add prometheus support

config_example.conf

@@ -10,6 +10,7 @@ startup_notify_muc = []
 
 # suported hooks are, which could be declared multiple times with different `secrets` (see [[hooks.grafana]]):
 [[hooks.grafana]]
+[[hooks.prometheus]]
 [[hooks.git]]
 [[hooks.gitlab]]
 [[hooks.circleci]]
@@ -19,6 +20,9 @@ secret = ""
 notify_muc = []
 notify_user = []
 
+# for handling webhooks from prometheus alertmanager
+
+[[hooks.prometheus]]
 
 # for handling webhooks from grafana
 # at http://localhost:8080/grafana

main.go

@@ -15,6 +15,7 @@ import (
 	_ "dev.sum7.eu/genofire/hook2xmpp/git"
 	_ "dev.sum7.eu/genofire/hook2xmpp/gitlab"
 	_ "dev.sum7.eu/genofire/hook2xmpp/grafana"
+	_ "dev.sum7.eu/genofire/hook2xmpp/prometheus"
 	"dev.sum7.eu/genofire/hook2xmpp/runtime"
 )
 

prometheus/main.go

@@ -0,0 +1,63 @@
+package prometheus
+
+import (
+	"fmt"
+	"strings"
+
+	"net/http"
+
+	libHTTP "dev.sum7.eu/genofire/golang-lib/http"
+	"github.com/bdlm/log"
+	xmpp "github.com/mattn/go-xmpp"
+	"github.com/prometheus/alertmanager/notify"
+
+	"dev.sum7.eu/genofire/hook2xmpp/runtime"
+)
+
+const hookType = "prometheus"
+
+func init() {
+	runtime.HookRegister[hookType] = func(client *xmpp.Client, hooks []runtime.Hook) func(w http.ResponseWriter, r *http.Request) {
+		log.WithField("type", hookType).Info("loaded")
+		return func(w http.ResponseWriter, r *http.Request) {
+			logger := log.WithField("type", hookType)
+
+			var request notify.WebhookMessage
+			if err := libHTTP.Read(r, &request); err != nil {
+				logger.Errorf("no readable payload: %s", err)
+				http.Error(w, fmt.Sprintf("no readable payload"), http.StatusInternalServerError)
+				return
+			}
+
+			content := strings.Join(request.GroupLabels.Values(), " ")
+			firingAlerts := request.Alerts.Firing()
+			if len(firingAlerts) > 0 {
+				for _, a := range firingAlerts {
+					if description, ok := a.Annotations["description"]; ok {
+						content = fmt.Sprintf("%s\n%s", content, description)
+					}
+				}
+				content = fmt.Sprintf("[%s:%d] %s", request.Status, len(firingAlerts), content)
+			} else {
+				content = fmt.Sprintf("[%s] %s", request.Status, content)
+			}
+
+			logger = logger.WithField("body", content)
+
+			ok := false
+			token := strings.TrimSpace(strings.TrimPrefix(r.Header.Get("Authorization"), "Bearer "))
+			for _, hook := range hooks {
+				if token != hook.Secret {
+					continue
+				}
+				logger.Infof("run hook")
+				runtime.Notify(client, hook, content)
+				ok = true
+			}
+			if !ok {
+				logger.Warnf("no hook found")
+				http.Error(w, fmt.Sprintf("no configuration for %s for url: %s", hookType, request.ExternalURL), http.StatusNotFound)
+			}
+		}
+	}
+}

prometheus/main_test.go

@@ -0,0 +1 @@
+package prometheus