// Run starts all manager sub-systems and the gRPC server at the configured
// address.
// The call never returns unless an error occurs or `Stop()` is called.
//
// TODO(aluzzardi): /!\ This function is *way* too complex. /!\
// It needs to be split into smaller manageable functions.
func (m *Manager) Run(parent context.Context) error {
	ctx, ctxCancel := context.WithCancel(parent)
	defer ctxCancel()

	// Harakiri.
	go func() {
		select {
		case <-ctx.Done():
		case <-m.stopped:
			ctxCancel()
		}
	}()

	leadershipCh, cancel := m.RaftNode.SubscribeLeadership()
	defer cancel()

	go func() {
		for leadershipEvent := range leadershipCh {
			// read out and discard all of the messages when we've stopped
			// don't acquire the mutex yet. if stopped is closed, we don't need
			// this stops this loop from starving Run()'s attempt to Lock
			select {
			case <-m.stopped:
				continue
			default:
				// do nothing, we're not stopped
			}
			// we're not stopping so NOW acquire the mutex
			m.mu.Lock()
			newState := leadershipEvent.(raft.LeadershipState)

			if newState == raft.IsLeader {
				s := m.RaftNode.MemoryStore()

				rootCA := m.config.SecurityConfig.RootCA()
				nodeID := m.config.SecurityConfig.ClientTLSCreds.NodeID()

				raftCfg := raft.DefaultRaftConfig()
				raftCfg.ElectionTick = uint32(m.RaftNode.Config.ElectionTick)
				raftCfg.HeartbeatTick = uint32(m.RaftNode.Config.HeartbeatTick)

				clusterID := m.config.SecurityConfig.ClientTLSCreds.Organization()

				initialCAConfig := ca.DefaultCAConfig()
				initialCAConfig.ExternalCAs = m.config.ExternalCAs

				s.Update(func(tx store.Tx) error {
					// Add a default cluster object to the
					// store. Don't check the error because
					// we expect this to fail unless this
					// is a brand new cluster.
					store.CreateCluster(tx, &api.Cluster{
						ID: clusterID,
						Spec: api.ClusterSpec{
							Annotations: api.Annotations{
								Name: store.DefaultClusterName,
							},
							Orchestration: api.OrchestrationConfig{
								TaskHistoryRetentionLimit: defaultTaskHistoryRetentionLimit,
							},
							Dispatcher: api.DispatcherConfig{
								HeartbeatPeriod: ptypes.DurationProto(dispatcher.DefaultHeartBeatPeriod),
							},
							Raft:     raftCfg,
							CAConfig: initialCAConfig,
						},
						RootCA: api.RootCA{
							CAKey:      rootCA.Key,
							CACert:     rootCA.Cert,
							CACertHash: rootCA.Digest.String(),
							JoinTokens: api.JoinTokens{
								Worker:  ca.GenerateJoinToken(rootCA),
								Manager: ca.GenerateJoinToken(rootCA),
							},
						},
					})
					// Add Node entry for ourself, if one
					// doesn't exist already.
					store.CreateNode(tx, &api.Node{
						ID: nodeID,
						Certificate: api.Certificate{
							CN:   nodeID,
							Role: api.NodeRoleManager,
							Status: api.IssuanceStatus{
								State: api.IssuanceStateIssued,
							},
						},
						Spec: api.NodeSpec{
							Role:       api.NodeRoleManager,
							Membership: api.NodeMembershipAccepted,
						},
					})
					return nil
				})
//.........这里部分代码省略.........

// becomeLeader starts the subsystems that are run on the leader.
func (m *Manager) becomeLeader(ctx context.Context) {
	s := m.RaftNode.MemoryStore()

	rootCA := m.config.SecurityConfig.RootCA()
	nodeID := m.config.SecurityConfig.ClientTLSCreds.NodeID()

	raftCfg := raft.DefaultRaftConfig()
	raftCfg.ElectionTick = uint32(m.RaftNode.Config.ElectionTick)
	raftCfg.HeartbeatTick = uint32(m.RaftNode.Config.HeartbeatTick)

	clusterID := m.config.SecurityConfig.ClientTLSCreds.Organization()

	initialCAConfig := ca.DefaultCAConfig()
	initialCAConfig.ExternalCAs = m.config.ExternalCAs

	s.Update(func(tx store.Tx) error {
		// Add a default cluster object to the
		// store. Don't check the error because
		// we expect this to fail unless this
		// is a brand new cluster.
		store.CreateCluster(tx, defaultClusterObject(clusterID, initialCAConfig, raftCfg, rootCA))
		// Add Node entry for ourself, if one
		// doesn't exist already.
		store.CreateNode(tx, managerNode(nodeID))
		return nil
	})

	// Attempt to rotate the key-encrypting-key of the root CA key-material
	err := m.rotateRootCAKEK(ctx, clusterID)
	if err != nil {
		log.G(ctx).WithError(err).Error("root key-encrypting-key rotation failed")
	}

	m.replicatedOrchestrator = orchestrator.NewReplicatedOrchestrator(s)
	m.globalOrchestrator = orchestrator.NewGlobalOrchestrator(s)
	m.taskReaper = orchestrator.NewTaskReaper(s)
	m.scheduler = scheduler.New(s)
	m.keyManager = keymanager.New(s, keymanager.DefaultConfig())

	// TODO(stevvooe): Allocate a context that can be used to
	// shutdown underlying manager processes when leadership is
	// lost.

	m.allocator, err = allocator.New(s)
	if err != nil {
		log.G(ctx).WithError(err).Error("failed to create allocator")
		// TODO(stevvooe): It doesn't seem correct here to fail
		// creating the allocator but then use it anyway.
	}

	if m.keyManager != nil {
		go func(keyManager *keymanager.KeyManager) {
			if err := keyManager.Run(ctx); err != nil {
				log.G(ctx).WithError(err).Error("keymanager failed with an error")
			}
		}(m.keyManager)
	}

	go func(d *dispatcher.Dispatcher) {
		if err := d.Run(ctx); err != nil {
			log.G(ctx).WithError(err).Error("Dispatcher exited with an error")
		}
	}(m.Dispatcher)

	go func(server *ca.Server) {
		if err := server.Run(ctx); err != nil {
			log.G(ctx).WithError(err).Error("CA signer exited with an error")
		}
	}(m.caserver)

	// Start all sub-components in separate goroutines.
	// TODO(aluzzardi): This should have some kind of error handling so that
	// any component that goes down would bring the entire manager down.
	if m.allocator != nil {
		go func(allocator *allocator.Allocator) {
			if err := allocator.Run(ctx); err != nil {
				log.G(ctx).WithError(err).Error("allocator exited with an error")
			}
		}(m.allocator)
	}

	go func(scheduler *scheduler.Scheduler) {
		if err := scheduler.Run(ctx); err != nil {
			log.G(ctx).WithError(err).Error("scheduler exited with an error")
		}
	}(m.scheduler)

	go func(taskReaper *orchestrator.TaskReaper) {
		taskReaper.Run()
	}(m.taskReaper)

	go func(orchestrator *orchestrator.ReplicatedOrchestrator) {
		if err := orchestrator.Run(ctx); err != nil {
			log.G(ctx).WithError(err).Error("replicated orchestrator exited with an error")
		}
	}(m.replicatedOrchestrator)

	go func(globalOrchestrator *orchestrator.GlobalOrchestrator) {
		if err := globalOrchestrator.Run(ctx); err != nil {
//.........这里部分代码省略.........