatus from starting with
 		// invalid configurations
-		validateAlertingConfig(config)
-		validateSecurityConfig(config)
-		validateServicesConfig(config)
-		validateKubernetesConfig(config)
-		validateWebConfig(config)
+		validateAlertingConfig(config.Alerting, config.Services, config.Debug)
+		if err := validateSecurityConfig(config); err != nil {
+			return nil, err
+		}
+		if err := validateServicesConfig(config); err != nil {
+			return nil, err
+		}
+		if err := validateWebConfig(config); err != nil {
+			return nil, err
+		}
+		if err := validateUIConfig(config); err != nil {
+			return nil, err
+		}
+		if err := validateStorageConfig(config); err != nil {
+			return nil, err
+		}
 	}
 	return
 }
 
-func validateWebConfig(config *Config) {
-	if config.Web == nil {
-		config.Web = &webConfig{Address: DefaultAddress, Port: DefaultPort, ContextRoot: DefaultContextRoot}
+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 ServiceStatus that represent services which no longer exist in the configuration
+	var keys []string
+	for _, service := range config.Services {
+		keys = append(keys, service.Key())
+	}
+	numberOfServiceStatusesDeleted := storage.Get().DeleteAllServiceStatusesNotInKeys(keys)
+	if numberOfServiceStatusesDeleted > 0 {
+		log.Printf("[config][validateStorageConfig] Deleted %d service statuses because their matching services no longer existed", numberOfServiceStatusesDeleted)
+	}
+	return nil
+}
+
+func validateUIConfig(config *Config) error {
+	if config.UI == nil {
+		config.UI = GetDefaultUIConfig()
 	} else {
-		config.Web.validateAndSetDefaults()
+		if err := config.UI.validateAndSetDefaults(); err != nil {
+			return err
+		}
 	}
+	return nil
 }
 
-func validateKubernetesConfig(config *Config) {
-	if config.Kubernetes != nil && config.Kubernetes.AutoDiscover {
-		if config.Kubernetes.ServiceTemplate == nil {
-			panic("kubernetes.service-template cannot be nil")
-		}
-		if config.Debug {
-			log.Println("[config][validateKubernetesConfig] Automatically discovering Kubernetes services...")
-		}
-		discoveredServices, err := k8s.DiscoverServices(config.Kubernetes)
-		if err != nil {
-			panic(err)
-		}
-		config.Services = append(config.Services, discoveredServices...)
-		log.Printf("[config][validateKubernetesConfig] Discovered %d Kubernetes services", len(discoveredServices))
+func validateWebConfig(config *Config) error {
+	if config.Web == nil {
+		config.Web = GetDefaultWebConfig()
+	} else {
+		return config.Web.validateAndSetDefaults()
 	}
+	return nil
 }
 
-func validateServicesConfig(config *Config) {
+func validateServicesConfig(config *Config) error {
 	for _, service := range config.Services {
 		if config.Debug {
 			log.Printf("[config][validateServicesConfig] Validating service '%s'", service.Name)
 		}
-		service.ValidateAndSetDefaults()
+		if err := service.ValidateAndSetDefaults(); err != nil {
+			return err
+		}
 	}
 	log.Printf("[config][validateServicesConfig] Validated %d services", len(config.Services))
+	return nil
 }
 
-func validateSecurityConfig(config *Config) {
+func validateSecurityConfig(config *Config) error {
 	if config.Security != nil {
 		if config.Security.IsValid() {
 			if config.Debug {
@@ -195,29 +243,50 @@ func validateSecurityConfig(config *Config) {
 		} else {
 			// If there was an attempt to configure security, then it must mean that some confidential or private
 			// data are exposed. As a result, we'll force a panic because it's better to be safe than sorry.
-			panic(ErrInvalidSecurityConfig)
+			return ErrInvalidSecurityConfig
 		}
 	}
+	return nil
 }
 
-func validateAlertingConfig(config *Config) {
-	if config.Alerting == nil {
+// validateAlertingConfig validates the alerting configuration
+// Note that the alerting configuration has to be validated before the service configuration, because the default alert
+// returned by provider.AlertProvider.GetDefaultAlert() must be parsed before core.Service.ValidateAndSetDefaults()
+// sets the default alert values when none are set.
+func validateAlertingConfig(alertingConfig *alerting.Config, services []*core.Service, debug bool) {
+	if alertingConfig == nil {
 		log.Printf("[config][validateAlertingConfig] Alerting is not configured")
 		return
 	}
-	alertTypes := []core.AlertType{
-		core.SlackAlert,
-		core.MattermostAlert,
-		core.MessagebirdAlert,
-		core.TwilioAlert,
-		core.PagerDutyAlert,
-		core.CustomAlert,
+	alertTypes := []alert.Type{
+		alert.TypeCustom,
+		alert.TypeDiscord,
+		alert.TypeMattermost,
+		alert.TypeMessagebird,
+		alert.TypePagerDuty,
+		alert.TypeSlack,
+		alert.TypeTeams,
+		alert.TypeTelegram,
+		alert.TypeTwilio,
 	}
-	var validProviders, invalidProviders []core.AlertType
+	var validProviders, invalidProviders []alert.Type
 	for _, alertType := range alertTypes {
-		alertProvider := GetAlertingProviderByAlertType(config, alertType)
+		alertProvider := alertingConfig.GetAlertingProviderByAlertType(alertType)
 		if alertProvider != nil {
 			if alertProvider.IsValid() {
+				// Parse alerts with the provider's default alert
+				if alertProvider.GetDefaultAlert() != nil {
+					for _, service := range services {
+						for alertIndex, serviceAlert := range service.Alerts {
+							if alertType == serviceAlert.Type {
+								if debug {
+									log.Printf("[config][validateAlertingConfig] Parsing alert %d with provider's default alert for provider=%s in service=%s", alertIndex, alertType, service.Name)
+								}
+								provider.ParseWithDefaultAlert(alertProvider.GetDefaultAlert(), serviceAlert)
+							}
+						}
+					}
+				}
 				validProviders = append(validProviders, alertType)
 			} else {
 				log.Printf("[config][validateAlertingConfig] Ignoring provider=%s because configuration is invalid", alertType)
@@ -229,46 +298,3 @@ func validateAlertingConfig(config *Config) {
 	}
 	log.Printf("[config][validateAlertingConfig] configuredProviders=%s; ignoredProviders=%s", validProviders, invalidProviders)
 }
-
-// GetAlertingProviderByAlertType returns an provider.AlertProvider by its corresponding core.AlertType
-func GetAlertingProviderByAlertType(config *Config, alertType core.AlertType) provider.AlertProvider {
-	switch alertType {
-	case core.SlackAlert:
-		if config.Alerting.Slack == nil {
-			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
-			return nil
-		}
-		return config.Alerting.Slack
-	case core.MattermostAlert:
-		if config.Alerting.Mattermost == nil {
-			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
-			return nil
-		}
-		return config.Alerting.Mattermost
-	case core.MessagebirdAlert:
-		if config.Alerting.Messagebird == nil {
-			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
-			return nil
-		}
-		return config.Alerting.Messagebird
-	case core.TwilioAlert:
-		if config.Alerting.Twilio == nil {
-			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
-			return nil
-		}
-		return config.Alerting.Twilio
-	case core.PagerDutyAlert:
-		if config.Alerting.PagerDuty == nil {
-			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
-			return nil
-		}
-		return config.Alerting.PagerDuty
-	case core.CustomAlert:
-		if config.Alerting.Custom == nil {
-			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
-			return nil
-		}
-		return config.Alerting.Custom
-	}
-	return nil
-}

config/ui.go

@@ -0,0 +1,41 @@
+package config
+
+import (
+	"bytes"
+	"html/template"
+)
+
+const (
+	defaultTitle = "Health Dashboard | Gatus"
+	defaultLogo  = ""
+)
+
+// UIConfig is the configuration for the UI of Gatus
+type UIConfig struct {
+	Title string `yaml:"title"` // Title of the page
+	Logo  string `yaml:"logo"`  // Logo to display on the page
+}
+
+// GetDefaultUIConfig returns a UIConfig struct with the default values
+func GetDefaultUIConfig() *UIConfig {
+	return &UIConfig{
+		Title: defaultTitle,
+		Logo:  defaultLogo,
+	}
+}
+
+func (cfg *UIConfig) validateAndSetDefaults() error {
+	if len(cfg.Title) == 0 {
+		cfg.Title = defaultTitle
+	}
+	t, err := template.ParseFiles(StaticFolder + "/index.html")
+	if err != nil {
+		return err
+	}
+	var buffer bytes.Buffer
+	err = t.Execute(&buffer, cfg)
+	if err != nil {
+		return err
+	}
+	return nil
+}

config/ui_test.go

@@ -0,0 +1,24 @@
+package config
+
+import "testing"
+
+func TestUIConfig_validateAndSetDefaults(t *testing.T) {
+	StaticFolder = "../web/static"
+	defer func() {
+		StaticFolder = "./web/static"
+	}()
+	uiConfig := &UIConfig{Title: ""}
+	if err := uiConfig.validateAndSetDefaults(); err != nil {
+		t.Error("expected no error, got", err.Error())
+	}
+}
+
+func TestGetDefaultUIConfig(t *testing.T) {
+	defaultUIConfig := GetDefaultUIConfig()
+	if defaultUIConfig.Title != defaultTitle {
+		t.Error("expected GetDefaultUIConfig() to return defaultTitle, got", defaultUIConfig.Title)
+	}
+	if defaultUIConfig.Logo != defaultLogo {
+		t.Error("expected GetDefaultUIConfig() to return defaultLogo, got", defaultUIConfig.Logo)
+	}
+}

config/web.go

@@ -3,25 +3,25 @@ package config
 import (
 	"fmt"
 	"math"
-	"net/url"
-	"strings"
 )
 
-// webConfig is the structure which supports the configuration of the endpoint
+// WebConfig is the structure which supports the configuration of the endpoint
 // which provides access to the web frontend
-type webConfig struct {
+type WebConfig struct {
 	// Address to listen on (defaults to 0.0.0.0 specified by DefaultAddress)
 	Address string `yaml:"address"`
 
 	// Port to listen on (default to 8080 specified by DefaultPort)
 	Port int `yaml:"port"`
+}
 
-	// ContextRoot set the root context for the web application
-	ContextRoot string `yaml:"context-root"`
+// GetDefaultWebConfig returns a WebConfig struct with the default values
+func GetDefaultWebConfig() *WebConfig {
+	return &WebConfig{Address: DefaultAddress, Port: DefaultPort}
 }
 
 // validateAndSetDefaults checks and sets the default values for fields that are not set
-func (web *webConfig) validateAndSetDefaults() {
+func (web *WebConfig) validateAndSetDefaults() error {
 	// Validate the Address
 	if len(web.Address) == 0 {
 		web.Address = DefaultAddress
@@ -30,34 +30,12 @@ func (web *webConfig) validateAndSetDefaults() {
 	if web.Port == 0 {
 		web.Port = DefaultPort
 	} else if web.Port < 0 || web.Port > math.MaxUint16 {
-		panic(fmt.Sprintf("invalid port: value should be between %d and %d", 0, math.MaxUint16))
-	}
-	// Validate the ContextRoot
-	if len(web.ContextRoot) == 0 {
-		web.ContextRoot = DefaultContextRoot
-	} else {
-		trimmedContextRoot := strings.Trim(web.ContextRoot, "/")
-		if len(trimmedContextRoot) == 0 {
-			web.ContextRoot = DefaultContextRoot
-			return
-		}
-		rootContextURL, err := url.Parse(trimmedContextRoot)
-		if err != nil {
-			panic("invalid context root:" + err.Error())
-		}
-		if rootContextURL.Path != trimmedContextRoot {
-			panic("invalid context root: too complex")
-		}
-		web.ContextRoot = "/" + strings.Trim(rootContextURL.Path, "/") + "/"
+		return fmt.Errorf("invalid port: value should be between %d and %d", 0, math.MaxUint16)
 	}
+	return nil
 }
 
 // SocketAddress returns the combination of the Address and the Port
-func (web *webConfig) SocketAddress() string {
+func (web *WebConfig) SocketAddress() string {
 	return fmt.Sprintf("%s:%d", web.Address, web.Port)
 }
-
-// PrependWithContextRoot appends the given path to the ContextRoot
-func (web *webConfig) PrependWithContextRoot(path string) string {
-	return web.ContextRoot + strings.Trim(path, "/")
-}

config/web_test.go

@@ -1,12 +1,11 @@
 package config
 
 import (
-	"fmt"
 	"testing"
 )
 
 func TestWebConfig_SocketAddress(t *testing.T) {
-	web := &webConfig{
+	web := &WebConfig{
 		Address: "0.0.0.0",
 		Port:    8081,
 	}
@@ -14,86 +13,3 @@ func TestWebConfig_SocketAddress(t *testing.T) {
 		t.Errorf("expected %s, got %s", "0.0.0.0:8081", web.SocketAddress())
 	}
 }
-
-func TestWebConfig_PrependWithContextRoot(t *testing.T) {
-	web := &webConfig{ContextRoot: "/status/"}
-	if result := web.PrependWithContextRoot("/api/v1/results"); result != "/status/api/v1/results" {
-		t.Errorf("expected %s, got %s", "/status/api/v1/results", result)
-	}
-	if result := web.PrependWithContextRoot("/health"); result != "/status/health" {
-		t.Errorf("expected %s, got %s", "/status/health", result)
-	}
-	if result := web.PrependWithContextRoot("/health/"); result != "/status/health" {
-		t.Errorf("expected %s, got %s", "/status/health", result)
-	}
-}
-
-// validContextRootTest specifies all test case which should end up in
-// a valid context root used to bind the web interface to
-var validContextRootTests = []struct {
-	name         string
-	path         string
-	expectedPath string
-}{
-	{"Empty", "", "/"},
-	{"/", "/", "/"},
-	{"///", "///", "/"},
-	{"Single character 'a'", "a", "/a/"},
-	{"Slash at the beginning", "/status", "/status/"},
-	{"Slashes at start and end", "/status/", "/status/"},
-	{"Multiple slashes at start", "//status", "/status/"},
-	{"Multiple slashes at start and end", "///status////", "/status/"},
-	{"Contains '@' in path'", "me@/status/gatus", "/me@/status/gatus/"},
-	{"Nested context with trailing slash", "/status/gatus/", "/status/gatus/"},
-	{"Nested context without trailing slash", "/status/gatus/system", "/status/gatus/system/"},
-}
-
-func TestWebConfig_ValidContextRoots(t *testing.T) {
-	for idx, test := range validContextRootTests {
-		t.Run(fmt.Sprintf("%d: %s", idx, test.name), func(t *testing.T) {
-			expectValidResultForContextRoot(t, test.path, test.expectedPath)
-		})
-	}
-}
-
-func expectValidResultForContextRoot(t *testing.T, path string, expected string) {
-	web := &webConfig{
-		ContextRoot: path,
-	}
-	web.validateAndSetDefaults()
-	if web.ContextRoot != expected {
-		t.Errorf("expected %s, got %s", expected, web.ContextRoot)
-	}
-}
-
-// invalidContextRootTests contains all tests for context root which are
-// expected to fail and stop program execution
-var invalidContextRootTests = []struct {
-	name string
-	path string
-}{
-	{"Only a fragment identifier", "#"},
-	{"Invalid character in path", "/invalid" + string([]byte{0x7F})},
-	{"Starts with protocol", "http://status/gatus"},
-	{"Path with fragment", "/status/gatus#here"},
-	{"Starts with '://'", "://status"},
-	{"Contains query parameter", "/status/h?ello=world"},
-	{"Contains '?'", "/status?"},
-}
-
-func TestWebConfig_InvalidContextRoots(t *testing.T) {
-	for idx, test := range invalidContextRootTests {
-		t.Run(fmt.Sprintf("%d: %s", idx, test.name), func(t *testing.T) {
-			expectInvalidResultForContextRoot(t, test.path)
-		})
-	}
-}
-
-func expectInvalidResultForContextRoot(t *testing.T, path string) {
-	defer func() { recover() }()
-
-	web := &webConfig{ContextRoot: path}
-	web.validateAndSetDefaults()
-
-	t.Fatal(fmt.Sprintf("Should've panicked because the configuration specifies an invalid context root: %s", path))
-}

controller/badge.go

@@ -1,108 +0,0 @@
-package controller
-
-import (
-	"fmt"
-	"net/http"
-	"strings"
-	"time"
-
-	"github.com/TwinProduction/gatus/core"
-	"github.com/TwinProduction/gatus/watchdog"
-	"github.com/gorilla/mux"
-)
-
-// badgeHandler handles the automatic generation of badge based on the group name and service name passed.
-//
-// Valid values for {duration}: 7d, 24h, 1h
-// Pattern for {identifier}: group-<GROUP_NAME>-service-<SERVICE_NAME>.svg
-func badgeHandler(writer http.ResponseWriter, request *http.Request) {
-	variables := mux.Vars(request)
-	duration := variables["duration"]
-	// group-<GROUP_NAME>-service-<SERVICE_NAME>.svg
-	identifier := variables["identifier"]
-	if duration != "7d" && duration != "24h" && duration != "1h" {
-		writer.WriteHeader(http.StatusBadRequest)
-		_, _ = writer.Write([]byte("Durations supported: 7d, 24h, 1h"))
-		return
-	}
-	parts := strings.Split(identifier, "-service-")
-	if len(parts) != 2 || !strings.HasPrefix(identifier, "group-") || !strings.HasSuffix(identifier, ".svg") {
-		writer.WriteHeader(http.StatusBadRequest)
-		_, _ = writer.Write([]byte("Invalid path: Pattern should look like /group-<GROUP_NAME>-service-<SERVICE_NAME>.svg"))
-		return
-	}
-	groupName := strings.TrimPrefix(parts[0], "group-")
-	serviceName := strings.TrimSuffix(parts[1], ".svg")
-	uptime := watchdog.GetUptimeByServiceGroupAndName(groupName, serviceName)
-	if uptime == nil {
-		writer.WriteHeader(http.StatusNotFound)
-		_, _ = writer.Write([]byte("Requested service not found"))
-		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.Write(generateSVG(duration, uptime))
-}
-
-func generateSVG(duration string, uptime *core.Uptime) []byte {
-	var labelWidth, valueWidth, valueWidthAdjustment int
-	var color string
-	var value float64
-	switch duration {
-	case "7d":
-		labelWidth = 65
-		value = uptime.LastSevenDays
-	case "24h":
-		labelWidth = 70
-		value = uptime.LastTwentyFourHours
-	case "1h":
-		labelWidth = 65
-		value = uptime.LastHour
-	default:
-	}
-	if value >= 0.8 {
-		color = "#40cc11"
-	} else {
-		color = "#c7130a"
-	}
-	sanitizedValue := strings.TrimRight(strings.TrimRight(fmt.Sprintf("%.2f", value*100), "0"), ".") + "%"
-	if strings.Contains(sanitizedValue, ".") {
-		valueWidthAdjustment = -10
-	}
-	valueWidth = (len(sanitizedValue) * 11) + valueWidthAdjustment
-	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">
-      uptime %s
-    </text>
-    <text x="%d" y="14">
-      uptime %s
-    </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, duration, labelX, duration, valueX, sanitizedValue, valueX, sanitizedValue))
-	return svg
-}

controller/controller.go

@@ -1,114 +1,48 @@
 package controller
 
 import (
-	"bytes"
-	"compress/gzip"
+	"context"
 	"fmt"
 	"log"
 	"net/http"
-	"strings"
+	"os"
 	"time"
 
 	"github.com/TwinProduction/gatus/config"
+	"github.com/TwinProduction/gatus/controller/handler"
 	"github.com/TwinProduction/gatus/security"
-	"github.com/TwinProduction/gatus/watchdog"
-	"github.com/TwinProduction/gocache"
-	"github.com/gorilla/mux"
-	"github.com/prometheus/client_golang/prometheus/promhttp"
-)
-
-const (
-	cacheTTL = 10 * time.Second
 )
 
 var (
-	cache = gocache.NewCache().WithMaxSize(100).WithEvictionPolicy(gocache.LeastRecentlyUsed)
+	// server is the http.Server created by Handle.
+	// The only reason it exists is for testing purposes.
+	server *http.Server
 )
 
-func init() {
-	if err := cache.StartJanitor(); err != nil {
-		log.Fatal("[controller][init] Failed to start cache janitor:", err.Error())
-	}
-}
-
 // Handle creates the router and starts the server
-func Handle() {
-	cfg := config.Get()
-	router := CreateRouter(cfg)
-	server := &http.Server{
-		Addr:         fmt.Sprintf("%s:%d", cfg.Web.Address, cfg.Web.Port),
+func Handle(securityConfig *security.Config, webConfig *config.WebConfig, uiConfig *config.UIConfig, enableMetrics bool) {
+	var router http.Handler = handler.CreateRouter(config.StaticFolder, securityConfig, uiConfig, enableMetrics)
+	if os.Getenv("ENVIRONMENT") == "dev" {
+		router = handler.DevelopmentCORS(router)
+	}
+	server = &http.Server{
+		Addr:         fmt.Sprintf("%s:%d", webConfig.Address, webConfig.Port),
 		Handler:      router,
 		ReadTimeout:  15 * time.Second,
 		WriteTimeout: 15 * time.Second,
 		IdleTimeout:  15 * time.Second,
 	}
-	log.Printf("[controller][Handle] Listening on %s%s\n", cfg.Web.SocketAddress(), cfg.Web.ContextRoot)
-	log.Fatal(server.ListenAndServe())
+	log.Println("[controller][Handle] Listening on " + webConfig.SocketAddress())
+	if os.Getenv("ROUTER_TEST") == "true" {
+		return
+	}
+	log.Println("[controller][Handle]", server.ListenAndServe())
 }
 
-// CreateRouter creates the router for the http server
-func CreateRouter(cfg *config.Config) *mux.Router {
-	router := mux.NewRouter()
-	statusesHandler := serviceStatusesHandler
-	if cfg.Security != nil && cfg.Security.IsValid() {
-		statusesHandler = security.Handler(serviceStatusesHandler, cfg.Security)
+// Shutdown stops the server
+func Shutdown() {
+	if server != nil {
+		_ = server.Shutdown(context.TODO())
+		server = nil
 	}
-	router.HandleFunc("/favicon.ico", favIconHandler).Methods("GET") // favicon needs to be always served from the root
-	router.HandleFunc(cfg.Web.PrependWithContextRoot("/api/v1/statuses"), statusesHandler).Methods("GET")
-	router.HandleFunc(cfg.Web.PrependWithContextRoot("/api/v1/badges/uptime/{duration}/{identifier}"), badgeHandler).Methods("GET")
-	router.HandleFunc(cfg.Web.PrependWithContextRoot("/health"), healthHandler).Methods("GET")
-	router.PathPrefix(cfg.Web.ContextRoot).Handler(GzipHandler(http.StripPrefix(cfg.Web.ContextRoot, http.FileServer(http.Dir("./static")))))
-	if cfg.Metrics {
-		router.Handle(cfg.Web.PrependWithContextRoot("/metrics"), promhttp.Handler()).Methods("GET")
-	}
-	return router
-}
-
-func serviceStatusesHandler(writer http.ResponseWriter, r *http.Request) {
-	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("service-status-gzipped")
-	} else {
-		value, exists = cache.Get("service-status")
-	}
-	var data []byte
-	if !exists {
-		var err error
-		buffer := &bytes.Buffer{}
-		gzipWriter := gzip.NewWriter(buffer)
-		data, err = watchdog.GetServiceStatusesAsJSON()
-		if err != nil {
-			log.Printf("[main][serviceStatusesHandler] Unable to marshal object to JSON: %s", err.Error())
-			writer.WriteHeader(http.StatusInternalServerError)
-			_, _ = writer.Write([]byte("Unable to marshal object to JSON"))
-			return
-		}
-		_, _ = gzipWriter.Write(data)
-		_ = gzipWriter.Close()
-		gzippedData := buffer.Bytes()
-		cache.SetWithTTL("service-status", data, cacheTTL)
-		cache.SetWithTTL("service-status-gzipped", gzippedData, cacheTTL)
-		if gzipped {
-			data = gzippedData
-		}
-	} else {
-		data = value.([]byte)
-	}
-	writer.Header().Add("Content-Type", "application/json")
-	writer.WriteHeader(http.StatusOK)
-	_, _ = writer.Write(data)
-}
-
-func healthHandler(writer http.ResponseWriter, _ *http.Request) {
-	writer.Header().Add("Content-Type", "application/json")
-	writer.WriteHeader(http.StatusOK)
-	_, _ = writer.Write([]byte("{\"status\":\"UP\"}"))
-}
-
-// favIconHandler handles requests for /favicon.ico
-func favIconHandler(writer http.ResponseWriter, request *http.Request) {
-	http.ServeFile(writer, request, "./static/favicon.ico")
 }

controller/controller_test.go

@@ -0,0 +1,54 @@
+package controller
+
+import (
+	"math/rand"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+
+	"github.com/TwinProduction/gatus/config"
+	"github.com/TwinProduction/gatus/core"
+)
+
+func TestHandle(t *testing.T) {
+	cfg := &config.Config{
+		Web: &config.WebConfig{
+			Address: "0.0.0.0",
+			Port:    rand.Intn(65534),
+		},
+		Services: []*core.Service{
+			{
+				Name:  "frontend",
+				Group: "core",
+			},
+			{
+				Name:  "backend",
+				Group: "core",
+			},
+		},
+	}
+	_ = os.Setenv("ROUTER_TEST", "true")
+	_ = os.Setenv("ENVIRONMENT", "dev")
+	defer os.Clearenv()
+	Handle(cfg.Security, cfg.Web, cfg.UI, cfg.Metrics)
+	defer Shutdown()
+	request, _ := http.NewRequest("GET", "/health", nil)
+	responseRecorder := httptest.NewRecorder()
+	server.Handler.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusOK {
+		t.Error("expected GET /health to return status code 200")
+	}
+	if server == nil {
+		t.Fatal("server should've been set (but because we set ROUTER_TEST, it shouldn't have been started)")
+	}
+}
+
+func TestShutdown(t *testing.T) {
+	// Pretend that we called controller.Handle(), which initializes the server variable
+	server = &http.Server{}
+	Shutdown()
+	if server != nil {
+		t.Error("server should've been shut down")
+	}
+}

controller/gzip.go

@@ -1,51 +0,0 @@
-package controller
-
-import (
-	"compress/gzip"
-	"io"
-	"io/ioutil"
-	"net/http"
-	"strings"
-	"sync"
-)
-
-var gzPool = sync.Pool{
-	New: func() interface{} {
-		return gzip.NewWriter(ioutil.Discard)
-	},
-}
-
-type gzipResponseWriter struct {
-	io.Writer
-	http.ResponseWriter
-}
-
-// WriteHeader sends an HTTP response header with the provided status code.
-// It also deletes the Content-Length header, since the GZIP compression may modify the size of the payload
-func (w *gzipResponseWriter) WriteHeader(status int) {
-	w.Header().Del("Content-Length")
-	w.ResponseWriter.WriteHeader(status)
-}
-
-// Write writes len(b) bytes from b to the underlying data stream.
-func (w *gzipResponseWriter) Write(b []byte) (int, error) {
-	return w.Writer.Write(b)
-}
-
-// GzipHandler compresses the response of a given handler if the request's headers specify that the client
-// supports gzip encoding
-func GzipHandler(next http.Handler) http.Handler {
-	return http.HandlerFunc(func(writer http.ResponseWriter, r *http.Request) {
-		// If the request doesn't specify that it supports gzip, then don't compress it
-		if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
-			next.ServeHTTP(writer, r)
-			return
-		}
-		writer.Header().Set("Content-Encoding", "gzip")
-		gz := gzPool.Get().(*gzip.Writer)
-		defer gzPool.Put(gz)
-		gz.Reset(writer)
-		defer gz.Close()
-		next.ServeHTTP(&gzipResponseWriter{ResponseWriter: writer, Writer: gz}, r)
-	})
-}

controller/handler/badge.go

@@ -0,0 +1,229 @@
+package handler
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gatus/storage/store/common"
+	"github.com/gorilla/mux"
+)
+
+const (
+	badgeColorHexAwesome  = "#40cc11"
+	badgeColorHexGreat    = "#94cc11"
+	badgeColorHexGood     = "#ccd311"
+	badgeColorHexPassable = "#ccb311"
+	badgeColorHexBad      = "#cc8111"
+	badgeColorHexVeryBad  = "#c7130a"
+)
+
+// UptimeBadge handles the automatic generation of badge based on the group name and service name passed.
+//
+// Valid values for {duration}: 7d, 24h, 1h
+func UptimeBadge(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 uptime 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"]
+	uptime, err := storage.Get().GetUptimeByKey(key, from, time.Now())
+	if err != nil {
+		if err == common.ErrServiceNotFound {
+			writer.WriteHeader(http.StatusNotFound)
+		} else if err == common.ErrInvalidTimeRange {
+			writer.WriteHeader(http.StatusBadRequest)
+		} else {
+			writer.WriteHeader(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.Write(generateUptimeBadgeSVG(duration, uptime))
+}
+
+// ResponseTimeBadge handles the automatic generation of badge based on the group name and service 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
+	}
+	key := variables["key"]
+	averageResponseTime, err := storage.Get().GetAverageResponseTimeByKey(key, from, time.Now())
+	if err != nil {
+		if err == common.ErrServiceNotFound {
+			writer.WriteHeader(http.StatusNotFound)
+		} else if err == common.ErrInvalidTimeRange {
+			writer.WriteHeader(http.StatusBadRequest)
+		} else {
+			writer.WriteHeader(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.Write(generateResponseTimeBadgeSVG(duration, averageResponseTime))
+}
+
+func generateUptimeBadgeSVG(duration string, uptime float64) []byte {
+	var labelWidth, valueWidth, valueWidthAdjustment int
+	switch duration {
+	case "7d":
+		labelWidth = 65
+	case "24h":
+		labelWidth = 70
+	case "1h":
+		labelWidth = 65
+	default:
+	}
+	color := getBadgeColorFromUptime(uptime)
+	sanitizedValue := strings.TrimRight(strings.TrimRight(fmt.Sprintf("%.2f", uptime*100), "0"), ".") + "%"
+	if strings.Contains(sanitizedValue, ".") {
+		valueWidthAdjustment = -10
+	}
+	valueWidth = (len(sanitizedValue) * 11) + valueWidthAdjustment
+	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">
+      uptime %s
+    </text>
+    <text x="%d" y="14">
+      uptime %s
+    </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, duration, labelX, duration, valueX, sanitizedValue, valueX, sanitizedValue))
+	return svg
+}
+
+func getBadgeColorFromUptime(uptime float64) string {
+	if uptime >= 0.975 {
+		return badgeColorHexAwesome
+	} else if uptime >= 0.95 {
+		return badgeColorHexGreat
+	} else if uptime >= 0.9 {
+		return badgeColorHexGood
+	} else if uptime >= 0.8 {
+		return badgeColorHexPassable
+	} else if uptime >= 0.65 {
+		return badgeColorHexBad
+	}
+	return badgeColorHexVeryBad
+}
+
+func generateResponseTimeBadgeSVG(duration string, averageResponseTime int) []byte {
+	var labelWidth, valueWidth int
+	switch duration {
+	case "7d":
+		labelWidth = 105
+	case "24h":
+		labelWidth = 110
+	case "1h":
+		labelWidth = 105
+	default:
+	}
+	color := getBadgeColorFromResponseTime(averageResponseTime)
+	sanitizedValue := strconv.Itoa(averageResponseTime) + "ms"
+	valueWidth = len(sanitizedValue) * 11
+	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">
+      response time %s
+    </text>
+    <text x="%d" y="14">
+      response time %s
+    </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, duration, labelX, duration, valueX, sanitizedValue, valueX, sanitizedValue))
+	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
+	}
+	return badgeColorHexVeryBad
+}

controller/handler/badge_test.go

@@ -0,0 +1,221 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strconv"
+	"testing"
+	"time"
+
+	"github.com/TwinProduction/gatus/config"
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gatus/watchdog"
+)
+
+func TestUptimeBadge(t *testing.T) {
+	defer storage.Get().Clear()
+	defer cache.Clear()
+	cfg := &config.Config{
+		Metrics: true,
+		Services: []*core.Service{
+			{
+				Name:  "frontend",
+				Group: "core",
+			},
+			{
+				Name:  "backend",
+				Group: "core",
+			},
+		},
+	}
+	watchdog.UpdateServiceStatuses(cfg.Services[0], &core.Result{Success: true, Duration: time.Millisecond, Timestamp: time.Now()})
+	watchdog.UpdateServiceStatuses(cfg.Services[1], &core.Result{Success: false, Duration: time.Second, Timestamp: time.Now()})
+	router := CreateRouter("../../web/static", cfg.Security, nil, cfg.Metrics)
+	type Scenario struct {
+		Name         string
+		Path         string
+		ExpectedCode int
+		Gzip         bool
+	}
+	scenarios := []Scenario{
+		{
+			Name:         "badge-uptime-1h",
+			Path:         "/api/v1/services/core_frontend/uptimes/1h/badge.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badge-uptime-24h",
+			Path:         "/api/v1/services/core_backend/uptimes/24h/badge.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badge-uptime-7d",
+			Path:         "/api/v1/services/core_frontend/uptimes/7d/badge.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badge-uptime-with-invalid-duration",
+			Path:         "/api/v1/services/core_backend/uptimes/3d/badge.svg",
+			ExpectedCode: http.StatusBadRequest,
+		},
+		{
+			Name:         "badge-uptime-for-invalid-key",
+			Path:         "/api/v1/services/invalid_key/uptimes/7d/badge.svg",
+			ExpectedCode: http.StatusNotFound,
+		},
+		{
+			Name:         "badge-response-time-1h",
+			Path:         "/api/v1/services/core_frontend/response-times/1h/badge.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badge-response-time-24h",
+			Path:         "/api/v1/services/core_backend/response-times/24h/badge.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badge-response-time-7d",
+			Path:         "/api/v1/services/core_frontend/response-times/7d/badge.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badge-response-time-with-invalid-duration",
+			Path:         "/api/v1/services/core_backend/response-times/3d/badge.svg",
+			ExpectedCode: http.StatusBadRequest,
+		},
+		{
+			Name:         "badge-response-time-for-invalid-key",
+			Path:         "/api/v1/services/invalid_key/response-times/7d/badge.svg",
+			ExpectedCode: http.StatusNotFound,
+		},
+		{
+			Name:         "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)
+			if scenario.Gzip {
+				request.Header.Set("Accept-Encoding", "gzip")
+			}
+			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)
+			}
+		})
+	}
+}
+
+func TestGetBadgeColorFromUptime(t *testing.T) {
+	scenarios := []struct {
+		Uptime        float64
+		ExpectedColor string
+	}{
+		{
+			Uptime:        1,
+			ExpectedColor: badgeColorHexAwesome,
+		},
+		{
+			Uptime:        0.99,
+			ExpectedColor: badgeColorHexAwesome,
+		},
+		{
+			Uptime:        0.97,
+			ExpectedColor: badgeColorHexGreat,
+		},
+		{
+			Uptime:        0.95,
+			ExpectedColor: badgeColorHexGreat,
+		},
+		{
+			Uptime:        0.93,
+			ExpectedColor: badgeColorHexGood,
+		},
+		{
+			Uptime:        0.9,
+			ExpectedColor: badgeColorHexGood,
+		},
+		{
+			Uptime:        0.85,
+			ExpectedColor: badgeColorHexPassable,
+		},
+		{
+			Uptime:        0.7,
+			ExpectedColor: badgeColorHexBad,
+		},
+		{
+			Uptime:        0.65,
+			ExpectedColor: badgeColorHexBad,
+		},
+		{
+			Uptime:        0.6,
+			ExpectedColor: badgeColorHexVeryBad,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run("uptime-"+strconv.Itoa(int(scenario.Uptime*100)), func(t *testing.T) {
+			if getBadgeColorFromUptime(scenario.Uptime) != scenario.ExpectedColor {
+				t.Errorf("expected %s from %f, got %v", scenario.ExpectedColor, scenario.Uptime, getBadgeColorFromUptime(scenario.Uptime))
+			}
+		})
+	}
+}
+
+func TestGetBadgeColorFromResponseTime(t *testing.T) {
+	scenarios := []struct {
+		ResponseTime  int
+		ExpectedColor string
+	}{
+		{
+			ResponseTime:  10,
+			ExpectedColor: badgeColorHexAwesome,
+		},
+		{
+			ResponseTime:  50,
+			ExpectedColor: badgeColorHexAwesome,
+		},
+		{
+			ResponseTime:  75,
+			ExpectedColor: badgeColorHexGreat,
+		},
+		{
+			ResponseTime:  150,
+			ExpectedColor: badgeColorHexGreat,
+		},
+		{
+			ResponseTime:  201,
+			ExpectedColor: badgeColorHexGood,
+		},
+		{
+			ResponseTime:  300,
+			ExpectedColor: badgeColorHexGood,
+		},
+		{
+			ResponseTime:  301,
+			ExpectedColor: badgeColorHexPassable,
+		},
+		{
+			ResponseTime:  450,
+			ExpectedColor: badgeColorHexPassable,
+		},
+		{
+			ResponseTime:  700,
+			ExpectedColor: badgeColorHexBad,
+		},
+		{
+			ResponseTime:  1500,
+			ExpectedColor: badgeColorHexVeryBad,
+		},
+	}
+	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))
+			}
+		})
+	}
+}

controller/handler/chart.go

@@ -0,0 +1,121 @@
+package handler
+
+import (
+	"log"
+	"math"
+	"net/http"
+	"sort"
+	"time"
+
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gatus/storage/store/common"
+	"github.com/gorilla/mux"
+	"github.com/wcharczuk/go-chart/v2"
+	"github.com/wcharczuk/go-chart/v2/drawing"
+)
+
+const timeFormat = "3:04PM"
+
+var (
+	gridStyle = chart.Style{
+		StrokeColor: drawing.Color{R: 119, G: 119, B: 119, A: 40},
+		StrokeWidth: 1.0,
+	}
+	axisStyle = chart.Style{
+		FontColor: drawing.Color{R: 119, G: 119, B: 119, A: 255},
+	}
+	transparentStyle = chart.Style{
+		FillColor: drawing.Color{R: 255, G: 255, B: 255, A: 0},
+	}
+)
+
+func ResponseTimeChart(writer http.ResponseWriter, r *http.Request) {
+	vars := mux.Vars(r)
+	duration := vars["duration"]
+	var from time.Time
+	switch duration {
+	case "7d":
+		from = time.Now().Truncate(time.Hour).Add(-24 * 7 * time.Hour)
+	case "24h":
+		from = time.Now().Truncate(time.Hour).Add(-24 * time.Hour)
+	default:
+		http.Error(writer, "Durations supported: 7d, 24h", http.StatusBadRequest)
+		return
+	}
+	hourlyAverageResponseTime, err := storage.Get().GetHourlyAverageResponseTimeByKey(vars["key"], from, time.Now())
+	if err != nil {
+		if err == common.ErrServiceNotFound {
+			writer.WriteHeader(http.StatusNotFound)
+		} else if err == common.ErrInvalidTimeRange {
+			writer.WriteHeader(http.StatusBadRequest)
+		} else {
+			writer.WriteHeader(http.StatusInternalServerError)
+		}
+		_, _ = writer.Write([]byte(err.Error()))
+		return
+	}
+	if len(hourlyAverageResponseTime) == 0 {
+		writer.WriteHeader(http.StatusNoContent)
+		_, _ = writer.Write(nil)
+		return
+	}
+	series := chart.TimeSeries{
+		Name: "Average response time per hour",
+		Style: chart.Style{
+			StrokeWidth: 1.5,
+			DotWidth:    2.0,
+		},
+	}
+	keys := make([]int, 0, len(hourlyAverageResponseTime))
+	earliestTimestamp := int64(0)
+	for hourlyTimestamp := range hourlyAverageResponseTime {
+		keys = append(keys, int(hourlyTimestamp))
+		if earliestTimestamp == 0 || hourlyTimestamp < earliestTimestamp {
+			earliestTimestamp = hourlyTimestamp
+		}
+	}
+	for earliestTimestamp > from.Unix() {
+		earliestTimestamp -= int64(time.Hour.Seconds())
+		keys = append(keys, int(earliestTimestamp))
+	}
+	sort.Ints(keys)
+	var maxAverageResponseTime float64
+	for _, key := range keys {
+		averageResponseTime := float64(hourlyAverageResponseTime[int64(key)])
+		if maxAverageResponseTime < averageResponseTime {
+			maxAverageResponseTime = averageResponseTime
+		}
+		series.XValues = append(series.XValues, time.Unix(int64(key), 0))
+		series.YValues = append(series.YValues, averageResponseTime)
+	}
+	graph := chart.Chart{
+		Canvas:     transparentStyle,
+		Background: transparentStyle,
+		Width:      1280,
+		Height:     300,
+		XAxis: chart.XAxis{
+			ValueFormatter: chart.TimeValueFormatterWithFormat(timeFormat),
+			GridMajorStyle: gridStyle,
+			GridMinorStyle: gridStyle,
+			Style:          axisStyle,
+			NameStyle:      axisStyle,
+		},
+		YAxis: chart.YAxis{
+			Name:           "Average response time",
+			GridMajorStyle: gridStyle,
+			GridMinorStyle: gridStyle,
+			Style:          axisStyle,
+			NameStyle:      axisStyle,
+			Range: &chart.ContinuousRange{
+				Min: 0,
+				Max: math.Ceil(maxAverageResponseTime * 1.25),
+			},
+		},
+		Series: []chart.Series{series},
+	}
+	writer.Header().Set("Content-Type", "image/svg+xml")
+	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

@@ -0,0 +1,75 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/TwinProduction/gatus/config"
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gatus/watchdog"
+)
+
+func TestResponseTimeChart(t *testing.T) {
+	defer storage.Get().Clear()
+	defer cache.Clear()
+	cfg := &config.Config{
+		Metrics: true,
+		Services: []*core.Service{
+			{
+				Name:  "frontend",
+				Group: "core",
+			},
+			{
+				Name:  "backend",
+				Group: "core",
+			},
+		},
+	}
+	watchdog.UpdateServiceStatuses(cfg.Services[0], &core.Result{Success: true, Duration: time.Millisecond, Timestamp: time.Now()})
+	watchdog.UpdateServiceStatuses(cfg.Services[1], &core.Result{Success: false, Duration: time.Second, Timestamp: time.Now()})
+	router := CreateRouter("../../web/static", cfg.Security, nil, cfg.Metrics)
+	type Scenario struct {
+		Name         string
+		Path         string
+		ExpectedCode int
+		Gzip         bool
+	}
+	scenarios := []Scenario{
+		{
+			Name:         "chart-response-time-24h",
+			Path:         "/api/v1/services/core_backend/response-times/24h/chart.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "chart-response-time-7d",
+			Path:         "/api/v1/services/core_frontend/response-times/7d/chart.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "chart-response-time-with-invalid-duration",
+			Path:         "/api/v1/services/core_backend/response-times/3d/chart.svg",
+			ExpectedCode: http.StatusBadRequest,
+		},
+		{
+			Name:         "chart-response-time-for-invalid-key",
+			Path:         "/api/v1/services/invalid_key/response-times/7d/chart.svg",
+			ExpectedCode: http.StatusNotFound,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			if scenario.Gzip {
+				request.Header.Set("Accept-Encoding", "gzip")
+			}
+			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)
+			}
+		})
+	}
+}

controller/handler/cors.go

@@ -0,0 +1,10 @@
+package handler
+
+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-Origin", "http://localhost:8081")
+		next.ServeHTTP(w, r)
+	})
+}

controller/handler/favicon.go

@@ -0,0 +1,12 @@
+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

@@ -0,0 +1,33 @@
+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)
+			}
+		})
+	}
+}

controller/handler/gzip.go

@@ -0,0 +1,59 @@
+package handler
+
+import (
+	"compress/gzip"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"strings"
+	"sync"
+)
+
+var gzPool = sync.Pool{
+	New: func() interface{} {
+		return gzip.NewWriter(ioutil.Discard)
+	},
+}
+
+type gzipResponseWriter struct {
+	io.Writer
+	http.ResponseWriter
+}
+
+// WriteHeader sends an HTTP response header with the provided status code.
+// It also deletes the Content-Length header, since the GZIP compression may modify the size of the payload
+func (w *gzipResponseWriter) WriteHeader(status int) {
+	w.Header().Del("Content-Length")
+	w.ResponseWriter.WriteHeader(status)
+}
+
+// Write writes len(b) bytes from b to the underlying data stream.
+func (w *gzipResponseWriter) Write(b []byte) (int, error) {
+	return w.Writer.Write(b)
+}
+
+// GzipHandler compresses the response of a given http.Handler if the request's headers specify that the client
+// supports gzip encoding
+func GzipHandler(next http.Handler) http.Handler {
+	return GzipHandlerFunc(func(writer http.ResponseWriter, r *http.Request) {
+		next.ServeHTTP(writer, r)
+	})
+}
+
+// GzipHandlerFunc compresses the response of a given http.HandlerFunc if the request's headers specify that the client
+// supports gzip encoding
+func GzipHandlerFunc(next http.HandlerFunc) http.HandlerFunc {
+	return func(writer http.ResponseWriter, r *http.Request) {
+		// If the request doesn't specify that it supports gzip, then don't compress it
+		if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
+			next.ServeHTTP(writer, r)
+			return
+		}
+		writer.Header().Set("Content-Encoding", "gzip")
+		gz := gzPool.Get().(*gzip.Writer)
+		defer gzPool.Put(gz)
+		gz.Reset(writer)
+		defer gz.Close()
+		next.ServeHTTP(&gzipResponseWriter{ResponseWriter: writer, Writer: gz}, r)
+	}
+}

controller/handler/handler.go

@@ -0,0 +1,41 @@
+package handler
+
+import (
+	"net/http"
+
+	"github.com/TwinProduction/gatus/config"
+	"github.com/TwinProduction/gatus/security"
+	"github.com/TwinProduction/health"
+	"github.com/gorilla/mux"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+func CreateRouter(staticFolder string, securityConfig *security.Config, uiConfig *config.UIConfig, enabledMetrics bool) *mux.Router {
+	router := mux.NewRouter()
+	if enabledMetrics {
+		router.Handle("/metrics", promhttp.Handler()).Methods("GET")
+	}
+	router.Handle("/health", health.Handler().WithJSON(true)).Methods("GET")
+	router.HandleFunc("/favicon.ico", FavIcon(staticFolder)).Methods("GET")
+	// Endpoints
+	router.HandleFunc("/api/v1/services/statuses", secureIfNecessary(securityConfig, ServiceStatuses)).Methods("GET") // No GzipHandler for this one, because we cache the content as Gzipped already
+	router.HandleFunc("/api/v1/services/{key}/statuses", secureIfNecessary(securityConfig, GzipHandlerFunc(ServiceStatus))).Methods("GET")
+	// TODO: router.HandleFunc("/api/v1/services/{key}/uptimes", secureIfNecessary(securityConfig, GzipHandlerFunc(serviceUptimesHandler))).Methods("GET")
+	// TODO: router.HandleFunc("/api/v1/services/{key}/events", secureIfNecessary(securityConfig, GzipHandlerFunc(serviceEventsHandler))).Methods("GET")
+	router.HandleFunc("/api/v1/services/{key}/uptimes/{duration}/badge.svg", UptimeBadge).Methods("GET")
+	router.HandleFunc("/api/v1/services/{key}/response-times/{duration}/badge.svg", ResponseTimeBadge).Methods("GET")
+	router.HandleFunc("/api/v1/services/{key}/response-times/{duration}/chart.svg", ResponseTimeChart).Methods("GET")
+	// SPA
+	router.HandleFunc("/services/{service}", SinglePageApplication(staticFolder, uiConfig)).Methods("GET")
+	router.HandleFunc("/", SinglePageApplication(staticFolder, uiConfig)).Methods("GET")
+	// Everything else falls back on static content
+	router.PathPrefix("/").Handler(GzipHandler(http.FileServer(http.Dir(staticFolder))))
+	return router
+}
+
+func secureIfNecessary(securityConfig *security.Config, handler http.HandlerFunc) http.HandlerFunc {
+	if securityConfig != nil && securityConfig.IsValid() {
+		return security.Handler(handler, securityConfig)
+	}
+	return handler
+}

controller/handler/handler_test.go

@@ -0,0 +1,58 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestCreateRouter(t *testing.T) {
+	router := CreateRouter("../../web/static", nil, nil, true)
+	type Scenario struct {
+		Name         string
+		Path         string
+		ExpectedCode int
+		Gzip         bool
+	}
+	scenarios := []Scenario{
+		{
+			Name:         "health",
+			Path:         "/health",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "metrics",
+			Path:         "/metrics",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "scripts",
+			Path:         "/js/app.js",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "scripts-gzipped",
+			Path:         "/js/app.js",
+			ExpectedCode: http.StatusOK,
+			Gzip:         true,
+		},
+		{
+			Name:         "index-redirect",
+			Path:         "/index.html",
+			ExpectedCode: http.StatusMovedPermanently,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			if scenario.Gzip {
+				request.Header.Set("Accept-Encoding", "gzip")
+			}
+			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)
+			}
+		})
+	}
+}

controller/handler/service_status.go

@@ -0,0 +1,103 @@
+package handler
+
+import (
+	"bytes"
+	"compress/gzip"
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gatus/storage/store/common"
+	"github.com/TwinProduction/gatus/storage/store/common/paging"
+	"github.com/TwinProduction/gocache"
+	"github.com/gorilla/mux"
+)
+
+const (
+	cacheTTL = 10 * time.Second
+)
+
+var (
+	cache = gocache.NewCache().WithMaxSize(100).WithEvictionPolicy(gocache.FirstInFirstOut)
+)
+
+// ServiceStatuses handles requests to retrieve all service statuses
+// Due to the size of the response, this function leverages a cache.
+// Must not be wrapped by GzipHandler
+func ServiceStatuses(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("service-status-%d-%d-gzipped", page, pageSize))
+	} else {
+		value, exists = cache.Get(fmt.Sprintf("service-status-%d-%d", page, pageSize))
+	}
+	var data []byte
+	if !exists {
+		var err error
+		buffer := &bytes.Buffer{}
+		gzipWriter := gzip.NewWriter(buffer)
+		serviceStatuses, err := storage.Get().GetAllServiceStatuses(paging.NewServiceStatusParams().WithResults(page, pageSize))
+		if err != nil {
+			log.Printf("[handler][ServiceStatuses] Failed to retrieve service statuses: %s", err.Error())
+			http.Error(writer, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		data, err = json.Marshal(serviceStatuses)
+		if err != nil {
+			log.Printf("[handler][ServiceStatuses] 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("service-status-%d-%d", page, pageSize), data, cacheTTL)
+		cache.SetWithTTL(fmt.Sprintf("service-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)
+}
+
+// ServiceStatus retrieves a single ServiceStatus by group name and service name
+func ServiceStatus(writer http.ResponseWriter, r *http.Request) {
+	page, pageSize := extractPageAndPageSizeFromRequest(r)
+	vars := mux.Vars(r)
+	serviceStatus, err := storage.Get().GetServiceStatusByKey(vars["key"], paging.NewServiceStatusParams().WithResults(page, pageSize).WithEvents(1, common.MaximumNumberOfEvents))
+	if err != nil {
+		if err == common.ErrServiceNotFound {
+			http.Error(writer, err.Error(), http.StatusNotFound)
+			return
+		}
+		log.Printf("[handler][ServiceStatus] Failed to retrieve service status: %s", err.Error())
+		http.Error(writer, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	if serviceStatus == nil {
+		log.Printf("[handler][ServiceStatus] Service with key=%s not found", vars["key"])
+		http.Error(writer, "not found", http.StatusNotFound)
+		return
+	}
+	output, err := json.Marshal(serviceStatus)
+	if err != nil {
+		log.Printf("[handler][ServiceStatus] Unable to marshal object to JSON: %s", err.Error())
+		http.Error(writer, "unable to marshal object to JSON", http.StatusInternalServerError)
+		return
+	}
+	writer.Header().Add("Content-Type", "application/json")
+	writer.WriteHeader(http.StatusOK)
+	_, _ = writer.Write(output)
+}

controller/handler/service_status_test.go

@@ -0,0 +1,215 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/TwinProduction/gatus/config"
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gatus/watchdog"
+)
+
+var (
+	firstCondition  = core.Condition("[STATUS] == 200")
+	secondCondition = core.Condition("[RESPONSE_TIME] < 500")
+	thirdCondition  = core.Condition("[CERTIFICATE_EXPIRATION] < 72h")
+
+	timestamp = time.Now()
+
+	testService = core.Service{
+		Name:                    "name",
+		Group:                   "group",
+		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,
+	}
+	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,
+			},
+		},
+	}
+	testUnsuccessfulResult = core.Result{
+		Hostname:              "example.org",
+		IP:                    "127.0.0.1",
+		HTTPStatus:            200,
+		Errors:                []string{"error-1", "error-2"},
+		Connected:             true,
+		Success:               false,
+		Timestamp:             timestamp,
+		Duration:              750 * time.Millisecond,
+		CertificateExpiration: 10 * time.Hour,
+		ConditionResults: []*core.ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   false,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   false,
+			},
+		},
+	}
+)
+
+func TestServiceStatus(t *testing.T) {
+	defer storage.Get().Clear()
+	defer cache.Clear()
+	cfg := &config.Config{
+		Metrics: true,
+		Services: []*core.Service{
+			{
+				Name:  "frontend",
+				Group: "core",
+			},
+			{
+				Name:  "backend",
+				Group: "core",
+			},
+		},
+	}
+	watchdog.UpdateServiceStatuses(cfg.Services[0], &core.Result{Success: true, Duration: time.Millisecond, Timestamp: time.Now()})
+	watchdog.UpdateServiceStatuses(cfg.Services[1], &core.Result{Success: false, Duration: time.Second, Timestamp: time.Now()})
+	router := CreateRouter("../../web/static", cfg.Security, nil, cfg.Metrics)
+
+	type Scenario struct {
+		Name         string
+		Path         string
+		ExpectedCode int
+		Gzip         bool
+	}
+	scenarios := []Scenario{
+		{
+			Name:         "service-status",
+			Path:         "/api/v1/services/core_frontend/statuses",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "service-status-gzip",
+			Path:         "/api/v1/services/core_frontend/statuses",
+			ExpectedCode: http.StatusOK,
+			Gzip:         true,
+		},
+		{
+			Name:         "service-status-pagination",
+			Path:         "/api/v1/services/core_frontend/statuses?page=1&pageSize=20",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "service-status-for-invalid-key",
+			Path:         "/api/v1/services/invalid_key/statuses",
+			ExpectedCode: http.StatusNotFound,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			if scenario.Gzip {
+				request.Header.Set("Accept-Encoding", "gzip")
+			}
+			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)
+			}
+		})
+	}
+}
+
+func TestServiceStatuses(t *testing.T) {
+	defer storage.Get().Clear()
+	defer cache.Clear()
+	firstResult := &testSuccessfulResult
+	secondResult := &testUnsuccessfulResult
+	storage.Get().Insert(&testService, firstResult)
+	storage.Get().Insert(&testService, 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)
+
+	type Scenario struct {
+		Name         string
+		Path         string
+		ExpectedCode int
+		ExpectedBody string
+	}
+	scenarios := []Scenario{
+		{
+			Name:         "no-pagination",
+			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":[]}]`,
+		},
+		{
+			Name:         "pagination-first-result",
+			Path:         "/api/v1/services/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":[]}]`,
+		},
+		{
+			Name:         "pagination-second-result",
+			Path:         "/api/v1/services/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":[]}]`,
+		},
+		{
+			Name:         "pagination-no-results",
+			Path:         "/api/v1/services/statuses?page=5&pageSize=20",
+			ExpectedCode: http.StatusOK,
+			ExpectedBody: `[{"name":"name","group":"group","key":"group_name","results":[],"events":[]}]`,
+		},
+		{
+			Name:         "invalid-pagination-should-fall-back-to-default",
+			Path:         "/api/v1/services/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":[]}]`,
+		},
+	}
+
+	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)
+			}
+			output := responseRecorder.Body.String()
+			if output != scenario.ExpectedBody {
+				t.Errorf("expected:\n %s\n\ngot:\n %s", scenario.ExpectedBody, output)
+			}
+		})
+	}
+}

controller/handler/spa.go

@@ -0,0 +1,27 @@
+package handler
+
+import (
+	"html/template"
+	"log"
+	"net/http"
+
+	"github.com/TwinProduction/gatus/config"
+)
+
+func SinglePageApplication(staticFolder string, ui *config.UIConfig) http.HandlerFunc {
+	return func(writer http.ResponseWriter, request *http.Request) {
+		t, err := template.ParseFiles(staticFolder + "/index.html")
+		if err != nil {
+			log.Println("[handler][SinglePageApplication] Failed to parse template:", err.Error())
+			http.ServeFile(writer, request, staticFolder+"/index.html")
+			return
+		}
+		writer.Header().Set("Content-Type", "text/html")
+		err = t.Execute(writer, ui)
+		if err != nil {
+			log.Println("[handler][SinglePageApplication] Failed to parse template:", err.Error())
+			http.ServeFile(writer, request, staticFolder+"/index.html")
+			return
+		}
+	}
+}

controller/handler/spa_test.go

@@ -0,0 +1,65 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/TwinProduction/gatus/config"
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gatus/watchdog"
+)
+
+func TestSinglePageApplication(t *testing.T) {
+	defer storage.Get().Clear()
+	defer cache.Clear()
+	cfg := &config.Config{
+		Metrics: true,
+		Services: []*core.Service{
+			{
+				Name:  "frontend",
+				Group: "core",
+			},
+			{
+				Name:  "backend",
+				Group: "core",
+			},
+		},
+	}
+	watchdog.UpdateServiceStatuses(cfg.Services[0], &core.Result{Success: true, Duration: time.Millisecond, Timestamp: time.Now()})
+	watchdog.UpdateServiceStatuses(cfg.Services[1], &core.Result{Success: false, Duration: time.Second, Timestamp: time.Now()})
+	router := CreateRouter("../../web/static", cfg.Security, nil, cfg.Metrics)
+	type Scenario struct {
+		Name         string
+		Path         string
+		ExpectedCode int
+		Gzip         bool
+	}
+	scenarios := []Scenario{
+		{
+			Name:         "frontend-home",
+			Path:         "/",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "frontend-service",
+			Path:         "/services/core_frontend",
+			ExpectedCode: http.StatusOK,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			if scenario.Gzip {
+				request.Header.Set("Accept-Encoding", "gzip")
+			}
+			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)
+			}
+		})
+	}
+}

controller/handler/util.go

@@ -0,0 +1,48 @@
+package handler
+
+import (
+	"net/http"
+	"strconv"
+
+	"github.com/TwinProduction/gatus/storage/store/common"
+)
+
+const (
+	// DefaultPage is the default page to use if none is specified or an invalid value is provided
+	DefaultPage = 1
+
+	// DefaultPageSize is the default page siZE to use if none is specified or an invalid value is provided
+	DefaultPageSize = 20
+
+	// MaximumPageSize is the maximum page size allowed
+	MaximumPageSize = common.MaximumNumberOfResults
+)
+
+func extractPageAndPageSizeFromRequest(r *http.Request) (page int, pageSize int) {
+	var err error
+	if pageParameter := r.URL.Query().Get("page"); len(pageParameter) == 0 {
+		page = DefaultPage
+	} else {
+		page, err = strconv.Atoi(pageParameter)
+		if err != nil {
+			page = DefaultPage
+		}
+		if page < 1 {
+			page = DefaultPage
+		}
+	}
+	if pageSizeParameter := r.URL.Query().Get("pageSize"); len(pageSizeParameter) == 0 {
+		pageSize = DefaultPageSize
+	} else {
+		pageSize, err = strconv.Atoi(pageSizeParameter)
+		if err != nil {
+			pageSize = DefaultPageSize
+		}
+		if pageSize > MaximumPageSize {
+			pageSize = MaximumPageSize
+		} else if pageSize < 1 {
+			pageSize = DefaultPageSize
+		}
+	}
+	return
+}

controller/handler/util_test.go

@@ -0,0 +1,67 @@
+package handler
+
+import (
+	"fmt"
+	"net/http"
+	"testing"
+)
+
+func TestExtractPageAndPageSizeFromRequest(t *testing.T) {
+	type Scenario struct {
+		Name             string
+		Page             string
+		PageSize         string
+		ExpectedPage     int
+		ExpectedPageSize int
+	}
+	scenarios := []Scenario{
+		{
+			Page:             "1",
+			PageSize:         "20",
+			ExpectedPage:     1,
+			ExpectedPageSize: 20,
+		},
+		{
+			Page:             "2",
+			PageSize:         "10",
+			ExpectedPage:     2,
+			ExpectedPageSize: 10,
+		},
+		{
+			Page:             "2",
+			PageSize:         "10",
+			ExpectedPage:     2,
+			ExpectedPageSize: 10,
+		},
+		{
+			Page:             "1",
+			PageSize:         "999999",
+			ExpectedPage:     1,
+			ExpectedPageSize: MaximumPageSize,
+		},
+		{
+			Page:             "-1",
+			PageSize:         "-1",
+			ExpectedPage:     DefaultPage,
+			ExpectedPageSize: DefaultPageSize,
+		},
+		{
+			Page:             "invalid",
+			PageSize:         "invalid",
+			ExpectedPage:     DefaultPage,
+			ExpectedPageSize: DefaultPageSize,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run("page-"+scenario.Page+"-pageSize-"+scenario.PageSize, func(t *testing.T) {
+			request, _ := http.NewRequest("GET", fmt.Sprintf("/api/v1/statuses?page=%s&pageSize=%s", scenario.Page, scenario.PageSize), nil)
+			actualPage, actualPageSize := extractPageAndPageSizeFromRequest(request)
+			if actualPage != scenario.ExpectedPage {
+				t.Errorf("expected %d, got %d", scenario.ExpectedPage, actualPage)
+			}
+			if actualPageSize != scenario.ExpectedPageSize {
+				t.Errorf("expected %d, got %d", scenario.ExpectedPageSize, actualPageSize)
+			}
+		})
+	}
+}

core/alert.go

@@ -1,60 +0,0 @@
-package core
-
-// Alert is the service's alert configuration
-type Alert struct {
-	// Type of alert
-	Type AlertType `yaml:"type"`
-
-	// Enabled defines whether or not the alert is enabled
-	Enabled bool `yaml:"enabled"`
-
-	// FailureThreshold is the number of failures in a row needed before triggering the alert
-	FailureThreshold int `yaml:"failure-threshold"`
-
-	// Description of the alert. Will be included in the alert sent.
-	Description string `yaml:"description"`
-
-	// SendOnResolved defines whether to send a second notification when the issue has been resolved
-	SendOnResolved bool `yaml:"send-on-resolved"`
-
-	// SuccessThreshold defines how many successful executions must happen in a row before an ongoing incident is marked as resolved
-	SuccessThreshold int `yaml:"success-threshold"`
-
-	// ResolveKey is an optional field that is used by some providers (i.e. PagerDuty's dedup_key) to resolve
-	// ongoing/triggered incidents
-	ResolveKey string
-
-	// 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.
-	//
-	// This value should only be modified if the provider.AlertProvider's Send function does not return an error for an
-	// alert that hasn't been triggered yet. This doubles as a lazy retry. The reason why this behavior isn't also
-	// 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
-}
-
-// AlertType is the type of the alert.
-// The value will generally be the name of the alert provider
-type AlertType string
-
-const (
-	// SlackAlert is the AlertType for the slack alerting provider
-	SlackAlert AlertType = "slack"
-
-	// MattermostAlert is the AlertType for the mattermost alerting provider
-	MattermostAlert AlertType = "mattermost"
-
-	// MessagebirdAlert is the AlertType for the messagebird alerting provider
-	MessagebirdAlert AlertType = "messagebird"
-
-	// PagerDutyAlert is the AlertType for the pagerduty alerting provider
-	PagerDutyAlert AlertType = "pagerduty"
-
-	// TwilioAlert is the AlertType for the twilio alerting provider
-	TwilioAlert AlertType = "twilio"
-
-	// CustomAlert is the AlertType for the custom alerting provider
-	CustomAlert AlertType = "custom"
-)

core/condition.go

@@ -23,7 +23,7 @@ const (
 
 	// DNSRCodePlaceholder is a place holder for DNS_RCODE
 	//
-	// Values that could be NOERROR, FORMERR, SERVFAIL, NXDOMAIN, NOTIMP and REFUSED
+	// Values that could replace the placeholder: NOERROR, FORMERR, SERVFAIL, NXDOMAIN, NOTIMP, REFUSED
 	DNSRCodePlaceholder = "[DNS_RCODE]"
 
 	// ResponseTimePlaceholder is a placeholder for the request response time, in milliseconds.
@@ -51,14 +51,19 @@ const (
 	// Usage: len([BODY].articles) == 10, len([BODY].name) > 5
 	LengthFunctionPrefix = "len("
 
+	// HasFunctionPrefix is the prefix for the has function
+	//
+	// Usage: has([BODY].errors) == true
+	HasFunctionPrefix = "has("
+
 	// PatternFunctionPrefix is the prefix for the pattern function
 	//
-	// Usage: pat(192.168.*.*)
+	// Usage: [IP] == pat(192.168.*.*)
 	PatternFunctionPrefix = "pat("
 
 	// AnyFunctionPrefix is the prefix for the any function
 	//
-	// Usage: any(1.1.1.1, 1.0.0.1)
+	// Usage: [IP] == any(1.1.1.1, 1.0.0.1)
 	AnyFunctionPrefix = "any("
 
 	// FunctionSuffix is the suffix for all functions
@@ -66,54 +71,62 @@ const (
 
 	// InvalidConditionElementSuffix is the suffix that will be appended to an invalid condition
 	InvalidConditionElementSuffix = "(INVALID)"
+
+	// maximumLengthBeforeTruncatingWhenComparedWithPattern is the maximum length an element being compared to a
+	// pattern can have.
+	//
+	// This is only used for aesthetic purposes; it does not influence whether the condition evaluation results in a
+	// success or a failure
+	maximumLengthBeforeTruncatingWhenComparedWithPattern = 25
 )
 
 // Condition is a condition that needs to be met in order for a Service to be considered healthy.
 type Condition string
 
 // evaluate the Condition with the Result of the health check
-func (c Condition) evaluate(result *Result) bool {
+// TODO: Add a mandatory space between each operators (e.g. " == " instead of "==") (BREAKING CHANGE)
+func (c Condition) evaluate(result *Result, dontResolveFailedConditions bool) bool {
 	condition := string(c)
 	success := false
 	conditionToDisplay := condition
 	if strings.Contains(condition, "==") {
 		parameters, resolvedParameters := sanitizeAndResolve(strings.Split(condition, "=="), result)
 		success = isEqual(resolvedParameters[0], resolvedParameters[1])
-		if !success {
+		if !success && !dontResolveFailedConditions {
 			conditionToDisplay = prettify(parameters, resolvedParameters, "==")
 		}
 	} else if strings.Contains(condition, "!=") {
 		parameters, resolvedParameters := sanitizeAndResolve(strings.Split(condition, "!="), result)
 		success = !isEqual(resolvedParameters[0], resolvedParameters[1])
-		if !success {
+		if !success && !dontResolveFailedConditions {
 			conditionToDisplay = prettify(parameters, resolvedParameters, "!=")
 		}
 	} else if strings.Contains(condition, "<=") {
 		parameters, resolvedParameters := sanitizeAndResolveNumerical(strings.Split(condition, "<="), result)
 		success = resolvedParameters[0] <= resolvedParameters[1]
-		if !success {
+		if !success && !dontResolveFailedConditions {
 			conditionToDisplay = prettifyNumericalParameters(parameters, resolvedParameters, "<=")
 		}
 	} else if strings.Contains(condition, ">=") {
 		parameters, resolvedParameters := sanitizeAndResolveNumerical(strings.Split(condition, ">="), result)
 		success = resolvedParameters[0] >= resolvedParameters[1]
-		if !success {
+		if !success && !dontResolveFailedConditions {
 			conditionToDisplay = prettifyNumericalParameters(parameters, resolvedParameters, ">=")
 		}
 	} else if strings.Contains(condition, ">") {
 		parameters, resolvedParameters := sanitizeAndResolveNumerical(strings.Split(condition, ">"), result)
 		success = resolvedParameters[0] > resolvedParameters[1]
-		if !success {
+		if !success && !dontResolveFailedConditions {
 			conditionToDisplay = prettifyNumericalParameters(parameters, resolvedParameters, ">")
 		}
 	} else if strings.Contains(condition, "<") {
 		parameters, resolvedParameters := sanitizeAndResolveNumerical(strings.Split(condition, "<"), result)
 		success = resolvedParameters[0] < resolvedParameters[1]
-		if !success {
+		if !success && !dontResolveFailedConditions {
 			conditionToDisplay = prettifyNumericalParameters(parameters, resolvedParameters, "<")
 		}
 	} else {
-		result.Errors = append(result.Errors, fmt.Sprintf("invalid condition '%s' has been provided", condition))
+		result.AddError(fmt.Sprintf("invalid condition '%s' has been provided", condition))
 		return false
 	}
 	if !success {
@@ -123,6 +136,12 @@ func (c Condition) evaluate(result *Result) bool {
 	return success
 }
 
+// hasBodyPlaceholder checks whether the condition has a BodyPlaceholder
+// Used for determining whether the response body should be read or not
+func (c Condition) hasBodyPlaceholder() bool {
+	return strings.Contains(string(c), BodyPlaceholder)
+}
+
 // isEqual compares two strings.
 //
 // Supports the pattern and the any functions.
@@ -181,7 +200,7 @@ func isEqual(first, second string) bool {
 func sanitizeAndResolve(elements []string, result *Result) ([]string, []string) {
 	parameters := make([]string, len(elements))
 	resolvedParameters := make([]string, len(elements))
-	body := strings.TrimSpace(string(result.Body))
+	body := strings.TrimSpace(string(result.body))
 	for i, element := range elements {
 		element = strings.TrimSpace(element)
 		parameters[i] = element
@@ -203,26 +222,39 @@ func sanitizeAndResolve(elements []string, result *Result) ([]string, []string)
 		default:
 			// if contains the BodyPlaceholder, then evaluate json path
 			if strings.Contains(element, BodyPlaceholder) {
-				wantLength := false
+				checkingForLength := false
+				checkingForExistence := false
 				if strings.HasPrefix(element, LengthFunctionPrefix) && strings.HasSuffix(element, FunctionSuffix) {
-					wantLength = true
+					checkingForLength = true
 					element = strings.TrimSuffix(strings.TrimPrefix(element, LengthFunctionPrefix), FunctionSuffix)
 				}
-				resolvedElement, resolvedElementLength, err := jsonpath.Eval(strings.TrimPrefix(element, BodyPlaceholder+"."), result.Body)
-				if err != nil {
-					if err.Error() != "unexpected end of JSON input" {
-						result.Errors = append(result.Errors, err.Error())
-					}
-					if wantLength {
-						element = LengthFunctionPrefix + element + FunctionSuffix + " " + InvalidConditionElementSuffix
+				if strings.HasPrefix(element, HasFunctionPrefix) && strings.HasSuffix(element, FunctionSuffix) {
+					checkingForExistence = true
+					element = strings.TrimSuffix(strings.TrimPrefix(element, HasFunctionPrefix), FunctionSuffix)
+				}
+				resolvedElement, resolvedElementLength, err := jsonpath.Eval(strings.TrimPrefix(strings.TrimPrefix(element, BodyPlaceholder), "."), result.body)
+				if checkingForExistence {
+					if err != nil {
+						element = "false"
 					} else {
-						element = element + " " + InvalidConditionElementSuffix
+						element = "true"
 					}
 				} else {
-					if wantLength {
-						element = strconv.Itoa(resolvedElementLength)
+					if err != nil {
+						if err.Error() != "unexpected end of JSON input" {
+							result.AddError(err.Error())
+						}
+						if checkingForLength {
+							element = LengthFunctionPrefix + element + FunctionSuffix + " " + InvalidConditionElementSuffix
+						} else {
+							element = element + " " + InvalidConditionElementSuffix
+						}
 					} else {
-						element = resolvedElement
+						if checkingForLength {
+							element = strconv.Itoa(resolvedElementLength)
+						} else {
+							element = resolvedElement
+						}
 					}
 				}
 			}
@@ -258,6 +290,13 @@ func prettify(parameters []string, resolvedParameters []string, operator string)
 	if strings.HasSuffix(resolvedParameters[0], InvalidConditionElementSuffix) || strings.HasSuffix(resolvedParameters[1], InvalidConditionElementSuffix) {
 		return resolvedParameters[0] + " " + operator + " " + resolvedParameters[1]
 	}
+	// If using the pattern function, truncate the parameter it's being compared to if said parameter is long enough
+	if strings.HasPrefix(parameters[0], PatternFunctionPrefix) && strings.HasSuffix(parameters[0], FunctionSuffix) && len(resolvedParameters[1]) > maximumLengthBeforeTruncatingWhenComparedWithPattern {
+		resolvedParameters[1] = fmt.Sprintf("%.25s...(truncated)", resolvedParameters[1])
+	}
+	if strings.HasPrefix(parameters[1], PatternFunctionPrefix) && strings.HasSuffix(parameters[1], FunctionSuffix) && len(resolvedParameters[0]) > maximumLengthBeforeTruncatingWhenComparedWithPattern {
+		resolvedParameters[0] = fmt.Sprintf("%.25s...(truncated)", resolvedParameters[0])
+	}
 	// First element is a placeholder
 	if parameters[0] != resolvedParameters[0] && parameters[1] == resolvedParameters[1] {
 		return parameters[0] + " (" + resolvedParameters[0] + ") " + operator + " " + parameters[1]

core/condition_bench_test.go

@@ -5,8 +5,8 @@ import "testing"
 func BenchmarkCondition_evaluateWithBodyStringAny(b *testing.B) {
 	condition := Condition("[BODY].name == any(john.doe, jane.doe)")
 	for n := 0; n < b.N; n++ {
-		result := &Result{Body: []byte("{\"name\": \"john.doe\"}")}
-		condition.evaluate(result)
+		result := &Result{body: []byte("{\"name\": \"john.doe\"}")}
+		condition.evaluate(result, false)
 	}
 	b.ReportAllocs()
 }
@@ -14,8 +14,8 @@ func BenchmarkCondition_evaluateWithBodyStringAny(b *testing.B) {
 func BenchmarkCondition_evaluateWithBodyStringAnyFailure(b *testing.B) {
 	condition := Condition("[BODY].name == any(john.doe, jane.doe)")
 	for n := 0; n < b.N; n++ {
-		result := &Result{Body: []byte("{\"name\": \"bob.doe\"}")}
-		condition.evaluate(result)
+		result := &Result{body: []byte("{\"name\": \"bob.doe\"}")}
+		condition.evaluate(result, false)
 	}
 	b.ReportAllocs()
 }
@@ -23,8 +23,8 @@ func BenchmarkCondition_evaluateWithBodyStringAnyFailure(b *testing.B) {
 func BenchmarkCondition_evaluateWithBodyString(b *testing.B) {
 	condition := Condition("[BODY].name == john.doe")
 	for n := 0; n < b.N; n++ {
-		result := &Result{Body: []byte("{\"name\": \"john.doe\"}")}
-		condition.evaluate(result)
+		result := &Result{body: []byte("{\"name\": \"john.doe\"}")}
+		condition.evaluate(result, false)
 	}
 	b.ReportAllocs()
 }
@@ -32,8 +32,17 @@ func BenchmarkCondition_evaluateWithBodyString(b *testing.B) {
 func BenchmarkCondition_evaluateWithBodyStringFailure(b *testing.B) {
 	condition := Condition("[BODY].name == john.doe")
 	for n := 0; n < b.N; n++ {
-		result := &Result{Body: []byte("{\"name\": \"bob.doe\"}")}
-		condition.evaluate(result)
+		result := &Result{body: []byte("{\"name\": \"bob.doe\"}")}
+		condition.evaluate(result, false)
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkCondition_evaluateWithBodyStringFailureInvalidPath(b *testing.B) {
+	condition := Condition("[BODY].user.name == bob.doe")
+	for n := 0; n < b.N; n++ {
+		result := &Result{body: []byte("{\"name\": \"bob.doe\"}")}
+		condition.evaluate(result, false)
 	}
 	b.ReportAllocs()
 }
@@ -41,8 +50,8 @@ func BenchmarkCondition_evaluateWithBodyStringFailure(b *testing.B) {
 func BenchmarkCondition_evaluateWithBodyStringLen(b *testing.B) {
 	condition := Condition("len([BODY].name) == 8")
 	for n := 0; n < b.N; n++ {
-		result := &Result{Body: []byte("{\"name\": \"john.doe\"}")}
-		condition.evaluate(result)
+		result := &Result{body: []byte("{\"name\": \"john.doe\"}")}
+		condition.evaluate(result, false)
 	}
 	b.ReportAllocs()
 }
@@ -50,8 +59,8 @@ func BenchmarkCondition_evaluateWithBodyStringLen(b *testing.B) {
 func BenchmarkCondition_evaluateWithBodyStringLenFailure(b *testing.B) {
 	condition := Condition("len([BODY].name) == 8")
 	for n := 0; n < b.N; n++ {
-		result := &Result{Body: []byte("{\"name\": \"bob.doe\"}")}
-		condition.evaluate(result)
+		result := &Result{body: []byte("{\"name\": \"bob.doe\"}")}
+		condition.evaluate(result, false)
 	}
 	b.ReportAllocs()
 }
@@ -60,7 +69,7 @@ func BenchmarkCondition_evaluateWithStatus(b *testing.B) {
 	condition := Condition("[STATUS] == 200")
 	for n := 0; n < b.N; n++ {
 		result := &Result{HTTPStatus: 200}
-		condition.evaluate(result)
+		condition.evaluate(result, false)
 	}
 	b.ReportAllocs()
 }
@@ -69,7 +78,7 @@ func BenchmarkCondition_evaluateWithStatusFailure(b *testing.B) {
 	condition := Condition("[STATUS] == 200")
 	for n := 0; n < b.N; n++ {
 		result := &Result{HTTPStatus: 400}
-		condition.evaluate(result)
+		condition.evaluate(result, false)
 	}
 	b.ReportAllocs()
 }

core/dns.go

@@ -29,16 +29,17 @@ type DNS struct {
 	QueryName string `yaml:"query-name"`
 }
 
-func (d *DNS) validateAndSetDefault() {
+func (d *DNS) validateAndSetDefault() error {
 	if len(d.QueryName) == 0 {
-		panic(ErrDNSWithNoQueryName)
+		return ErrDNSWithNoQueryName
 	}
 	if !strings.HasSuffix(d.QueryName, ".") {
 		d.QueryName += "."
 	}
 	if _, ok := dns.StringToType[d.QueryType]; !ok {
-		panic(ErrDNSWithInvalidQueryType)
+		return ErrDNSWithInvalidQueryType
 	}
+	return nil
 }
 
 func (d *DNS) query(url string, result *Result) {
@@ -51,7 +52,7 @@ func (d *DNS) query(url string, result *Result) {
 	m.SetQuestion(d.QueryName, queryType)
 	r, _, err := c.Exchange(m, url)
 	if err != nil {
-		result.Errors = append(result.Errors, err.Error())
+		result.AddError(err.Error())
 		return
 	}
 	result.Connected = true
@@ -60,26 +61,26 @@ func (d *DNS) query(url string, result *Result) {
 		switch rr.Header().Rrtype {
 		case dns.TypeA:
 			if a, ok := rr.(*dns.A); ok {
-				result.Body = []byte(a.A.String())
+				result.body = []byte(a.A.String())
 			}
 		case dns.TypeAAAA:
 			if aaaa, ok := rr.(*dns.AAAA); ok {
-				result.Body = []byte(aaaa.AAAA.String())
+				result.body = []byte(aaaa.AAAA.String())
 			}
 		case dns.TypeCNAME:
 			if cname, ok := rr.(*dns.CNAME); ok {
-				result.Body = []byte(cname.Target)
+				result.body = []byte(cname.Target)
 			}
 		case dns.TypeMX:
 			if mx, ok := rr.(*dns.MX); ok {
-				result.Body = []byte(mx.Mx)
+				result.body = []byte(mx.Mx)
 			}
 		case dns.TypeNS:
 			if ns, ok := rr.(*dns.NS); ok {
-				result.Body = []byte(ns.Ns)
+				result.body = []byte(ns.Ns)
 			}
 		default:
-			result.Body = []byte("query type is not supported yet")
+			result.body = []byte("query type is not supported yet")
 		}
 	}
 }

core/dns_test.go

@@ -91,12 +91,12 @@ func TestIntegrationQuery(t *testing.T) {
 
 			if test.inputDNS.QueryType == "NS" {
 				// Because there are often multiple nameservers backing a single domain, we'll only look at the suffix
-				if !pattern.Match(test.expectedBody, string(result.Body)) {
-					t.Errorf("got %s, expected result %s,", string(result.Body), test.expectedBody)
+				if !pattern.Match(test.expectedBody, string(result.body)) {
+					t.Errorf("got %s, expected result %s,", string(result.body), test.expectedBody)
 				}
 			} else {
-				if string(result.Body) != test.expectedBody {
-					t.Errorf("got %s, expected result %s,", string(result.Body), test.expectedBody)
+				if string(result.body) != test.expectedBody {
+					t.Errorf("got %s, expected result %s,", string(result.body), test.expectedBody)
 				}
 			}
 		})
@@ -109,8 +109,10 @@ func TestService_ValidateAndSetDefaultsWithNoDNSQueryName(t *testing.T) {
 		QueryType: "A",
 		QueryName: "",
 	}
-	dns.validateAndSetDefault()
-	t.Fatal("Should've panicked because service`s dns didn't have a query name, which is a mandatory field for dns")
+	err := dns.validateAndSetDefault()
+	if err == nil {
+		t.Fatal("Should've returned an error because service`s dns didn't have a query name, which is a mandatory field for dns")
+	}
 }
 
 func TestService_ValidateAndSetDefaultsWithInvalidDNSQueryType(t *testing.T) {
@@ -119,6 +121,8 @@ func TestService_ValidateAndSetDefaultsWithInvalidDNSQueryType(t *testing.T) {
 		QueryType: "B",
 		QueryName: "example.com",
 	}
-	dns.validateAndSetDefault()
-	t.Fatal("Should've panicked because service`s dns query type is invalid, it needs to be a valid query name like A, AAAA, CNAME...")
+	err := dns.validateAndSetDefault()
+	if err == nil {
+		t.Fatal("Should've returned an error because service`s dns query type is invalid, it needs to be a valid query name like A, AAAA, CNAME...")
+	}
 }

core/event.go

@@ -0,0 +1,37 @@
+package core
+
+import "time"
+
+// Event is something that happens at a specific time
+type Event struct {
+	// Type is the kind of event
+	Type EventType `json:"type"`
+
+	// Timestamp is the moment at which the event happened
+	Timestamp time.Time `json:"timestamp"`
+}
+
+// EventType is, uh, the types of events?
+type EventType string
+
+var (
+	// EventStart is a type of event that represents when a service starts being monitored
+	EventStart EventType = "START"
+
+	// EventHealthy is a type of event that represents a service passing all of its conditions
+	EventHealthy EventType = "HEALTHY"
+
+	// EventUnhealthy is a type of event that represents a service failing one or more of its conditions
+	EventUnhealthy EventType = "UNHEALTHY"
+)
+
+// NewEventFromResult creates an Event from a Result
+func NewEventFromResult(result *Result) *Event {
+	event := &Event{Timestamp: result.Timestamp}
+	if result.Success {
+		event.Type = EventHealthy
+	} else {
+		event.Type = EventUnhealthy
+	}
+	return event
+}

core/event_test.go

@@ -0,0 +1,12 @@
+package core
+
+import "testing"
+
+func TestNewEventFromResult(t *testing.T) {
+	if event := NewEventFromResult(&Result{Success: true}); event.Type != EventHealthy {
+		t.Error("expected event.Type to be EventHealthy")
+	}
+	if event := NewEventFromResult(&Result{Success: false}); event.Type != EventUnhealthy {
+		t.Error("expected event.Type to be EventUnhealthy")
+	}
+}

core/result.go

@@ -12,10 +12,7 @@ type Result struct {
 	// DNSRCode is the response code of a DNS query in a human readable format
 	DNSRCode string `json:"-"`
 
-	// Body is the response body
-	Body []byte `json:"-"`
-
-	// Hostname extracted from the Service URL
+	// Hostname extracted from Service.URL
 	Hostname string `json:"hostname"`
 
 	// IP resolved from the Service URL
@@ -31,7 +28,7 @@ type Result struct {
 	Errors []string `json:"errors"`
 
 	// ConditionResults results of the service's conditions
-	ConditionResults []*ConditionResult `json:"condition-results"`
+	ConditionResults []*ConditionResult `json:"conditionResults"`
 
 	// Success whether the result signifies a success or not
 	Success bool `json:"success"`
@@ -41,4 +38,23 @@ type Result struct {
 
 	// CertificateExpiration is the duration before the certificate expires
 	CertificateExpiration time.Duration `json:"-"`
+
+	// body is the response body
+	//
+	// Note that this variable is only used during the evaluation of a service's health.
+	// This means that the call Service.EvaluateHealth both populates the body (if necessary)
+	// and sets it to nil after the evaluation has been completed.
+	body []byte
+}
+
+// AddError adds an error to the result's list of errors.
+// It also ensures that there are no duplicates.
+func (r *Result) AddError(error string) {
+	for _, resultError := range r.Errors {
+		if resultError == error {
+			// If the error already exists, don't add it
+			return
+		}
+	}
+	r.Errors = append(r.Errors, error)
 }

core/result_test.go

@@ -0,0 +1,21 @@
+package core
+
+import (
+	"testing"
+)
+
+func TestResult_AddError(t *testing.T) {
+	result := &Result{}
+	result.AddError("potato")
+	if len(result.Errors) != 1 {
+		t.Error("should've had 1 error")
+	}
+	result.AddError("potato")
+	if len(result.Errors) != 1 {
+		t.Error("should've still had 1 error, because a duplicate error was added")
+	}
+	result.AddError("tomato")
+	if len(result.Errors) != 2 {
+		t.Error("should've had 2 error")
+	}
+}

core/service-status.go

@@ -1,36 +0,0 @@
-package core
-
-// ServiceStatus contains the evaluation Results of a Service
-type ServiceStatus struct {
-	// Name of the service
-	Name string `json:"name,omitempty"`
-
-	// Group the service is a part of. Used for grouping multiple services together on the front end.
-	Group string `json:"group,omitempty"`
-
-	// Results is the list of service evaluation results
-	Results []*Result `json:"results"`
-
-	// Uptime information on the service's uptime
-	Uptime *Uptime `json:"uptime"`
-}
-
-// NewServiceStatus creates a new ServiceStatus
-func NewServiceStatus(service *Service) *ServiceStatus {
-	return &ServiceStatus{
-		Name:    service.Name,
-		Group:   service.Group,
-		Results: make([]*Result, 0),
-		Uptime:  NewUptime(),
-	}
-}
-
-// AddResult adds a Result to ServiceStatus.Results and makes sure that there are
-// no more than 20 results in the Results slice
-func (ss *ServiceStatus) AddResult(result *Result) {
-	ss.Results = append(ss.Results, result)
-	if len(ss.Results) > 20 {
-		ss.Results = ss.Results[1:]
-	}
-	ss.Uptime.ProcessResult(result)
-}

core/service-status_test.go

@@ -1,28 +0,0 @@
-package core
-
-import (
-	"testing"
-	"time"
-)
-
-func TestNewServiceStatus(t *testing.T) {
-	service := &Service{Name: "name", Group: "group"}
-	serviceStatus := NewServiceStatus(service)
-	if serviceStatus.Name != service.Name {
-		t.Errorf("expected %s, got %s", service.Name, serviceStatus.Name)
-	}
-	if serviceStatus.Group != service.Group {
-		t.Errorf("expected %s, got %s", service.Group, serviceStatus.Group)
-	}
-}
-
-func TestServiceStatus_AddResult(t *testing.T) {
-	service := &Service{Name: "name", Group: "group"}
-	serviceStatus := NewServiceStatus(service)
-	for i := 0; i < 50; i++ {
-		serviceStatus.AddResult(&Result{Timestamp: time.Now()})
-	}
-	if len(serviceStatus.Results) != 20 {
-		t.Errorf("expected serviceStatus.Results to not exceed a length of 20")
-	}
-}

core/service.go

@@ -2,6 +2,7 @@ package core
 
 import (
 	"bytes"
+	"crypto/x509"
 	"encoding/json"
 	"errors"
 	"io/ioutil"
@@ -11,7 +12,10 @@ import (
 	"strings"
 	"time"
 
+	"github.com/TwinProduction/gatus/alerting/alert"
 	"github.com/TwinProduction/gatus/client"
+	"github.com/TwinProduction/gatus/core/ui"
+	"github.com/TwinProduction/gatus/util"
 )
 
 const (
@@ -72,21 +76,32 @@ type Service struct {
 	Conditions []*Condition `yaml:"conditions"`
 
 	// Alerts is the alerting configuration for the service in case of failure
-	Alerts []*Alert `yaml:"alerts"`
+	Alerts []*alert.Alert `yaml:"alerts"`
 
-	// Insecure is whether to skip verifying the server's certificate chain and host name
-	Insecure bool `yaml:"insecure,omitempty"`
+	// ClientConfig is the configuration of the client used to communicate with the service's target
+	ClientConfig *client.Config `yaml:"client"`
+
+	// UIConfig is the configuration for the UI
+	UIConfig *ui.Config `yaml:"ui"`
 
 	// NumberOfFailuresInARow is the number of unsuccessful evaluations in a row
 	NumberOfFailuresInARow int
 
-	// NumberOfFailuresInARow is the number of successful evaluations in a row
+	// NumberOfSuccessesInARow is the number of successful evaluations in a row
 	NumberOfSuccessesInARow int
 }
 
 // ValidateAndSetDefaults validates the service's configuration and sets the default value of fields that have one
-func (service *Service) ValidateAndSetDefaults() {
+func (service *Service) ValidateAndSetDefaults() error {
 	// Set default values
+	if service.ClientConfig == nil {
+		service.ClientConfig = client.GetDefaultConfig()
+	} else {
+		service.ClientConfig.ValidateAndSetDefaults()
+	}
+	if service.UIConfig == nil {
+		service.UIConfig = ui.GetDefaultConfig()
+	}
 	if service.Interval == 0 {
 		service.Interval = 1 * time.Minute
 	}
@@ -105,32 +120,37 @@ func (service *Service) ValidateAndSetDefaults() {
 	if _, contentTypeHeaderExists := service.Headers[ContentTypeHeader]; !contentTypeHeaderExists && service.GraphQL {
 		service.Headers[ContentTypeHeader] = "application/json"
 	}
-	for _, alert := range service.Alerts {
-		if alert.FailureThreshold <= 0 {
-			alert.FailureThreshold = 3
+	for _, serviceAlert := range service.Alerts {
+		if serviceAlert.FailureThreshold <= 0 {
+			serviceAlert.FailureThreshold = 3
 		}
-		if alert.SuccessThreshold <= 0 {
-			alert.SuccessThreshold = 2
+		if serviceAlert.SuccessThreshold <= 0 {
+			serviceAlert.SuccessThreshold = 2
 		}
 	}
 	if len(service.Name) == 0 {
-		panic(ErrServiceWithNoName)
+		return ErrServiceWithNoName
 	}
 	if len(service.URL) == 0 {
-		panic(ErrServiceWithNoURL)
+		return ErrServiceWithNoURL
 	}
 	if len(service.Conditions) == 0 {
-		panic(ErrServiceWithNoCondition)
+		return ErrServiceWithNoCondition
 	}
 	if service.DNS != nil {
-		service.DNS.validateAndSetDefault()
-		return
+		return service.DNS.validateAndSetDefault()
 	}
 	// Make sure that the request can be created
 	_, err := http.NewRequest(service.Method, service.URL, bytes.NewBuffer([]byte(service.Body)))
 	if err != nil {
-		panic(err)
+		return err
 	}
+	return nil
+}
+
+// Key returns the unique key for the Service
+func (service Service) Key() string {
+	return util.ConvertGroupAndServiceToKey(service.Group, service.Name)
 }
 
 // EvaluateHealth sends a request to the service's URL and evaluates the conditions of the service.
@@ -143,44 +163,35 @@ func (service *Service) EvaluateHealth() *Result {
 		result.Success = false
 	}
 	for _, condition := range service.Conditions {
-		success := condition.evaluate(result)
+		success := condition.evaluate(result, service.UIConfig.DontResolveFailedConditions)
 		if !success {
 			result.Success = false
 		}
 	}
 	result.Timestamp = time.Now()
+	// No need to keep the body after the service has been evaluated
+	result.body = nil
+	// Clean up parameters that we don't need to keep in the results
+	if service.UIConfig.HideHostname {
+		result.Hostname = ""
+	}
 	return result
 }
 
-// GetAlertsTriggered returns a slice of alerts that have been triggered
-func (service *Service) GetAlertsTriggered() []Alert {
-	var alerts []Alert
-	if service.NumberOfFailuresInARow == 0 {
-		return alerts
-	}
-	for _, alert := range service.Alerts {
-		if alert.Enabled && alert.FailureThreshold == service.NumberOfFailuresInARow {
-			alerts = append(alerts, *alert)
-			continue
-		}
-	}
-	return alerts
-}
-
 func (service *Service) getIP(result *Result) {
 	if service.DNS != nil {
 		result.Hostname = strings.TrimSuffix(service.URL, ":53")
 	} else {
 		urlObject, err := url.Parse(service.URL)
 		if err != nil {
-			result.Errors = append(result.Errors, err.Error())
+			result.AddError(err.Error())
 			return
 		}
 		result.Hostname = urlObject.Hostname()
 	}
 	ips, err := net.LookupIP(result.Hostname)
 	if err != nil {
-		result.Errors = append(result.Errors, err.Error())
+		result.AddError(err.Error())
 		return
 	}
 	result.IP = ips[0].String()
@@ -190,10 +201,12 @@ func (service *Service) call(result *Result) {
 	var request *http.Request
 	var response *http.Response
 	var err error
+	var certificate *x509.Certificate
 	isServiceDNS := service.DNS != nil
 	isServiceTCP := strings.HasPrefix(service.URL, "tcp://")
 	isServiceICMP := strings.HasPrefix(service.URL, "icmp://")
-	isServiceHTTP := !isServiceDNS && !isServiceTCP && !isServiceICMP
+	isServiceStartTLS := strings.HasPrefix(service.URL, "starttls://")
+	isServiceHTTP := !isServiceDNS && !isServiceTCP && !isServiceICMP && !isServiceStartTLS
 	if isServiceHTTP {
 		request = service.buildHTTPRequest()
 	}
@@ -201,27 +214,39 @@ func (service *Service) call(result *Result) {
 	if isServiceDNS {
 		service.DNS.query(service.URL, result)
 		result.Duration = time.Since(startTime)
-	} else if isServiceTCP {
-		result.Connected = client.CanCreateTCPConnection(strings.TrimPrefix(service.URL, "tcp://"))
-		result.Duration = time.Since(startTime)
-	} else if isServiceICMP {
-		result.Connected, result.Duration = client.Ping(strings.TrimPrefix(service.URL, "icmp://"))
-	} else {
-		response, err = client.GetHTTPClient(service.Insecure).Do(request)
-		result.Duration = time.Since(startTime)
+	} else if isServiceStartTLS {
+		result.Connected, certificate, err = client.CanPerformStartTLS(strings.TrimPrefix(service.URL, "starttls://"), service.ClientConfig)
 		if err != nil {
-			result.Errors = append(result.Errors, err.Error())
+			result.AddError(err.Error())
 			return
 		}
+		result.Duration = time.Since(startTime)
+		result.CertificateExpiration = time.Until(certificate.NotAfter)
+	} else if isServiceTCP {
+		result.Connected = client.CanCreateTCPConnection(strings.TrimPrefix(service.URL, "tcp://"), service.ClientConfig)
+		result.Duration = time.Since(startTime)
+	} else if isServiceICMP {
+		result.Connected, result.Duration = client.Ping(strings.TrimPrefix(service.URL, "icmp://"), service.ClientConfig)
+	} else {
+		response, err = client.GetHTTPClient(service.ClientConfig).Do(request)
+		result.Duration = time.Since(startTime)
+		if err != nil {
+			result.AddError(err.Error())
+			return
+		}
+		defer response.Body.Close()
 		if response.TLS != nil && len(response.TLS.PeerCertificates) > 0 {
-			certificate := response.TLS.PeerCertificates[0]
-			result.CertificateExpiration = certificate.NotAfter.Sub(time.Now())
+			certificate = response.TLS.PeerCertificates[0]
+			result.CertificateExpiration = time.Until(certificate.NotAfter)
 		}
 		result.HTTPStatus = response.StatusCode
 		result.Connected = response.StatusCode > 0
-		result.Body, err = ioutil.ReadAll(response.Body)
-		if err != nil {
-			result.Errors = append(result.Errors, err.Error())
+		// Only read the body if there's a condition that uses the BodyPlaceholder
+		if service.needsToReadBody() {
+			result.body, err = ioutil.ReadAll(response.Body)
+			if err != nil {
+				result.AddError(err.Error())
+			}
 		}
 	}
 }
@@ -246,3 +271,13 @@ func (service *Service) buildHTTPRequest() *http.Request {
 	}
 	return request
 }
+
+// needsToReadBody checks if there's any conditions that requires the response body to be read
+func (service *Service) needsToReadBody() bool {
+	for _, condition := range service.Conditions {
+		if condition.hasBodyPlaceholder() {
+			return true
+		}
+	}
+	return false
+}

core/service_status.go

@@ -0,0 +1,38 @@
+package core
+
+// ServiceStatus contains the evaluation Results of a Service
+type ServiceStatus struct {
+	// Name of the service
+	Name string `json:"name,omitempty"`
+
+	// Group the service is a part of. Used for grouping multiple services together on the front end.
+	Group string `json:"group,omitempty"`
+
+	// Key is the key representing the ServiceStatus
+	Key string `json:"key"`
+
+	// Results is the list of service evaluation results
+	Results []*Result `json:"results"`
+
+	// Events is a list of events
+	Events []*Event `json:"events"`
+
+	// Uptime information on the service's uptime
+	//
+	// Used by the memory store.
+	//
+	// To retrieve the uptime between two time, use store.GetUptimeByKey.
+	Uptime *Uptime `json:"-"`
+}
+
+// NewServiceStatus creates a new ServiceStatus
+func NewServiceStatus(serviceKey, serviceGroup, serviceName string) *ServiceStatus {
+	return &ServiceStatus{
+		Name:    serviceName,
+		Group:   serviceGroup,
+		Key:     serviceKey,
+		Results: make([]*Result, 0),
+		Events:  make([]*Event, 0),
+		Uptime:  NewUptime(),
+	}
+}

core/service_status_test.go

@@ -0,0 +1,19 @@
+package core
+
+import (
+	"testing"
+)
+
+func TestNewServiceStatus(t *testing.T) {
+	service := &Service{Name: "name", Group: "group"}
+	serviceStatus := NewServiceStatus(service.Key(), service.Group, service.Name)
+	if serviceStatus.Name != service.Name {
+		t.Errorf("expected %s, got %s", service.Name, serviceStatus.Name)
+	}
+	if serviceStatus.Group != service.Group {
+		t.Errorf("expected %s, got %s", service.Group, serviceStatus.Group)
+	}
+	if serviceStatus.Key != "group_name" {
+		t.Errorf("expected %s, got %s", "group_name", serviceStatus.Key)
+	}
+}

core/service_test.go

@@ -5,17 +5,33 @@ import (
 	"strings"
 	"testing"
 	"time"
+
+	"github.com/TwinProduction/gatus/alerting/alert"
+	"github.com/TwinProduction/gatus/client"
 )
 
 func TestService_ValidateAndSetDefaults(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
-		Alerts:     []*Alert{{Type: PagerDutyAlert}},
+		Alerts:     []*alert.Alert{{Type: alert.TypePagerDuty}},
 	}
 	service.ValidateAndSetDefaults()
+	if service.ClientConfig == nil {
+		t.Error("client configuration should've been set to the default configuration")
+	} else {
+		if service.ClientConfig.Insecure != client.GetDefaultConfig().Insecure {
+			t.Errorf("Default client configuration should've set Insecure to %v, got %v", client.GetDefaultConfig().Insecure, service.ClientConfig.Insecure)
+		}
+		if service.ClientConfig.IgnoreRedirect != client.GetDefaultConfig().IgnoreRedirect {
+			t.Errorf("Default client configuration should've set IgnoreRedirect to %v, got %v", client.GetDefaultConfig().IgnoreRedirect, service.ClientConfig.IgnoreRedirect)
+		}
+		if service.ClientConfig.Timeout != client.GetDefaultConfig().Timeout {
+			t.Errorf("Default client configuration should've set Timeout to %v, got %v", client.GetDefaultConfig().Timeout, service.ClientConfig.Timeout)
+		}
+	}
 	if service.Method != "GET" {
 		t.Error("Service method should've defaulted to GET")
 	}
@@ -28,7 +44,7 @@ func TestService_ValidateAndSetDefaults(t *testing.T) {
 	if len(service.Alerts) != 1 {
 		t.Error("Service should've had 1 alert")
 	}
-	if service.Alerts[0].Enabled {
+	if service.Alerts[0].IsEnabled() {
 		t.Error("Service alert should've defaulted to disabled")
 	}
 	if service.Alerts[0].SuccessThreshold != 2 {
@@ -39,6 +55,34 @@ func TestService_ValidateAndSetDefaults(t *testing.T) {
 	}
 }
 
+func TestService_ValidateAndSetDefaultsWithClientConfig(t *testing.T) {
+	condition := Condition("[STATUS] == 200")
+	service := Service{
+		Name:       "twinnation-health",
+		URL:        "https://twinnation.org/health",
+		Conditions: []*Condition{&condition},
+		ClientConfig: &client.Config{
+			Insecure:       true,
+			IgnoreRedirect: true,
+			Timeout:        0,
+		},
+	}
+	service.ValidateAndSetDefaults()
+	if service.ClientConfig == nil {
+		t.Error("client configuration should've been set to the default configuration")
+	} else {
+		if !service.ClientConfig.Insecure {
+			t.Error("service.ClientConfig.Insecure should've been set to true")
+		}
+		if !service.ClientConfig.IgnoreRedirect {
+			t.Error("service.ClientConfig.IgnoreRedirect should've been set to true")
+		}
+		if service.ClientConfig.Timeout != client.GetDefaultConfig().Timeout {
+			t.Error("service.ClientConfig.Timeout should've been set to 10s, because the timeout value entered is not set or invalid")
+		}
+	}
+}
+
 func TestService_ValidateAndSetDefaultsWithNoName(t *testing.T) {
 	defer func() { recover() }()
 	condition := Condition("[STATUS] == 200")
@@ -47,8 +91,10 @@ func TestService_ValidateAndSetDefaultsWithNoName(t *testing.T) {
 		URL:        "http://example.com",
 		Conditions: []*Condition{&condition},
 	}
-	service.ValidateAndSetDefaults()
-	t.Fatal("Should've panicked because service didn't have a name, which is a mandatory field")
+	err := service.ValidateAndSetDefaults()
+	if err == nil {
+		t.Fatal("Should've returned an error because service didn't have a name, which is a mandatory field")
+	}
 }
 
 func TestService_ValidateAndSetDefaultsWithNoUrl(t *testing.T) {
@@ -59,8 +105,10 @@ func TestService_ValidateAndSetDefaultsWithNoUrl(t *testing.T) {
 		URL:        "",
 		Conditions: []*Condition{&condition},
 	}
-	service.ValidateAndSetDefaults()
-	t.Fatal("Should've panicked because service didn't have an url, which is a mandatory field")
+	err := service.ValidateAndSetDefaults()
+	if err == nil {
+		t.Fatal("Should've returned an error because service didn't have an url, which is a mandatory field")
+	}
 }
 
 func TestService_ValidateAndSetDefaultsWithNoConditions(t *testing.T) {
@@ -70,8 +118,10 @@ func TestService_ValidateAndSetDefaultsWithNoConditions(t *testing.T) {
 		URL:        "http://example.com",
 		Conditions: nil,
 	}
-	service.ValidateAndSetDefaults()
-	t.Fatal("Should've panicked because service didn't have at least 1 condition")
+	err := service.ValidateAndSetDefaults()
+	if err == nil {
+		t.Fatal("Should've returned an error because service didn't have at least 1 condition")
+	}
 }
 
 func TestService_ValidateAndSetDefaultsWithDNS(t *testing.T) {
@@ -85,40 +135,19 @@ func TestService_ValidateAndSetDefaultsWithDNS(t *testing.T) {
 		},
 		Conditions: []*Condition{&conditionSuccess},
 	}
-	service.ValidateAndSetDefaults()
+	err := service.ValidateAndSetDefaults()
+	if err != nil {
+
+	}
 	if service.DNS.QueryName != "example.com." {
 		t.Error("Service.dns.query-name should be formatted with . suffix")
 	}
 }
 
-func TestService_GetAlertsTriggered(t *testing.T) {
-	condition := Condition("[STATUS] == 200")
-	service := Service{
-		Name:       "TwiNNatioN",
-		URL:        "https://twinnation.org/health",
-		Conditions: []*Condition{&condition},
-		Alerts:     []*Alert{{Type: PagerDutyAlert, Enabled: true}},
-	}
-	service.ValidateAndSetDefaults()
-	if service.NumberOfFailuresInARow != 0 {
-		t.Error("Service.NumberOfFailuresInARow should start with 0")
-	}
-	if service.NumberOfSuccessesInARow != 0 {
-		t.Error("Service.NumberOfSuccessesInARow should start with 0")
-	}
-	if len(service.GetAlertsTriggered()) > 0 {
-		t.Error("No alerts should've been triggered, because service.NumberOfFailuresInARow is 0, which is below the failure threshold")
-	}
-	service.NumberOfFailuresInARow = service.Alerts[0].FailureThreshold
-	if len(service.GetAlertsTriggered()) != 1 {
-		t.Error("Alert should've been triggered")
-	}
-}
-
 func TestService_buildHTTPRequest(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 	}
@@ -138,7 +167,7 @@ func TestService_buildHTTPRequest(t *testing.T) {
 func TestService_buildHTTPRequestWithCustomUserAgent(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 		Headers: map[string]string{
@@ -161,7 +190,7 @@ func TestService_buildHTTPRequestWithCustomUserAgent(t *testing.T) {
 func TestService_buildHTTPRequestWithHostHeader(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Method:     "POST",
 		Conditions: []*Condition{&condition},
@@ -182,13 +211,13 @@ func TestService_buildHTTPRequestWithHostHeader(t *testing.T) {
 func TestService_buildHTTPRequestWithGraphQLEnabled(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-graphql",
 		URL:        "https://twinnation.org/graphql",
 		Method:     "POST",
 		Conditions: []*Condition{&condition},
 		GraphQL:    true,
 		Body: `{
-  user(gender: "female") {
+  users(gender: "female") {
     id
     name
     gender
@@ -206,17 +235,19 @@ func TestService_buildHTTPRequestWithGraphQLEnabled(t *testing.T) {
 	}
 	body, _ := ioutil.ReadAll(request.Body)
 	if !strings.HasPrefix(string(body), "{\"query\":") {
-		t.Error("request.Body should've started with '{\"query\":', but it didn't:", string(body))
+		t.Error("request.body should've started with '{\"query\":', but it didn't:", string(body))
 	}
 }
 
 func TestIntegrationEvaluateHealth(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
+	bodyCondition := Condition("[BODY].status == UP")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
-		Conditions: []*Condition{&condition},
+		Conditions: []*Condition{&condition, &bodyCondition},
 	}
+	service.ValidateAndSetDefaults()
 	result := service.EvaluateHealth()
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
@@ -232,10 +263,11 @@ func TestIntegrationEvaluateHealth(t *testing.T) {
 func TestIntegrationEvaluateHealthWithFailure(t *testing.T) {
 	condition := Condition("[STATUS] == 500")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 	}
+	service.ValidateAndSetDefaults()
 	result := service.EvaluateHealth()
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
@@ -252,7 +284,7 @@ func TestIntegrationEvaluateHealthForDNS(t *testing.T) {
 	conditionSuccess := Condition("[DNS_RCODE] == NOERROR")
 	conditionBody := Condition("[BODY] == 93.184.216.34")
 	service := Service{
-		Name: "TwiNNatioN",
+		Name: "example",
 		URL:  "8.8.8.8",
 		DNS: &DNS{
 			QueryType: "A",
@@ -260,6 +292,7 @@ func TestIntegrationEvaluateHealthForDNS(t *testing.T) {
 		},
 		Conditions: []*Condition{&conditionSuccess, &conditionBody},
 	}
+	service.ValidateAndSetDefaults()
 	result := service.EvaluateHealth()
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Conditions '%s' and %s should have been a success", conditionSuccess, conditionBody)
@@ -275,10 +308,11 @@ func TestIntegrationEvaluateHealthForDNS(t *testing.T) {
 func TestIntegrationEvaluateHealthForICMP(t *testing.T) {
 	conditionSuccess := Condition("[CONNECTED] == true")
 	service := Service{
-		Name:       "ICMP test",
+		Name:       "icmp-test",
 		URL:        "icmp://127.0.0.1",
 		Conditions: []*Condition{&conditionSuccess},
 	}
+	service.ValidateAndSetDefaults()
 	result := service.EvaluateHealth()
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Conditions '%s' should have been a success", conditionSuccess)
@@ -294,7 +328,7 @@ func TestIntegrationEvaluateHealthForICMP(t *testing.T) {
 func TestService_getIP(t *testing.T) {
 	conditionSuccess := Condition("[CONNECTED] == true")
 	service := Service{
-		Name:       "Invalid URL test",
+		Name:       "invalid-url-test",
 		URL:        "",
 		Conditions: []*Condition{&conditionSuccess},
 	}
@@ -304,3 +338,27 @@ func TestService_getIP(t *testing.T) {
 		t.Error("service.getIP(result) should've thrown an error because the URL is invalid, thus cannot be parsed")
 	}
 }
+
+func TestService_NeedsToReadBody(t *testing.T) {
+	statusCondition := Condition("[STATUS] == 200")
+	bodyCondition := Condition("[BODY].status == UP")
+	bodyConditionWithLength := Condition("len([BODY].tags) > 0")
+	if (&Service{Conditions: []*Condition{&statusCondition}}).needsToReadBody() {
+		t.Error("expected false, got true")
+	}
+	if !(&Service{Conditions: []*Condition{&bodyCondition}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+	if !(&Service{Conditions: []*Condition{&bodyConditionWithLength}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+	if !(&Service{Conditions: []*Condition{&statusCondition, &bodyCondition}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+	if !(&Service{Conditions: []*Condition{&bodyCondition, &statusCondition}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+	if !(&Service{Conditions: []*Condition{&bodyConditionWithLength, &statusCondition}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+}

core/ui/ui.go

@@ -0,0 +1,17 @@
+package ui
+
+// Config is the UI configuration for services
+type Config struct {
+	// HideHostname whether to hide the hostname in the Result
+	HideHostname bool `yaml:"hide-hostname"`
+	// DontResolveFailedConditions whether to resolve failed conditions in the Result for display in the UI
+	DontResolveFailedConditions bool `yaml:"dont-resolve-failed-conditions"`
+}
+
+// GetDefaultConfig retrieves the default UI configuration
+func GetDefaultConfig() *Config {
+	return &Config{
+		HideHostname:                false,
+		DontResolveFailedConditions: false,
+	}
+}

core/uptime.go

@@ -1,114 +1,24 @@
 package core
 
-import (
-	"log"
-	"time"
-)
-
-const (
-	// RFC3339WithoutMinutesAndSeconds is the format defined by RFC3339 (see time.RFC3339) but with the minutes
-	// and seconds hardcoded to 0.
-	RFC3339WithoutMinutesAndSeconds = "2006-01-02T15:00:00Z07:00"
-
-	numberOfHoursInTenDays = 10 * 24
-	sevenDays              = 7 * 24 * time.Hour
-)
-
 // Uptime is the struct that contains the relevant data for calculating the uptime as well as the uptime itself
+// and some other statistics
 type Uptime struct {
-	// LastSevenDays is the uptime percentage over the past 7 days
-	LastSevenDays float64 `json:"7d"`
+	// HourlyStatistics is a map containing metrics collected (value) for every hourly unix timestamps (key)
+	//
+	// Used only if the storage type is memory
+	HourlyStatistics map[int64]*HourlyUptimeStatistics `json:"-"`
+}
 
-	// LastTwentyFourHours is the uptime percentage over the past 24 hours
-	LastTwentyFourHours float64 `json:"24h"`
-
-	// LastHour is the uptime percentage over the past hour
-	LastHour float64 `json:"1h"`
-
-	successCountPerHour map[string]uint64
-	totalCountPerHour   map[string]uint64
+// HourlyUptimeStatistics is a struct containing all metrics collected over the course of an hour
+type HourlyUptimeStatistics struct {
+	TotalExecutions             uint64 // Total number of checks
+	SuccessfulExecutions        uint64 // Number of successful executions
+	TotalExecutionsResponseTime uint64 // Total response time for all executions in milliseconds
 }
 
 // NewUptime creates a new Uptime
 func NewUptime() *Uptime {
 	return &Uptime{
-		successCountPerHour: make(map[string]uint64),
-		totalCountPerHour:   make(map[string]uint64),
-	}
-}
-
-// ProcessResult processes the result by extracting the relevant from the result and recalculating the uptime
-// if necessary
-func (uptime *Uptime) ProcessResult(result *Result) {
-	timestampDateWithHour := result.Timestamp.Format(RFC3339WithoutMinutesAndSeconds)
-	if result.Success {
-		uptime.successCountPerHour[timestampDateWithHour]++
-	}
-	uptime.totalCountPerHour[timestampDateWithHour]++
-	// Clean up only when we're starting to have too many useless keys
-	// Note that this is only triggered when there are more entries than there should be after
-	// 10 days, despite the fact that we are deleting everything that's older than 7 days.
-	// This is to prevent re-iterating on every `ProcessResult` as soon as the uptime has been logged for 7 days.
-	if len(uptime.totalCountPerHour) > numberOfHoursInTenDays {
-		sevenDaysAgo := time.Now().Add(-(sevenDays + time.Hour))
-		for k := range uptime.totalCountPerHour {
-			dateWithHour, err := time.Parse(time.RFC3339, k)
-			if err != nil {
-				// This shouldn't happen, but we'll log it in case it does happen
-				log.Println("[uptime][ProcessResult] Failed to parse programmatically generated timestamp:", err.Error())
-				continue
-			}
-			if sevenDaysAgo.Unix() > dateWithHour.Unix() {
-				delete(uptime.totalCountPerHour, k)
-				delete(uptime.successCountPerHour, k)
-			}
-		}
-	}
-	if result.Success {
-		// Recalculate uptime if at least one of the 1h, 24h or 7d uptime are not 100%
-		// If they're all 100%, then recalculating the uptime would be useless unless
-		// the result added was a failure (!result.Success)
-		if uptime.LastSevenDays != 1 || uptime.LastTwentyFourHours != 1 || uptime.LastHour != 1 {
-			uptime.recalculate()
-		}
-	} else {
-		// Recalculate uptime if at least one of the 1h, 24h or 7d uptime are not 0%
-		// If they're all 0%, then recalculating the uptime would be useless unless
-		// the result added was a success (result.Success)
-		if uptime.LastSevenDays != 0 || uptime.LastTwentyFourHours != 0 || uptime.LastHour != 0 {
-			uptime.recalculate()
-		}
-	}
-}
-
-func (uptime *Uptime) recalculate() {
-	uptimeBrackets := make(map[string]uint64)
-	now := time.Now()
-	// The oldest uptime bracket starts 7 days ago, so we'll start from there
-	timestamp := now.Add(-sevenDays)
-	for now.Sub(timestamp) >= 0 {
-		timestampDateWithHour := timestamp.Format(RFC3339WithoutMinutesAndSeconds)
-		successCountForTimestamp := uptime.successCountPerHour[timestampDateWithHour]
-		totalCountForTimestamp := uptime.totalCountPerHour[timestampDateWithHour]
-		uptimeBrackets["7d_success"] += successCountForTimestamp
-		uptimeBrackets["7d_total"] += totalCountForTimestamp
-		if now.Sub(timestamp) <= 24*time.Hour {
-			uptimeBrackets["24h_success"] += successCountForTimestamp
-			uptimeBrackets["24h_total"] += totalCountForTimestamp
-		}
-		if now.Sub(timestamp) <= time.Hour {
-			uptimeBrackets["1h_success"] += successCountForTimestamp
-			uptimeBrackets["1h_total"] += totalCountForTimestamp
-		}
-		timestamp = timestamp.Add(time.Hour)
-	}
-	if uptimeBrackets["7d_total"] > 0 {
-		uptime.LastSevenDays = float64(uptimeBrackets["7d_success"]) / float64(uptimeBrackets["7d_total"])
-	}
-	if uptimeBrackets["24h_total"] > 0 {
-		uptime.LastTwentyFourHours = float64(uptimeBrackets["24h_success"]) / float64(uptimeBrackets["24h_total"])
-	}
-	if uptimeBrackets["1h_total"] > 0 {
-		uptime.LastHour = float64(uptimeBrackets["1h_success"]) / float64(uptimeBrackets["1h_total"])
+		HourlyStatistics: make(map[int64]*HourlyUptimeStatistics),
 	}
 }

core/uptime_test.go

@@ -1,79 +0,0 @@
-package core
-
-import (
-	"testing"
-	"time"
-)
-
-func TestUptime_ProcessResult(t *testing.T) {
-	service := &Service{Name: "name", Group: "group"}
-	serviceStatus := NewServiceStatus(service)
-	uptime := serviceStatus.Uptime
-
-	checkUptimes(t, serviceStatus, 0.00, 0.00, 0.00)
-
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-7 * 24 * time.Hour), Success: true})
-	checkUptimes(t, serviceStatus, 1.00, 0.00, 0.00)
-
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-6 * 24 * time.Hour), Success: false})
-	checkUptimes(t, serviceStatus, 0.50, 0.00, 0.00)
-
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-8 * 24 * time.Hour), Success: true})
-	checkUptimes(t, serviceStatus, 0.50, 0.00, 0.00)
-
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-24 * time.Hour), Success: true})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-12 * time.Hour), Success: true})
-	checkUptimes(t, serviceStatus, 0.75, 1.00, 0.00)
-
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-1 * time.Hour), Success: true})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-30 * time.Minute), Success: false})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-15 * time.Minute), Success: false})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-10 * time.Minute), Success: false})
-	checkUptimes(t, serviceStatus, 0.50, 0.50, 0.25)
-
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-120 * time.Hour), Success: true})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-119 * time.Hour), Success: true})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-118 * time.Hour), Success: true})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-117 * time.Hour), Success: true})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-10 * time.Hour), Success: true})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-8 * time.Hour), Success: true})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-30 * time.Minute), Success: true})
-	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-25 * time.Minute), Success: true})
-	checkUptimes(t, serviceStatus, 0.75, 0.70, 0.50)
-}
-
-func TestServiceStatus_AddResultUptimeIsCleaningUpAfterItself(t *testing.T) {
-	service := &Service{Name: "name", Group: "group"}
-	serviceStatus := NewServiceStatus(service)
-	now := time.Now()
-	now = time.Date(now.Year(), now.Month(), now.Day(), now.Hour(), 0, 0, 0, now.Location())
-	// Start 12 days ago
-	timestamp := now.Add(-12 * 24 * time.Hour)
-	for timestamp.Unix() <= now.Unix() {
-		serviceStatus.AddResult(&Result{Timestamp: timestamp, Success: true})
-		if len(serviceStatus.Uptime.successCountPerHour) > numberOfHoursInTenDays {
-			t.Errorf("At no point in time should there be more than %d entries in serviceStatus.successCountPerHour", numberOfHoursInTenDays)
-		}
-		//fmt.Printf("timestamp=%s; uptimeDuringLastHour=%f; timeAgo=%s\n", timestamp.Format(time.RFC3339), serviceStatus.UptimeDuringLastHour, time.Since(timestamp))
-		if now.Sub(timestamp) > time.Hour && serviceStatus.Uptime.LastHour != 0 {
-			t.Error("most recent timestamp > 1h ago, expected serviceStatus.Uptime.LastHour to be 0, got", serviceStatus.Uptime.LastHour)
-		}
-		if now.Sub(timestamp) < time.Hour && serviceStatus.Uptime.LastHour == 0 {
-			t.Error("most recent timestamp < 1h ago, expected serviceStatus.Uptime.LastHour to NOT be 0, got", serviceStatus.Uptime.LastHour)
-		}
-		// Simulate service with an interval of 1 minute
-		timestamp = timestamp.Add(3 * time.Minute)
-	}
-}
-
-func checkUptimes(t *testing.T, status *ServiceStatus, expectedUptimeDuringLastSevenDays, expectedUptimeDuringLastTwentyFourHours, expectedUptimeDuringLastHour float64) {
-	if status.Uptime.LastSevenDays != expectedUptimeDuringLastSevenDays {
-		t.Errorf("expected status.Uptime.LastSevenDays to be %f, got %f", expectedUptimeDuringLastHour, status.Uptime.LastSevenDays)
-	}
-	if status.Uptime.LastTwentyFourHours != expectedUptimeDuringLastTwentyFourHours {
-		t.Errorf("expected status.Uptime.LastTwentyFourHours to be %f, got %f", expectedUptimeDuringLastTwentyFourHours, status.Uptime.LastTwentyFourHours)
-	}
-	if status.Uptime.LastHour != expectedUptimeDuringLastHour {
-		t.Errorf("expected status.Uptime.LastHour to be %f, got %f", expectedUptimeDuringLastHour, status.Uptime.LastHour)
-	}
-}

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

@@ -1,43 +0,0 @@
-version: '3.7'
-
-services:
-  gatus:
-    container_name: gatus
-    image: twinproduction/gatus
-    restart: always
-    ports:
-      - 8080:8080
-    volumes:
-      - ./config.yaml:/config/config.yaml
-    networks:
-      - metrics
-
-  prometheus:
-    container_name: prometheus
-    image: prom/prometheus:v2.14.0
-    restart: always
-    command: --config.file=/etc/prometheus/prometheus.yml
-    ports:
-      - 9090:9090
-    volumes:
-      - ./prometheus/prometheus.yml:/etc/prometheus/prometheus.yml
-    networks:
-      - metrics
-
-  grafana:
-    container_name: grafana
-    image: grafana/grafana:6.4.4
-    restart: always
-    environment:
-      GF_SECURITY_ADMIN_PASSWORD: secret
-    ports:
-      - 3000:3000
-    volumes:
-      - ./grafana/grafana.ini/:/etc/grafana/grafana.ini:ro
-      - ./grafana/provisioning/:/etc/grafana/provisioning/:ro
-    networks:
-      - metrics
-
-networks:
-  metrics:
-    driver: bridge

example/docker-compose-mattermost/docker-compose.yml

@@ -1,24 +0,0 @@
-version: "3.8"
-
-services:
-  gatus:
-    container_name: gatus
-    image: twinproduction/gatus:latest
-    ports:
-      - 8080:8080
-    volumes:
-      - ./config.yaml:/config/config.yaml
-    networks:
-      - default
-
-  mattermost:
-    container_name: mattermost
-    image: mattermost/mattermost-preview:5.26.0
-    ports:
-      - 8065:8065
-    networks:
-      - default
-
-networks:
-  default:
-    driver: bridge

example/docker-compose/docker-compose.yml

@@ -1,8 +0,0 @@
-version: "3.8"
-services:
-    gatus:
-        image: twinproduction/gatus:latest
-        ports:
-          - 8080:8080
-        volumes:
-          - ./config.yaml:/config/config.yaml

example/kubernetes-with-auto-discovery/gatus.yaml

@@ -1,109 +0,0 @@
-apiVersion: v1
-data:
-  config.yaml: |
-    kubernetes:
-      cluster-mode: "in"
-      auto-discover: true
-      excluded-service-suffixes:
-        - canary
-      service-template:
-        interval: 30s
-        conditions:
-          - "[STATUS] == 200"
-      namespaces:
-        - name: default
-          hostname-suffix: ".default.svc.cluster.local"
-          target-path: "/health"
-          excluded-services:
-            - gatus
-kind: ConfigMap
-metadata:
-  name: gatus
-  namespace: kube-system
----
-apiVersion: rbac.authorization.k8s.io/v1
-kind: ClusterRole
-metadata:
-  name: gatus
-rules:
-  - apiGroups:
-      - ""
-    resources:
-      - services
-    verbs:
-      - list
-      - get
----
-apiVersion: v1
-automountServiceAccountToken: true
-kind: ServiceAccount
-metadata:
-  name: gatus
-  namespace: kube-system
----
-apiVersion: rbac.authorization.k8s.io/v1
-kind: ClusterRoleBinding
-metadata:
-  name: gatus
-roleRef:
-  apiGroup: rbac.authorization.k8s.io
-  kind: ClusterRole
-  name: gatus
-subjects:
-  - kind: ServiceAccount
-    name: gatus
-    namespace: kube-system
----
-apiVersion: apps/v1
-kind: Deployment
-metadata:
-  name: gatus
-  namespace: kube-system
-spec:
-  replicas: 1
-  selector:
-    matchLabels:
-      k8s-app: gatus
-  template:
-    metadata:
-      labels:
-        k8s-app: gatus
-      name: gatus
-      namespace: kube-system
-    spec:
-      containers:
-        - image: twinproduction/gatus
-          imagePullPolicy: IfNotPresent
-          name: gatus
-          ports:
-            - containerPort: 8080
-              name: http
-              protocol: TCP
-          resources:
-            limits:
-              cpu: 200m
-              memory: 50M
-            requests:
-              cpu: 50m
-              memory: 20M
-          volumeMounts:
-            - mountPath: /config
-              name: gatus-config
-      volumes:
-        - configMap:
-            name: gatus
-          name: gatus-config
----
-apiVersion: v1
-kind: Service
-metadata:
-  name: gatus
-  namespace: kube-system
-spec:
-  ports:
-    - name: http
-      port: 8080
-      protocol: TCP
-      targetPort: 8080
-  selector:
-    k8s-app: gatus

example/kubernetes/gatus.yaml

@@ -1,87 +0,0 @@
-apiVersion: v1
-data:
-  config.yaml: |
-    metrics: true
-    services:
-      - name: TwiNNatioN
-        url: https://twinnation.org/health
-        interval: 1m
-        conditions:
-          - "[STATUS] == 200"
-      - 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
-        conditions:
-          - "[STATUS] == 200"
-          - "[BODY].deleted == false"
-          - "len([BODY].text) > 0"
-          - "[BODY].text == pat(*cat*)"
-          - "[STATUS] == pat(2*)"
-          - "[CONNECTED] == true"
-      - name: Example
-        url: https://example.com/
-        conditions:
-          - "[STATUS] == 200"
-kind: ConfigMap
-metadata:
-  name: gatus
-  namespace: kube-system
----
-apiVersion: apps/v1
-kind: Deployment
-metadata:
-  name: gatus
-  namespace: kube-system
-spec:
-  replicas: 1
-  selector:
-    matchLabels:
-      k8s-app: gatus
-  template:
-    metadata:
-      labels:
-        k8s-app: gatus
-      name: gatus
-      namespace: kube-system
-    spec:
-      containers:
-        - image: twinproduction/gatus
-          imagePullPolicy: IfNotPresent
-          name: gatus
-          ports:
-            - containerPort: 8080
-              name: http
-              protocol: TCP
-          resources:
-            limits:
-              cpu: 200m
-              memory: 50M
-            requests:
-              cpu: 50m
-              memory: 20M
-          volumeMounts:
-            - mountPath: /config
-              name: gatus-config
-      volumes:
-        - configMap:
-            name: gatus
-          name: gatus-config
----
-apiVersion: v1
-kind: Service
-metadata:
-  name: gatus
-  namespace: kube-system
-spec:
-  ports:
-    - name: http
-      port: 8080
-      protocol: TCP
-      targetPort: 8080
-  selector:
-    k8s-app: gatus