alert-manager-receiver-example

main.go

package main

import (
	"encoding/json"
	"flag"
	"io"
	"log"
	"net/http"

	"github.com/k0kubun/pp/v3"
	"github.com/prometheus/alertmanager/notify/webhook"
)

func main() {
	addr := flag.String("addr", ":8080", "address to listen for webhook")
	flag.Parse()

	http.HandleFunc("/healthz", healthzHandler)
	http.HandleFunc("/alerts", alertsHandler)
	log.Fatal(http.ListenAndServe(*addr, nil))
}

func healthzHandler(w http.ResponseWriter, r *http.Request) {
	io.WriteString(w, "ok\n")
}

func alertsHandler(w http.ResponseWriter, r *http.Request) {
	switch r.Method {
	case http.MethodPost:
		postHandler(w, r)
	default:
		http.Error(w, "unsupported HTTP method", 400)
	}
}

func postHandler(w http.ResponseWriter, r *http.Request) {

	dec := json.NewDecoder(r.Body)
	defer r.Body.Close()

	var m webhook.Message
	if err := dec.Decode(&m); err != nil {
		log.Printf("error decoding message: %v", err)
		http.Error(w, "invalid request body", 400)
		return
	}

	pp.Println(m)

	w.WriteHeader(http.StatusOK)
}