Merge pull request #13 from opthomas-prime/slack-handler

Adds slack-compatible handler

README.md

@@ -1,9 +1,14 @@
 # xmpp-webhook
-- Multipurpose XMPP-Webhook (Built for Prometheus/Grafana Alerts)
-- Based on https://github.com/atomatt/go-xmpp
+- Multipurpose XMPP-Webhook (Built for DevOps Alerts)
+- Based on https://github.com/mellium/xmpp
 
 ## Status
-`xmpp-webhook` ~~currently~~ only provides a hook for Grafana. ~~I will implement a `parserFunc` for Prometheus ASAP~~. Check https://github.com/opthomas-prime/xmpp-webhook/blob/master/handler.go to learn how to support more source services.
+`xmpp-webhook` currently support:
+
+- Grafana Webhook alerts
+- Slack Incoming Webhooks (Feedback appreciated)
+
+Check https://github.com/opthomas-prime/xmpp-webhook/blob/master/parser/ to learn how to support more source services.
 
 ## Usage
 - `xmpp-webhook` is configured via environment variables:
@@ -16,6 +21,7 @@
 
 ```
 curl -X POST -d @grafana-webhook-alert-example.json localhost:4321/grafana
+curl -X POST -d @slack-compatible-notification-example.json localhost:4321/slack
 ```
 - After parsing the body in the appropriate `parserFunc`, the notification is then distributed to the configured receivers.
 
@@ -27,7 +33,9 @@ curl -X POST -d @grafana-webhook-alert-example.json localhost:4321/grafana
 - Run: `docker run -e "XMPP_ID=alerts@example.org" -e "XMPP_PASS=xxx" -e "XMPP_RECEIVERS=receiver1@example.org,receiver2@example.org" -p 4321:4321 -d --name xmpp-webhook opthomasprime/xmpp-webhook:latest`
 
 ## Installation
-IMPORTANT NOTE: For the sake of simplicity, `xmpp-webhook` is not reconnecting to the XMPP server after a connection-loss. If you use the provided `xmpp-webhook.service` - Systemd will manage the reconnect by restarting the service.
+~~IMPORTANT NOTE: For the sake of simplicity, `xmpp-webhook` is not reconnecting to the XMPP server after a connection-loss. If you use the provided `xmpp-webhook.service` - Systemd will manage the reconnect by restarting the service.~~.
+
+-> https://github.com/mellium/xmpp automatically reconnects after a failure.
 
 - Download and extract the latest tarball (GitHub release page)
 - Install the binary: `install -D -m 744 xmpp-webhook /usr/local/bin/xmpp-webhook`

dev/slack-compatible-notification-example.json

@@ -0,0 +1,13 @@
+{
+  "channel": "#channel",
+  "icon_emoji": ":heart:",
+  "username": "Flux Deployer",
+  "attachments": [
+    {
+      "color": "#4286f4",
+      "title": "Applied flux changes to cluster",
+      "title_link": "https://GITURL/USERNAME/kubernetes/commit/COMMITSHA",
+      "text": "Event: Sync: 0f34755, jabber:deployment/test\nCommits:\n\n* \u003chttps://GITURL/USERNAME/kubernetes/commit/COMMITSHA\u003e: change test to test webhook\n\nResources updated:\n\n* jabber:deployment/test"
+    }
+  ]
+}

handler.go

@@ -1,12 +1,10 @@
 package main
 
 import (
-	"encoding/json"
-	"io/ioutil"
 	"net/http"
 )
 
-// interface for parser functions (grafana, prometheus, ...)
+// interface for parser functions
 type parserFunc func(*http.Request) (string, error)
 
 type messageHandler struct {
@@ -20,10 +18,13 @@ func (h *messageHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	m, err := h.parserFunc(r)
 	if err != nil {
 		w.WriteHeader(http.StatusInternalServerError)
+		_, _ = w.Write([]byte(err.Error()))
+	} else {
+		// send message to xmpp client
+		h.messages <- m
+		w.WriteHeader(http.StatusOK)
+		_, _ = w.Write([]byte("ok"))
 	}
-	// send message to xmpp client
-	h.messages <- m
-	w.WriteHeader(http.StatusNoContent)
 }
 
 // returns new handler with a given parser function
@@ -33,39 +34,3 @@ func newMessageHandler(m chan<- string, f parserFunc) *messageHandler {
 		parserFunc: f,
 	}
 }
-
-/*************
-GRAFANA PARSER
-*************/
-func grafanaParserFunc(r *http.Request) (string, error) {
-	// get alert data from request
-	body, err := ioutil.ReadAll(r.Body)
-	if err != nil {
-		return "", err
-	}
-
-	// grafana alert struct
-	alert := &struct {
-		Title   string `json:"title"`
-		RuleURL string `json:"ruleUrl"`
-		State   string `json:"state"`
-		Message string `json:"message"`
-	}{}
-
-	// parse body into the alert struct
-	err = json.Unmarshal(body, &alert)
-	if err != nil {
-		return "", err
-	}
-
-	// contruct alert message
-	var message string
-	switch alert.State {
-	case "ok":
-		message = ":) " + alert.Title
-	default:
-		message = ":( " + alert.Title + "\n" + alert.Message + "\n" + alert.RuleURL
-	}
-
-	return message, nil
-}

main.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"crypto/tls"
 	"encoding/xml"
+	"github.com/opthomas-prime/xmpp-webhook/parser"
 	"io"
 	"log"
 	"mellium.im/sasl"
@@ -79,11 +80,11 @@ func main() {
 		log.Fatal("XMPP_ID, XMPP_PASS or XMPP_RECEIVERS not set")
 	}
 
-	address, err := jid.Parse(xi)
+	myjid, err := jid.Parse(xi)
 	panicOnErr(err)
 
 	// connect to xmpp server
-	xmppSession, err := initXMPP(address, xp, skipTLSVerify, useXMPPS)
+	xmppSession, err := initXMPP(myjid, xp, skipTLSVerify, useXMPPS)
 	panicOnErr(err)
 	defer closeXMPP(xmppSession)
 
@@ -115,6 +116,7 @@ func main() {
 			reply := MessageBody{
 				Message: stanza.Message{
 					To:   msg.From.Bare(),
+					From: myjid,
 					Type: stanza.ChatMessage,
 				},
 				Body: msg.Body,
@@ -140,6 +142,7 @@ func main() {
 				_ = xmppSession.Encode(MessageBody{
 					Message: stanza.Message{
 						To:   recipient,
+						From: myjid,
 						Type: stanza.ChatMessage,
 					},
 					Body: m,
@@ -148,8 +151,9 @@ func main() {
 		}
 	}()
 
-	// initialize handler for grafana alerts
-	http.Handle("/grafana", newMessageHandler(messages, grafanaParserFunc))
+	// initialize handlers with accociated parser functions
+	http.Handle("/grafana", newMessageHandler(messages, parser.GrafanaParserFunc))
+	http.Handle("/slack", newMessageHandler(messages, parser.SlackParserFunc))
 
 	// listen for requests
 	_ = http.ListenAndServe(":4321", nil)

parser/common.go

@@ -0,0 +1,4 @@
+package parser
+
+const readErr string = "failed to read alert body"
+const parseErr string = "failed to parse alert body"

parser/grafana.go

@@ -0,0 +1,42 @@
+package parser
+
+import (
+	"encoding/json"
+	"errors"
+	"io/ioutil"
+	"net/http"
+)
+
+func GrafanaParserFunc(r *http.Request) (string, error) {
+	// get alert data from request
+	body, err := ioutil.ReadAll(r.Body)
+	if err != nil {
+		return "", errors.New(readErr)
+	}
+
+	alert := &struct {
+		Title   string `json:"title"`
+		RuleURL string `json:"ruleUrl"`
+		State   string `json:"state"`
+		Message string `json:"message"`
+	}{}
+
+	// parse body into the alert struct
+	err = json.Unmarshal(body, &alert)
+	if err != nil {
+		return "", errors.New(parseErr)
+	}
+
+	// contruct alert message
+	var message string
+	switch alert.State {
+	case "ok":
+		message = ":) " + alert.Title
+	default:
+		message = ":( " + alert.Title + "\n\n"
+		message += alert.Message + "\n\n"
+		message += alert.RuleURL
+	}
+
+	return message, nil
+}

parser/slack-compatible.go

@@ -0,0 +1,44 @@
+package parser
+
+import (
+	"encoding/json"
+	"errors"
+	"io/ioutil"
+	"net/http"
+)
+
+func SlackParserFunc(r *http.Request) (string, error) {
+	// get alert data from request
+	body, err := ioutil.ReadAll(r.Body)
+	if err != nil {
+		return "", errors.New(readErr)
+	}
+
+	alert := struct {
+		Text        string `json:"text"`
+		Attachments []struct {
+			Title     string `json:"title"`
+			TitleLink string `json:"title_link"`
+			Text      string `json:"text"`
+		} `json:"attachments"`
+	}{}
+
+	// parse body into the alert struct
+	err = json.Unmarshal(body, &alert)
+	if err != nil {
+		return "", errors.New(parseErr)
+	}
+
+	// contruct alert message
+	message := alert.Text
+	for _, attachment := range alert.Attachments {
+		if len(message) > 0 {
+			message = message + "\n"
+		}
+		message += attachment.Title + "\n"
+		message += attachment.TitleLink + "\n\n"
+		message += attachment.Text
+	}
+
+	return message, nil
+}