pkar / dinghy

Dinghy implements leader election using the raft protocol

dinghy

Dinghy implements leader election using part of the raft protocol. It might be useful if you have several workers but only want one of them at a time doing things.

package main

import (
	"flag"
	"fmt"
	"log"
	"net/http"
	"os"
	"strings"

	"github.com/upsight/dinghy"
)

func main() {
	addr := flag.String("addr", "localhost:8899", "The address to listen on.")
	nodesList := flag.String("nodes", "localhost:8898,localhost:8897", "Comma separated list of host:port")
	flag.Parse()

	nodes := strings.Split(*nodesList, ",")
	nodes = append(nodes, *addr)

	onLeader := func() error {
		fmt.Println("leader")
		return nil
	}
	onFollower := func() error {
		fmt.Println("me follower")
		return nil
	}

	din, err := dinghy.New(
		*addr,
		nodes,
		onLeader,
		onFollower,
		&dinghy.LogLogger{Logger: log.New(os.Stderr, "logger: ", log.Lshortfile)},
		dinghy.DefaultElectionTickRange,
		dinghy.DefaultHeartbeatTickRange,
	)
	if err != nil {
		log.Fatal(err)
	}
	for _, route := range din.Routes() {
		http.HandleFunc(route.Path, route.Handler)
	}
	go func() {
		if err := din.Start(); err != nil {
			log.Fatal(err)
		}
	}()
	log.Fatal(http.ListenAndServe(*addr, nil))
}