Transfer alerting rule and Prometheus URL to alertmanager.

main.go

@@ -202,8 +202,8 @@ func main() {
 	}
 	go ruleManager.Run()
 
-	// Queue depth will need to be exposed
+	prometheusUrl := web.MustBuildServerUrl()
-	notificationHandler := notification.NewNotificationHandler(*alertmanagerUrl, notifications)
+	notificationHandler := notification.NewNotificationHandler(*alertmanagerUrl, prometheusUrl, notifications)
 	go notificationHandler.Run()
 
 	flags := map[string]string{}

notification/notification.go

@@ -42,6 +42,8 @@ var (
 type NotificationHandler struct {
 	// The URL of the alert manager to send notifications to.
 	alertmanagerUrl string
+	// The URL of this Prometheus instance to include in notifications.
+	prometheusUrl string
 	// Buffer of notifications that have not yet been sent.
 	pendingNotifications <-chan rules.NotificationReqs
 	// HTTP client with custom timeout settings.
@@ -49,11 +51,12 @@ type NotificationHandler struct {
 }
 
 // Construct a new NotificationHandler.
-func NewNotificationHandler(alertmanagerUrl string, notificationReqs <-chan rules.NotificationReqs) *NotificationHandler {
+func NewNotificationHandler(alertmanagerUrl string, prometheusUrl string, notificationReqs <-chan rules.NotificationReqs) *NotificationHandler {
 	return &NotificationHandler{
 		alertmanagerUrl:      alertmanagerUrl,
 		pendingNotifications: notificationReqs,
 		httpClient:           utility.NewDeadlineClient(*deadline),
+		prometheusUrl:        prometheusUrl,
 	}
 }
 
@@ -70,6 +73,8 @@ func (n *NotificationHandler) sendNotifications(reqs rules.NotificationReqs) err
 			"Payload": map[string]interface{}{
 				"Value":        req.ActiveAlert.Value,
 				"ActiveSince":  req.ActiveAlert.ActiveSince,
+				"GeneratorUrl": n.prometheusUrl,
+				"AlertingRule": req.Rule.String(),
 			},
 		})
 	}

web/web.go

@@ -18,8 +18,10 @@ import (
 	"fmt"
 	"html/template"
 	"log"
+	"net"
 	"net/http"
 	"net/http/pprof"
+	"os"
 
 	"code.google.com/p/gorest"
 
@@ -64,7 +66,7 @@ func (w WebService) ServeForever() error {
 	exp.HandleFunc("/graph", graphHandler)
 
 	exp.Handle("/api/", compressionHandler{handler: gorest.Handle()})
-	exp.Handle("/metrics.json", prometheus.DefaultHandler)
+	exp.Handle("/metrics", prometheus.DefaultHandler)
 	if *useLocalAssets {
 		exp.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.Dir("web/static"))))
 	} else {
@@ -137,3 +139,15 @@ func executeTemplate(w http.ResponseWriter, name string, data interface{}) {
 		log.Printf("Error executing template: %s", err)
 	}
 }
+
+func MustBuildServerUrl() string {
+	_, port, err := net.SplitHostPort(*listenAddress)
+	if err != nil {
+		panic(err)
+	}
+	hostname, err := os.Hostname()
+	if err != nil {
+		panic(err)
+	}
+	return fmt.Sprintf("http://%s:%s", hostname, port)
+}