service-a.go

package main

import (
	"fmt"
	"github.com/arriqaaq/boomerang"
	lucio "github.com/arriqaaq/server"
	"github.com/prometheus/client_golang/prometheus/promhttp"
	"log"
	"net/http"
	"os"
	"strings"
	"time"
)

const (
	URL_SERVICE_B = "http://0.0.0.0:8081/pong"
)

var (
	clientCnf = &boomerang.ClientConfig{
		RecordMetrics:   true,
		MetricNamespace: "service_a",
		Transport:       boomerang.DefaultTransport(),
		Backoff:         boomerang.NewConstantBackoff(100 * time.Millisecond),
		MaxRetries:      1,
	}
)

func main() {
	client := boomerang.NewHttpClient(clientCnf)

	mux := http.NewServeMux()
	mux.HandleFunc("/ping", func(w http.ResponseWriter, req *http.Request) {
		request, _ := http.NewRequest("GET", URL_SERVICE_B, strings.NewReader("gopher"))
		resp, httpErr := client.Do(request)
		if httpErr != nil {
			fmt.Println("ping failed ", httpErr)
			w.Write([]byte("fail"))
			return
		}
		defer resp.Body.Close()
		w.Write([]byte("pong"))
		return
	})
	mux.Handle("/metrics", promhttp.Handler())
	server := lucio.NewServer(mux, "0.0.0.0", 8089)
	err := server.Serve()
	log.Println("terminated", os.Getpid(), err)
}