Пример #1
0
func (cli *DaemonCli) reloadConfig() {
	reload := func(config *daemon.Config) {

		// Reload the authorization plugin
		cli.authzMiddleware.SetPlugins(config.AuthorizationPlugins)

		if err := cli.d.Reload(config); err != nil {
			logrus.Errorf("Error reconfiguring the daemon: %v", err)
			return
		}

		if config.IsValueSet("debug") {
			debugEnabled := utils.IsDebugEnabled()
			switch {
			case debugEnabled && !config.Debug: // disable debug
				utils.DisableDebug()
				cli.api.DisableProfiler()
			case config.Debug && !debugEnabled: // enable debug
				utils.EnableDebug()
				cli.api.EnableProfiler()
			}

		}
	}

	if err := daemon.ReloadConfiguration(*cli.configFile, cli.flags, reload); err != nil {
		logrus.Error(err)
	}
}
Пример #2
0
// Reload reads configuration changes and modifies the
// server according to those changes.
// Currently, only the --debug configuration is taken into account.
func (s *Server) Reload(config *daemon.Config) {
	debugEnabled := utils.IsDebugEnabled()
	switch {
	case debugEnabled && !config.Debug: // disable debug
		utils.DisableDebug()
		s.routerSwapper.Swap(s.createMux())
	case config.Debug && !debugEnabled: // enable debug
		utils.EnableDebug()
		s.routerSwapper.Swap(s.createMux())
	}
}
Пример #3
0
// Reload reads configuration changes and modifies the
// server according to those changes.
// Currently, only the --debug configuration is taken into account.
func (s *Server) Reload(debug bool) {
	debugEnabled := utils.IsDebugEnabled()
	switch {
	case debugEnabled && !debug: // disable debug
		utils.DisableDebug()
		s.routerSwapper.Swap(s.createMux())
	case debug && !debugEnabled: // enable debug
		utils.EnableDebug()
		s.routerSwapper.Swap(s.createMux())
	}
}
Пример #4
0
func TestClientDebugEnabled(t *testing.T) {
	defer utils.DisableDebug()

	cmd := newDockerCommand(&command.DockerCli{})
	cmd.Flags().Set("debug", "true")

	err := cmd.PersistentPreRunE(cmd, []string{})
	assert.NilError(t, err)
	assert.Equal(t, os.Getenv("DEBUG"), "1")
	assert.Equal(t, logrus.GetLevel(), logrus.DebugLevel)
}
Пример #5
0
func TestClientDebugEnabled(t *testing.T) {
	defer utils.DisableDebug()

	clientFlags.Common.FlagSet.Parse([]string{"-D"})
	clientFlags.PostParse()

	if os.Getenv("DEBUG") != "1" {
		t.Fatal("expected debug enabled, got false")
	}
	if logrus.GetLevel() != logrus.DebugLevel {
		t.Fatalf("expected logrus debug level, got %v", logrus.GetLevel())
	}
}
Пример #6
0
func TestClientDebugEnabled(t *testing.T) {
	defer utils.DisableDebug()

	cmd := newDockerCommand(&command.DockerCli{})
	cmd.Flags().Set("debug", "true")

	if err := cmd.PersistentPreRunE(cmd, []string{}); err != nil {
		t.Fatalf("Unexpected error: %s", err.Error())
	}

	if os.Getenv("DEBUG") != "1" {
		t.Fatal("expected debug enabled, got false")
	}
	if logrus.GetLevel() != logrus.DebugLevel {
		t.Fatalf("expected logrus debug level, got %v", logrus.GetLevel())
	}
}
Пример #7
0
func (cli *DaemonCli) reloadConfig() {
	reload := func(config *daemon.Config) {
		if err := cli.d.Reload(config); err != nil {
			logrus.Errorf("Error reconfiguring the daemon: %v", err)
			return
		}
		if config.IsValueSet("debug") {
			debugEnabled := utils.IsDebugEnabled()
			switch {
			case debugEnabled && !config.Debug: // disable debug
				utils.DisableDebug()
				cli.api.DisableProfiler()
			case config.Debug && !debugEnabled: // enable debug
				utils.EnableDebug()
				cli.api.EnableProfiler()
			}

		}
	}

	if err := daemon.ReloadConfiguration(*cli.configFile, flag.CommandLine, reload); err != nil {
		logrus.Error(err)
	}
}
Пример #8
0
// CmdDaemon is the daemon command, called the raw arguments after `docker daemon`.
func (cli *DaemonCli) CmdDaemon(args ...string) error {
	// warn from uuid package when running the daemon
	uuid.Loggerf = logrus.Warnf

	if !commonFlags.FlagSet.IsEmpty() || !clientFlags.FlagSet.IsEmpty() {
		// deny `docker -D daemon`
		illegalFlag := getGlobalFlag()
		fmt.Fprintf(os.Stderr, "invalid flag '-%s'.\nSee 'docker daemon --help'.\n", illegalFlag.Names[0])
		os.Exit(1)
	} else {
		// allow new form `docker daemon -D`
		flag.Merge(cli.flags, commonFlags.FlagSet)
	}

	configFile := cli.flags.String([]string{daemonConfigFileFlag}, defaultDaemonConfigFile, "Daemon configuration file")

	cli.flags.ParseFlags(args, true)
	commonFlags.PostParse()

	if commonFlags.TrustKey == "" {
		commonFlags.TrustKey = filepath.Join(getDaemonConfDir(), defaultTrustKeyFile)
	}
	cliConfig, err := loadDaemonCliConfig(cli.Config, cli.flags, commonFlags, *configFile)
	if err != nil {
		fmt.Fprint(os.Stderr, err)
		os.Exit(1)
	}
	cli.Config = cliConfig

	if cli.Config.Debug {
		utils.EnableDebug()
	}

	if utils.ExperimentalBuild() {
		logrus.Warn("Running experimental build")
	}

	logrus.SetFormatter(&logrus.TextFormatter{
		TimestampFormat: jsonlog.RFC3339NanoFixed,
		DisableColors:   cli.Config.RawLogs,
	})

	if err := setDefaultUmask(); err != nil {
		logrus.Fatalf("Failed to set umask: %v", err)
	}

	if len(cli.LogConfig.Config) > 0 {
		if err := logger.ValidateLogOpts(cli.LogConfig.Type, cli.LogConfig.Config); err != nil {
			logrus.Fatalf("Failed to set log opts: %v", err)
		}
	}

	var pfile *pidfile.PIDFile
	if cli.Pidfile != "" {
		pf, err := pidfile.New(cli.Pidfile)
		if err != nil {
			logrus.Fatalf("Error starting daemon: %v", err)
		}
		pfile = pf
		defer func() {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}()
	}

	serverConfig := &apiserver.Config{
		AuthorizationPluginNames: cli.Config.AuthorizationPlugins,
		Logging:                  true,
		SocketGroup:              cli.Config.SocketGroup,
		Version:                  dockerversion.Version,
	}
	serverConfig = setPlatformServerConfig(serverConfig, cli.Config)

	if cli.Config.TLS {
		tlsOptions := tlsconfig.Options{
			CAFile:   cli.Config.CommonTLSOptions.CAFile,
			CertFile: cli.Config.CommonTLSOptions.CertFile,
			KeyFile:  cli.Config.CommonTLSOptions.KeyFile,
		}

		if cli.Config.TLSVerify {
			// server requires and verifies client's certificate
			tlsOptions.ClientAuth = tls.RequireAndVerifyClientCert
		}
		tlsConfig, err := tlsconfig.Server(tlsOptions)
		if err != nil {
			logrus.Fatal(err)
		}
		serverConfig.TLSConfig = tlsConfig
	}

	if len(cli.Config.Hosts) == 0 {
		cli.Config.Hosts = make([]string, 1)
	}

	api := apiserver.New(serverConfig)

	for i := 0; i < len(cli.Config.Hosts); i++ {
		var err error
		if cli.Config.Hosts[i], err = opts.ParseHost(cli.Config.TLS, cli.Config.Hosts[i]); err != nil {
			logrus.Fatalf("error parsing -H %s : %v", cli.Config.Hosts[i], err)
		}

		protoAddr := cli.Config.Hosts[i]
		protoAddrParts := strings.SplitN(protoAddr, "://", 2)
		if len(protoAddrParts) != 2 {
			logrus.Fatalf("bad format %s, expected PROTO://ADDR", protoAddr)
		}
		l, err := listeners.Init(protoAddrParts[0], protoAddrParts[1], serverConfig.SocketGroup, serverConfig.TLSConfig)
		if err != nil {
			logrus.Fatal(err)
		}

		logrus.Debugf("Listener created for HTTP on %s (%s)", protoAddrParts[0], protoAddrParts[1])
		api.Accept(protoAddrParts[1], l...)
	}

	if err := migrateKey(); err != nil {
		logrus.Fatal(err)
	}
	cli.TrustKeyPath = commonFlags.TrustKey

	registryService := registry.NewService(cli.Config.ServiceOptions)
	d, err := daemon.NewDaemon(cli.Config, registryService)
	if err != nil {
		if pfile != nil {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}
		logrus.Fatalf("Error starting daemon: %v", err)
	}

	logrus.Info("Daemon has completed initialization")

	logrus.WithFields(logrus.Fields{
		"version":     dockerversion.Version,
		"commit":      dockerversion.GitCommit,
		"execdriver":  d.ExecutionDriver().Name(),
		"graphdriver": d.GraphDriverName(),
	}).Info("Docker daemon")

	initRouter(api, d)

	reload := func(config *daemon.Config) {
		if err := d.Reload(config); err != nil {
			logrus.Errorf("Error reconfiguring the daemon: %v", err)
			return
		}
		if config.IsValueSet("debug") {
			debugEnabled := utils.IsDebugEnabled()
			switch {
			case debugEnabled && !config.Debug: // disable debug
				utils.DisableDebug()
				api.DisableProfiler()
			case config.Debug && !debugEnabled: // enable debug
				utils.EnableDebug()
				api.EnableProfiler()
			}

		}
	}

	setupConfigReloadTrap(*configFile, cli.flags, reload)

	// The serve API routine never exits unless an error occurs
	// We need to start it as a goroutine and wait on it so
	// daemon doesn't exit
	serveAPIWait := make(chan error)
	go api.Wait(serveAPIWait)

	signal.Trap(func() {
		api.Close()
		<-serveAPIWait
		shutdownDaemon(d, 15)
		if pfile != nil {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}
	})

	// after the daemon is done setting up we can notify systemd api
	notifySystem()

	// Daemon is fully initialized and handling API traffic
	// Wait for serve API to complete
	errAPI := <-serveAPIWait
	shutdownDaemon(d, 15)
	if errAPI != nil {
		if pfile != nil {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}
		logrus.Fatalf("Shutting down due to ServeAPI error: %v", errAPI)
	}
	return nil
}
Пример #9
0
func (cli *DaemonCli) start() {
	// warn from uuid package when running the daemon
	uuid.Loggerf = logrus.Warnf

	flags := flag.CommandLine
	cli.commonFlags.PostParse()

	if cli.commonFlags.TrustKey == "" {
		cli.commonFlags.TrustKey = filepath.Join(getDaemonConfDir(), cliflags.DefaultTrustKeyFile)
	}
	cliConfig, err := loadDaemonCliConfig(cli.Config, flags, cli.commonFlags, *cli.configFile)
	if err != nil {
		fmt.Fprint(os.Stderr, err)
		os.Exit(1)
	}
	cli.Config = cliConfig

	if cli.Config.Debug {
		utils.EnableDebug()
	}

	if utils.ExperimentalBuild() {
		logrus.Warn("Running experimental build")
	}

	logrus.SetFormatter(&logrus.TextFormatter{
		TimestampFormat: jsonlog.RFC3339NanoFixed,
		DisableColors:   cli.Config.RawLogs,
	})

	if err := setDefaultUmask(); err != nil {
		logrus.Fatalf("Failed to set umask: %v", err)
	}

	if len(cli.LogConfig.Config) > 0 {
		if err := logger.ValidateLogOpts(cli.LogConfig.Type, cli.LogConfig.Config); err != nil {
			logrus.Fatalf("Failed to set log opts: %v", err)
		}
	}

	var pfile *pidfile.PIDFile
	if cli.Pidfile != "" {
		pf, err := pidfile.New(cli.Pidfile)
		if err != nil {
			logrus.Fatalf("Error starting daemon: %v", err)
		}
		pfile = pf
		defer func() {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}()
	}

	serverConfig := &apiserver.Config{
		Logging:     true,
		SocketGroup: cli.Config.SocketGroup,
		Version:     dockerversion.Version,
	}
	serverConfig = setPlatformServerConfig(serverConfig, cli.Config)

	if cli.Config.TLS {
		tlsOptions := tlsconfig.Options{
			CAFile:   cli.Config.CommonTLSOptions.CAFile,
			CertFile: cli.Config.CommonTLSOptions.CertFile,
			KeyFile:  cli.Config.CommonTLSOptions.KeyFile,
		}

		if cli.Config.TLSVerify {
			// server requires and verifies client's certificate
			tlsOptions.ClientAuth = tls.RequireAndVerifyClientCert
		}
		tlsConfig, err := tlsconfig.Server(tlsOptions)
		if err != nil {
			logrus.Fatal(err)
		}
		serverConfig.TLSConfig = tlsConfig
	}

	if len(cli.Config.Hosts) == 0 {
		cli.Config.Hosts = make([]string, 1)
	}

	api := apiserver.New(serverConfig)

	for i := 0; i < len(cli.Config.Hosts); i++ {
		var err error
		if cli.Config.Hosts[i], err = opts.ParseHost(cli.Config.TLS, cli.Config.Hosts[i]); err != nil {
			logrus.Fatalf("error parsing -H %s : %v", cli.Config.Hosts[i], err)
		}

		protoAddr := cli.Config.Hosts[i]
		protoAddrParts := strings.SplitN(protoAddr, "://", 2)
		if len(protoAddrParts) != 2 {
			logrus.Fatalf("bad format %s, expected PROTO://ADDR", protoAddr)
		}

		proto := protoAddrParts[0]
		addr := protoAddrParts[1]

		// It's a bad idea to bind to TCP without tlsverify.
		if proto == "tcp" && (serverConfig.TLSConfig == nil || serverConfig.TLSConfig.ClientAuth != tls.RequireAndVerifyClientCert) {
			logrus.Warn("[!] DON'T BIND ON ANY IP ADDRESS WITHOUT setting -tlsverify IF YOU DON'T KNOW WHAT YOU'RE DOING [!]")
		}
		l, err := listeners.Init(proto, addr, serverConfig.SocketGroup, serverConfig.TLSConfig)
		if err != nil {
			logrus.Fatal(err)
		}
		// If we're binding to a TCP port, make sure that a container doesn't try to use it.
		if proto == "tcp" {
			if err := allocateDaemonPort(addr); err != nil {
				logrus.Fatal(err)
			}
		}
		logrus.Debugf("Listener created for HTTP on %s (%s)", protoAddrParts[0], protoAddrParts[1])
		api.Accept(protoAddrParts[1], l...)
	}

	if err := migrateKey(); err != nil {
		logrus.Fatal(err)
	}
	cli.TrustKeyPath = cli.commonFlags.TrustKey

	registryService := registry.NewService(cli.Config.ServiceOptions)
	containerdRemote, err := libcontainerd.New(cli.getLibcontainerdRoot(), cli.getPlatformRemoteOptions()...)
	if err != nil {
		logrus.Fatal(err)
	}

	d, err := daemon.NewDaemon(cli.Config, registryService, containerdRemote)
	if err != nil {
		if pfile != nil {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}
		logrus.Fatalf("Error starting daemon: %v", err)
	}

	logrus.Info("Daemon has completed initialization")

	logrus.WithFields(logrus.Fields{
		"version":     dockerversion.Version,
		"commit":      dockerversion.GitCommit,
		"graphdriver": d.GraphDriverName(),
	}).Info("Docker daemon")

	cli.initMiddlewares(api, serverConfig)
	initRouter(api, d)

	reload := func(config *daemon.Config) {
		if err := d.Reload(config); err != nil {
			logrus.Errorf("Error reconfiguring the daemon: %v", err)
			return
		}
		if config.IsValueSet("debug") {
			debugEnabled := utils.IsDebugEnabled()
			switch {
			case debugEnabled && !config.Debug: // disable debug
				utils.DisableDebug()
				api.DisableProfiler()
			case config.Debug && !debugEnabled: // enable debug
				utils.EnableDebug()
				api.EnableProfiler()
			}

		}
	}

	setupConfigReloadTrap(*cli.configFile, flags, reload)

	// The serve API routine never exits unless an error occurs
	// We need to start it as a goroutine and wait on it so
	// daemon doesn't exit
	serveAPIWait := make(chan error)
	go api.Wait(serveAPIWait)

	signal.Trap(func() {
		api.Close()
		<-serveAPIWait
		shutdownDaemon(d, 15)
		if pfile != nil {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}
	})

	// after the daemon is done setting up we can notify systemd api
	notifySystem()

	// Daemon is fully initialized and handling API traffic
	// Wait for serve API to complete
	errAPI := <-serveAPIWait
	shutdownDaemon(d, 15)
	containerdRemote.Cleanup()
	if errAPI != nil {
		if pfile != nil {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}
		logrus.Fatalf("Shutting down due to ServeAPI error: %v", errAPI)
	}
}
Пример #10
0
// CmdDaemon is the daemon command, called the raw arguments after `docker daemon`.
func (cli *DaemonCli) CmdDaemon(args ...string) error {
	// warn from uuid package when running the daemon
	uuid.Loggerf = logrus.Warnf

	//调整一下daemon的启动方式
	if !commonFlags.FlagSet.IsEmpty() || !clientFlags.FlagSet.IsEmpty() {
		// deny `docker -D daemon`
		illegalFlag := getGlobalFlag()
		fmt.Fprintf(os.Stderr, "invalid flag '-%s'.\nSee 'docker daemon --help'.\n", illegalFlag.Names[0])
		os.Exit(1)
	} else {
		// allow new form `docker daemon -D`
		flag.Merge(cli.flags, commonFlags.FlagSet)
	}

	configFile := cli.flags.String([]string{daemonConfigFileFlag}, defaultDaemonConfigFile, "Daemon configuration file")

	//匹配配置参数
	cli.flags.ParseFlags(args, true)
	//配置参数生效
	commonFlags.PostParse()

	if commonFlags.TrustKey == "" {
		commonFlags.TrustKey = filepath.Join(getDaemonConfDir(), defaultTrustKeyFile)
	}
	cliConfig, err := loadDaemonCliConfig(cli.Config, cli.flags, commonFlags, *configFile)
	if err != nil {
		fmt.Fprint(os.Stderr, err)
		os.Exit(1)
	}
	cli.Config = cliConfig

	if cli.Config.Debug {
		utils.EnableDebug()
	}

	if utils.ExperimentalBuild() {
		logrus.Warn("Running experimental build")
	}

	logrus.SetFormatter(&logrus.TextFormatter{
		TimestampFormat: jsonlog.RFC3339NanoFixed,
		DisableColors:   cli.Config.RawLogs,
	})

	if err := setDefaultUmask(); err != nil {
		logrus.Fatalf("Failed to set umask: %v", err)
	}

	if len(cli.LogConfig.Config) > 0 {
		if err := logger.ValidateLogOpts(cli.LogConfig.Type, cli.LogConfig.Config); err != nil {
			logrus.Fatalf("Failed to set log opts: %v", err)
		}
	}

	var pfile *pidfile.PIDFile
	if cli.Pidfile != "" {
		pf, err := pidfile.New(cli.Pidfile)
		if err != nil {
			logrus.Fatalf("Error starting daemon: %v", err)
		}
		pfile = pf
		defer func() {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}()
	}

	//定义apiserver的配置,包括认证、日志输出、版本等。
	serverConfig := &apiserver.Config{
		AuthorizationPluginNames: cli.Config.AuthorizationPlugins,
		Logging:                  true,
		SocketGroup:              cli.Config.SocketGroup,
		Version:                  dockerversion.Version,
	}
	serverConfig = setPlatformServerConfig(serverConfig, cli.Config)

	if cli.Config.TLS {
		tlsOptions := tlsconfig.Options{
			CAFile:   cli.Config.CommonTLSOptions.CAFile,
			CertFile: cli.Config.CommonTLSOptions.CertFile,
			KeyFile:  cli.Config.CommonTLSOptions.KeyFile,
		}

		if cli.Config.TLSVerify {
			// server requires and verifies client's certificate
			tlsOptions.ClientAuth = tls.RequireAndVerifyClientCert
		}
		tlsConfig, err := tlsconfig.Server(tlsOptions)
		if err != nil {
			logrus.Fatal(err)
		}
		serverConfig.TLSConfig = tlsConfig
	}

	if len(cli.Config.Hosts) == 0 {
		cli.Config.Hosts = make([]string, 1)
	}

	//定义一个新的apiserver。
	//apiServer是一个这样的结构(api/server/server.go):
	/*
	type Server struct {
	    cfg           *Config
	    servers       []*HTTPServer
	    routers       []router.Router
	    authZPlugins  []authorization.Plugin
	    routerSwapper *routerSwapper
           }
	*/
	api := apiserver.New(serverConfig)

	for i := 0; i < len(cli.Config.Hosts); i++ {
		var err error
		if cli.Config.Hosts[i], err = opts.ParseHost(cli.Config.TLS, cli.Config.Hosts[i]); err != nil {
			logrus.Fatalf("error parsin
			g -H %s : %v", cli.Config.Hosts[i], err)
		}

		protoAddr := cli.Config.Hosts[i]
		protoAddrParts := strings.SplitN(protoAddr, "://", 2)
		if len(protoAddrParts) != 2 {
			logrus.Fatalf("bad format %s, expected PROTO://ADDR", protoAddr)
		}
		l, err := listeners.Init(protoAddrParts[0], protoAddrParts[1], serverConfig.SocketGroup, serverConfig.TLSConfig)
		if err != nil {
			logrus.Fatal(err)
		}

		logrus.Debugf("Listener created for HTTP on %s (%s)", protoAddrParts[0], protoAddrParts[1])
		
		//初始化api的servers数组,里面放着的都是httpserver类型。此时也没有具体的运行什么
		api.Accept(protoAddrParts[1], l...)
	}

	if err := migrateKey(); err != nil {
		logrus.Fatal(err)
	}
	cli.TrustKeyPath = commonFlags.TrustKey

           //创建镜像仓库服务
	registryService := registry.NewService(cli.Config.ServiceOptions)

	//初始化libcontainer。比如在linux中,就会调用libcontainerd/remote_linux.go中的New方法。
	
	containerdRemote, err := libcontainerd.New(filepath.Join(cli.Config.ExecRoot, "libcontainerd"), cli.getPlatformRemoteOptions()...)
	if err != nil {
		logrus.Fatal(err)
	}

           //初始化守护进程使得能够服务。需要输入仓库服务和libcontainerd服务的参数。
	//返回的d是Daemon类型:
	/*
	type Daemon struct {
	ID                        string
	repository                string
	containers                container.Store
	execCommands              *exec.Store
	referenceStore            reference.Store
	downloadManager           *xfer.LayerDownloadManager
	uploadManager             *xfer.LayerUploadManager
	distributionMetadataStore dmetadata.Store
	trustKey                  libtrust.PrivateKey
	idIndex                   *truncindex.TruncIndex
	configStore               *Config
	statsCollector            *statsCollector
	defaultLogConfig          containertypes.LogConfig
	RegistryService           *registry.Service
	EventsService             *events.Events
	netController             libnetwork.NetworkController
	volumes                   *store.VolumeStore
	discoveryWatcher          discoveryReloader
	root                      string
	seccompEnabled            bool
	shutdown                  bool
	uidMaps                   []idtools.IDMap
	gidMaps                   []idtools.IDMap
	layerStore                layer.Store
	imageStore                image.Store
	nameIndex                 *registrar.Registrar
	linkIndex                 *linkIndex
	containerd                libcontainerd.Client
	defaultIsolation          containertypes.Isolation // Default isolation mode on Windows
           }
	*/
	d, err := daemon.NewDaemon(cli.Config, registryService, containerdRemote)
	if err != nil {
		if pfile != nil {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}
		logrus.Fatalf("Error starting daemon: %v", err)
	}

	logrus.Info("Daemon has completed initialization")

	logrus.WithFields(logrus.Fields{
		"version":     dockerversion.Version,
		"commit":      dockerversion.GitCommit,
		"graphdriver": d.GraphDriverName(),
	}).Info("Docker daemon")

	//初始化http的路由,这个路由设计的非常易懂,所有的路由及处理函数的映射关系
	//请见api/server/router/文件夹中的内容。有类似这样的内容:
	//router.NewPostRoute("/containers/create", r.postContainersCreate),
	//其中,对应的处理函数postContainersCreate在api/server/router/container/container_routes.go
	//但是,实际上这个函数也不做具体的事情,他交给backend去做,就是daemon去做
	/*
	ccr, err := s.backend.ContainerCreate(types.ContainerCreateConfig{
		Name:             name,
		Config:           config,
		HostConfig:       hostConfig,
		NetworkingConfig: networkingConfig,
		AdjustCPUShares:  adjustCPUShares,
	})
	 */
	//其中的ContainerCreate在
	initRouter(api, d)

	reload := func(config *daemon.Config) {
		if err := d.Reload(config); err != nil {
			logrus.Errorf("Error reconfiguring the daemon: %v", err)
			return
		}
		if config.IsValueSet("debug") {
			debugEnabled := utils.IsDebugEnabled()
			switch {
			case debugEnabled && !config.Debug: // disable debug
				utils.DisableDebug()
				api.DisableProfiler()
			case config.Debug && !debugEnabled: // enable debug
				utils.EnableDebug()
				api.EnableProfiler()
			}

		}
	}

	setupConfigReloadTrap(*configFile, cli.flags, reload)

	// The serve API routine never exits unless an error occurs
	// We need to start it as a goroutine and wait on it so
	// daemon doesn't exit
	//设置一个传输apiServer状态的通道
	serveAPIWait := make(chan error)
	//重新开启一个goroutine作为httpServer。
	//具体的请查看api/server/server.go中的方法func (s *Server) serveAPI() error 
	go api.Wait(serveAPIWait)

	signal.Trap(func() {
		api.Close()
		<-serveAPIWait
		shutdownDaemon(d, 15)
		if pfile != nil {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}
	})

	// after the daemon is done setting up we can notify systemd api
	notifySystem()

	// Daemon is fully initialized and handling API traffic
	// Wait for serve API to complete
	//<-表示接受通道值,只有当通道中有值的时候,才会返回。
	//也就是说主线程一直在等待api.wait的goroutine启动apiServer之后的返回才会进行。
	errAPI := <-serveAPIWait
	//当接收到返回(返回就是错误了),开始清理进程。
	shutdownDaemon(d, 15)
	containerdRemote.Cleanup()
	if errAPI != nil {
		if pfile != nil {
			if err := pfile.Remove(); err != nil {
				logrus.Error(err)
			}
		}
		logrus.Fatalf("Shutting down due to ServeAPI error: %v", errAPI)
	}
	return nil
}