feat(alerting): Add group-specific webhook URL for teams (#266)

* feat(alert): Add group-specific webhook URL for teams

Add group-specific webhook URL for teams alert

ref: https://github.com/TwiN/gatus/issues/96

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

* Update README.md

* Update README.md

README.md

@@ -652,16 +652,25 @@ Here's an example of what the notifications look like:
 
 
 #### Configuring Teams alerts
+
 | Parameter                                | Description                                                                                | Default       |
-|:-------------------------------|:-------------------------------------------------------------------------------------------|:--------------|
+|:---------------------------------------- |:------------------------------------------------------------------------------------------ |:------------- |
 | `alerting.teams`                         | Configuration for alerts of type `teams`                                                   | `{}`          |
 | `alerting.teams.webhook-url`             | Teams Webhook URL                                                                          | Required `""` |
 | `alerting.teams.default-alert`           | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A           |
+| `alerting.teams.overrides`               | List of overrides that may be prioritized over the default configuration                   | `[]`          |
+| `alerting.teams.overrides[].group`       | Endpoint group for which the configuration will be overridden by this configuration        | `""`          |
+| `alerting.teams.overrides[].webhook-url` | Teams Webhook URL                                                                          | `""`          |
 
 ```yaml
 alerting:
   teams:
     webhook-url: "https://********.webhook.office.com/webhookb2/************"
+    # You can also add group-specific to keys, which will 
+    # override the to key above for the specified groups
+    overrides:
+      - group: "core"
+        webhook-url: "https://********.webhook.office.com/webhookb3/************"
 
 endpoints:
   - name: website
@@ -676,6 +685,19 @@ endpoints:
         enabled: true
         description: "healthcheck failed"
         send-on-resolved: true
+
+  - name: back-end
+    group: core
+    url: "https://example.org/"
+    interval: 5m
+    conditions:
+      - "[STATUS] == 200"
+      - "[CERTIFICATE_EXPIRATION] > 48h"
+    alerts:
+      - type: teams
+        enabled: true
+        description: "healthcheck failed"
+        send-on-resolved: true
 ```
 
 Here's an example of what the notifications look like:

alerting/provider/teams/teams.go

@@ -17,17 +17,35 @@ type AlertProvider struct {
 
 	// DefaultAlert is the default alert configuration to use for endpoints with an alert of the appropriate type
 	DefaultAlert *alert.Alert `yaml:"default-alert,omitempty"`
+
+	// Overrides is a list of Override that may be prioritized over the default configuration
+	Overrides []Override `yaml:"overrides,omitempty"`
+}
+
+// Override is a case under which the default integration is overridden
+type Override struct {
+	Group      string `yaml:"group"`
+	WebhookURL string `yaml:"webhook-url"`
 }
 
 // IsValid returns whether the provider's configuration is valid
 func (provider *AlertProvider) IsValid() bool {
+	registeredGroups := make(map[string]bool)
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if isAlreadyRegistered := registeredGroups[override.Group]; isAlreadyRegistered || override.Group == "" || len(override.WebhookURL) == 0 {
+				return false
+			}
+			registeredGroups[override.Group] = true
+		}
+	}
 	return len(provider.WebhookURL) > 0
 }
 
 // Send an alert using the provider
 func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert, result *core.Result, resolved bool) error {
 	buffer := bytes.NewBuffer([]byte(provider.buildRequestBody(endpoint, alert, result, resolved)))
-	request, err := http.NewRequest(http.MethodPost, provider.WebhookURL, buffer)
+	request, err := http.NewRequest(http.MethodPost, provider.getWebhookURLForGroup(endpoint.Group), buffer)
 	if err != nil {
 		return err
 	}
@@ -86,6 +104,18 @@ func (provider *AlertProvider) buildRequestBody(endpoint *core.Endpoint, alert *
 }`, color, message, description, endpoint.URL, results)
 }
 
+// getWebhookURLForGroup returns the appropriate Webhook URL integration to for a given group
+func (provider *AlertProvider) getWebhookURLForGroup(group string) string {
+	if provider.Overrides != nil {
+		for _, override := range provider.Overrides {
+			if group == override.Group {
+				return override.WebhookURL
+			}
+		}
+	}
+	return provider.WebhookURL
+}
+
 // GetDefaultAlert returns the provider's default alert configuration
 func (provider AlertProvider) GetDefaultAlert() *alert.Alert {
 	return provider.DefaultAlert

alerting/provider/teams/teams_test.go

@@ -11,7 +11,7 @@ import (
 	"github.com/TwiN/gatus/v3/test"
 )
 
-func TestAlertProvider_IsValid(t *testing.T) {
+func TestAlertDefaultProvider_IsValid(t *testing.T) {
 	invalidProvider := AlertProvider{WebhookURL: ""}
 	if invalidProvider.IsValid() {
 		t.Error("provider shouldn't have been valid")
@@ -22,6 +22,43 @@ func TestAlertProvider_IsValid(t *testing.T) {
 	}
 }
 
+func TestAlertProvider_IsValidWithOverride(t *testing.T) {
+	providerWithInvalidOverrideGroup := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "",
+			},
+		},
+	}
+	if providerWithInvalidOverrideGroup.IsValid() {
+		t.Error("provider Group shouldn't have been valid")
+	}
+	providerWithInvalidOverrideTo := AlertProvider{
+		Overrides: []Override{
+			{
+				WebhookURL: "",
+				Group:      "group",
+			},
+		},
+	}
+	if providerWithInvalidOverrideTo.IsValid() {
+		t.Error("provider integration key shouldn't have been valid")
+	}
+	providerWithValidOverride := AlertProvider{
+		WebhookURL: "http://example.com",
+		Overrides: []Override{
+			{
+				WebhookURL: "http://example.com",
+				Group:      "group",
+			},
+		},
+	}
+	if !providerWithValidOverride.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
 func TestAlertProvider_Send(t *testing.T) {
 	defer client.InjectHTTPClient(nil)
 	firstDescription := "description-1"
@@ -156,3 +193,66 @@ func TestAlertProvider_GetDefaultAlert(t *testing.T) {
 		t.Error("expected default alert to be nil")
 	}
 }
+
+func TestAlertProvider_getWebhookURLForGroup(t *testing.T) {
+	tests := []struct {
+		Name           string
+		Provider       AlertProvider
+		InputGroup     string
+		ExpectedOutput string
+	}{
+		{
+			Name: "provider-no-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-no-override-specify-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides:  nil,
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-no-group-should-default",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "",
+			ExpectedOutput: "http://example.com",
+		},
+		{
+			Name: "provider-with-override-specify-group-should-override",
+			Provider: AlertProvider{
+				WebhookURL: "http://example.com",
+				Overrides: []Override{
+					{
+						Group:      "group",
+						WebhookURL: "http://example01.com",
+					},
+				},
+			},
+			InputGroup:     "group",
+			ExpectedOutput: "http://example01.com",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.Name, func(t *testing.T) {
+			if got := tt.Provider.getWebhookURLForGroup(tt.InputGroup); got != tt.ExpectedOutput {
+				t.Errorf("AlertProvider.getToForGroup() = %v, want %v", got, tt.ExpectedOutput)
+			}
+		})
+	}
+}