Example #1
0
func setupReplication(c *cli.Context, cluster cluster.Cluster, server *api.Server, discovery discovery.Backend, addr string, leaderTTL time.Duration, tlsConfig *tls.Config) {
	kvDiscovery, ok := discovery.(*kvdiscovery.Discovery)
	if !ok {
		log.Fatal("Leader election is only supported with consul, etcd and zookeeper discovery.")
	}
	client := kvDiscovery.Store()
	p := path.Join(kvDiscovery.Prefix(), leaderElectionPath)

	candidate := leadership.NewCandidate(client, p, addr, leaderTTL)
	follower := leadership.NewFollower(client, p)

	primary := api.NewPrimary(cluster, tlsConfig, &statusHandler{cluster, candidate, follower}, c.GlobalBool("debug"), c.Bool("cors"))
	replica := api.NewReplica(primary, tlsConfig)

	go func() {
		for {
			run(candidate, server, primary, replica)
			time.Sleep(defaultRecoverTime)
		}
	}()

	go func() {
		for {
			follow(follower, replica, addr)
			time.Sleep(defaultRecoverTime)
		}
	}()

	server.SetHandler(primary)
}
Example #2
0
func run(candidate *leadership.Candidate, server *api.Server, primary *mux.Router, replica *api.Replica) {
	electedCh, errCh := candidate.RunForElection()
	for {
		select {
		case isElected := <-electedCh:
			if isElected {
				log.Info("Leader Election: Cluster leadership acquired")
				server.SetHandler(primary)
			} else {
				log.Info("Leader Election: Cluster leadership lost")
				server.SetHandler(replica)
			}

		case err := <-errCh:
			log.Error(err)
			return
		}
	}
}
Example #3
0
func run(cl cluster.Cluster, candidate *leadership.Candidate, server *api.Server, primary *mux.Router, replica *api.Replica) {
	electedCh, errCh := candidate.RunForElection()
	var watchdog *cluster.Watchdog
	for {
		select {
		case isElected := <-electedCh:
			if isElected {
				log.Info("Leader Election: Cluster leadership acquired")
				watchdog = cluster.NewWatchdog(cl)
				server.SetHandler(primary)
			} else {
				log.Info("Leader Election: Cluster leadership lost")
				cl.UnregisterEventHandler(watchdog)
				server.SetHandler(replica)
			}

		case err := <-errCh:
			log.Error(err)
			return
		}
	}
}
Example #4
0
func setupLeaderElection(server *api.Server, apiHandler http.Handler, discovery discovery.Discovery, addr string, tlsConfig *tls.Config) {
	kvDiscovery, ok := discovery.(*kvdiscovery.Discovery)
	if !ok {
		log.Fatal("Leader election is only supported with consul, etcd and zookeeper discovery.")
	}
	client := kvDiscovery.Store()

	candidate := leadership.NewCandidate(client, leaderElectionPath, addr)
	follower := leadership.NewFollower(client, leaderElectionPath)

	proxy := api.NewReverseProxy(tlsConfig)

	go func() {
		candidate.RunForElection()
		electedCh := candidate.ElectedCh()
		for isElected := range electedCh {
			if isElected {
				log.Info("Cluster leadership acquired")
				server.SetHandler(apiHandler)
			} else {
				log.Info("Cluster leadership lost")
				server.SetHandler(proxy)
			}
		}
	}()

	go func() {
		follower.FollowElection()
		leaderCh := follower.LeaderCh()
		for leader := range leaderCh {
			log.Infof("New leader elected: %s", leader)
			if leader == addr {
				proxy.SetDestination("")
			} else {
				proxy.SetDestination(leader)
			}
		}
	}()
}
Example #5
0
func setupReplication(c *cli.Context, cluster cluster.Cluster, server *api.Server, discovery discovery.Discovery, addr string, tlsConfig *tls.Config) {
	kvDiscovery, ok := discovery.(*kvdiscovery.Discovery)
	if !ok {
		log.Fatal("Leader election is only supported with consul, etcd and zookeeper discovery.")
	}
	client := kvDiscovery.Store()
	p := path.Join(kvDiscovery.Prefix(), leaderElectionPath)

	candidate := leadership.NewCandidate(client, p, addr)
	follower := leadership.NewFollower(client, p)

	primary := api.NewPrimary(cluster, tlsConfig, &statusHandler{cluster, candidate, follower}, c.Bool("cors"))
	replica := api.NewReplica(primary, tlsConfig)

	go func() {
		candidate.RunForElection()
		electedCh := candidate.ElectedCh()
		for isElected := range electedCh {
			if isElected {
				log.Info("Cluster leadership acquired")
				server.SetHandler(primary)
			} else {
				log.Info("Cluster leadership lost")
				server.SetHandler(replica)
			}
		}
	}()

	go func() {
		follower.FollowElection()
		leaderCh := follower.LeaderCh()
		for leader := range leaderCh {
			log.Infof("New leader elected: %s", leader)
			if leader == addr {
				replica.SetPrimary("")
			} else {
				replica.SetPrimary(leader)
			}
		}
	}()

	server.SetHandler(primary)
}