func (cli *DaemonCli) start(opts daemonOptions) (err error) { stopc := make(chan bool) defer close(stopc) // warn from uuid package when running the daemon uuid.Loggerf = logrus.Warnf opts.common.SetDefaultOptions(opts.flags) if opts.common.TrustKey == "" { opts.common.TrustKey = filepath.Join( getDaemonConfDir(), cliflags.DefaultTrustKeyFile) } if cli.Config, err = loadDaemonCliConfig(opts); err != nil { return err } cli.configFile = &opts.configFile cli.flags = opts.flags 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 { return fmt.Errorf("Failed to set umask: %v", err) } if len(cli.LogConfig.Config) > 0 { if err := logger.ValidateLogOpts(cli.LogConfig.Type, cli.LogConfig.Config); err != nil { return fmt.Errorf("Failed to set log opts: %v", err) } } if cli.Pidfile != "" { pf, err := pidfile.New(cli.Pidfile) if err != nil { return fmt.Errorf("Error starting daemon: %v", err) } defer func() { if err := pf.Remove(); err != nil { logrus.Error(err) } }() } serverConfig := &apiserver.Config{ Logging: true, SocketGroup: cli.Config.SocketGroup, Version: dockerversion.Version, EnableCors: cli.Config.EnableCors, CorsHeaders: cli.Config.CorsHeaders, } 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 { return err } serverConfig.TLSConfig = tlsConfig } if len(cli.Config.Hosts) == 0 { cli.Config.Hosts = make([]string, 1) } api := apiserver.New(serverConfig) cli.api = api for i := 0; i < len(cli.Config.Hosts); i++ { var err error if cli.Config.Hosts[i], err = dopts.ParseHost(cli.Config.TLS, cli.Config.Hosts[i]); err != nil { return fmt.Errorf("error parsing -H %s : %v", cli.Config.Hosts[i], err) } protoAddr := cli.Config.Hosts[i] protoAddrParts := strings.SplitN(protoAddr, "://", 2) if len(protoAddrParts) != 2 { return fmt.Errorf("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 [!]") } ls, err := listeners.Init(proto, addr, serverConfig.SocketGroup, serverConfig.TLSConfig) if err != nil { return err } ls = wrapListeners(proto, ls) // 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 { return err } } logrus.Debugf("Listener created for HTTP on %s (%s)", proto, addr) api.Accept(addr, ls...) } if err := migrateKey(); err != nil { return err } // FIXME: why is this down here instead of with the other TrustKey logic above? cli.TrustKeyPath = opts.common.TrustKey registryService := registry.NewService(cli.Config.ServiceOptions) containerdRemote, err := libcontainerd.New(cli.getLibcontainerdRoot(), cli.getPlatformRemoteOptions()...) if err != nil { return err } signal.Trap(func() { cli.stop() <-stopc // wait for daemonCli.start() to return }) d, err := daemon.NewDaemon(cli.Config, registryService, containerdRemote) if err != nil { return fmt.Errorf("Error starting daemon: %v", err) } name, _ := os.Hostname() c, err := cluster.New(cluster.Config{ Root: cli.Config.Root, Name: name, Backend: d, NetworkSubnetsProvider: d, DefaultAdvertiseAddr: cli.Config.SwarmDefaultAdvertiseAddr, RuntimeRoot: cli.getSwarmRunRoot(), }) if err != nil { logrus.Fatalf("Error creating cluster component: %v", err) } // Restart all autostart containers which has a swarm endpoint // and is not yet running now that we have successfully // initialized the cluster. d.RestartSwarmContainers() logrus.Info("Daemon has completed initialization") logrus.WithFields(logrus.Fields{ "version": dockerversion.Version, "commit": dockerversion.GitCommit, "graphdriver": d.GraphDriverName(), }).Info("Docker daemon") cli.d = d // initMiddlewares needs cli.d to be populated. Dont change this init order. cli.initMiddlewares(api, serverConfig) initRouter(api, d, c) cli.setupConfigReloadTrap() // 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) // 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 c.Cleanup() shutdownDaemon(d) containerdRemote.Cleanup() if errAPI != nil { return fmt.Errorf("Shutting down due to ServeAPI error: %v", errAPI) } return nil }
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) } }
// 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) containerdRemote, err := libcontainerd.New(filepath.Join(cli.Config.ExecRoot, "libcontainerd"), 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") 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) 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 }
// 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 }