Support custom alert provider

core/alert.go

@@ -18,5 +18,6 @@ type Alert struct {
 type AlertType string
 
 const (
-	SlackAlert AlertType = "slack"
+	SlackAlert  AlertType = "slack"
+	CustomAlert AlertType = "custom"
 )

core/alerting.go

@@ -1,5 +1,56 @@
 package core
 
-type Alerting struct {
-	Slack string `yaml:"slack"`
+import (
+	"bytes"
+	"fmt"
+	"github.com/TwinProduction/gatus/client"
+	"net/http"
+	"strings"
+)
+
+type AlertingConfig struct {
+	Slack  string               `yaml:"slack"`
+	Custom *CustomAlertProvider `yaml:"custom"`
+}
+
+type CustomAlertProvider struct {
+	Url     string            `yaml:"url"`
+	Method  string            `yaml:"method,omitempty"`
+	Body    string            `yaml:"body,omitempty"`
+	Headers map[string]string `yaml:"headers,omitempty"`
+}
+
+func (provider *CustomAlertProvider) buildRequest(serviceName, alertDescription string) *http.Request {
+	body := provider.Body
+	url := provider.Url
+	if strings.Contains(provider.Body, "[ALERT_DESCRIPTION]") {
+		body = strings.ReplaceAll(provider.Body, "[ALERT_DESCRIPTION]", alertDescription)
+	}
+	if strings.Contains(provider.Body, "[SERVICE_NAME]") {
+		body = strings.ReplaceAll(provider.Body, "[SERVICE_NAME]", serviceName)
+	}
+	if strings.Contains(provider.Url, "[ALERT_DESCRIPTION]") {
+		url = strings.ReplaceAll(provider.Url, "[ALERT_DESCRIPTION]", alertDescription)
+	}
+	if strings.Contains(provider.Url, "[SERVICE_NAME]") {
+		url = strings.ReplaceAll(provider.Url, "[SERVICE_NAME]", serviceName)
+	}
+	bodyBuffer := bytes.NewBuffer([]byte(body))
+	request, _ := http.NewRequest(provider.Method, url, bodyBuffer)
+	for k, v := range provider.Headers {
+		request.Header.Set(k, v)
+	}
+	return request
+}
+
+func (provider *CustomAlertProvider) Send(serviceName, alertDescription string) error {
+	request := provider.buildRequest(serviceName, alertDescription)
+	response, err := client.GetHttpClient().Do(request)
+	if err != nil {
+		return err
+	}
+	if response.StatusCode > 399 {
+		return fmt.Errorf("call to provider alert returned status code %d", response.StatusCode)
+	}
+	return nil
 }