Golang log.Fatalf函数代码示例

func getConfig(flagset *flag.FlagSet, userCfgFile string) (*config.Config, error) {
	opts := globalconf.Options{EnvPrefix: "FLEET_"}

	if userCfgFile != "" {
		// Fail hard if a user-provided config is not usable
		fi, err := os.Stat(userCfgFile)
		if err != nil {
			log.Fatalf("Unable to use config file %s: %v", userCfgFile, err)
		}
		if fi.IsDir() {
			log.Fatalf("Provided config %s is a directory, not a file", userCfgFile)
		}

		log.Infof("Using provided config file %s", userCfgFile)
		opts.Filename = userCfgFile

	} else if _, err := os.Stat(DefaultConfigFile); err == nil {
		log.Infof("Using default config file %s", DefaultConfigFile)
		opts.Filename = DefaultConfigFile
	} else {
		log.Infof("No provided or default config file found - proceeding without")
	}

	gconf, err := globalconf.NewWithOptions(&opts)
	if err != nil {
		return nil, err
	}

	gconf.ParseSet("", flagset)

	cfg := config.Config{
		Verbosity:               (*flagset.Lookup("verbosity")).Value.(flag.Getter).Get().(int),
		EtcdServers:             (*flagset.Lookup("etcd_servers")).Value.(flag.Getter).Get().(pkg.StringSlice),
		EtcdKeyPrefix:           (*flagset.Lookup("etcd_key_prefix")).Value.(flag.Getter).Get().(string),
		EtcdKeyFile:             (*flagset.Lookup("etcd_keyfile")).Value.(flag.Getter).Get().(string),
		EtcdCertFile:            (*flagset.Lookup("etcd_certfile")).Value.(flag.Getter).Get().(string),
		EtcdCAFile:              (*flagset.Lookup("etcd_cafile")).Value.(flag.Getter).Get().(string),
		EtcdRequestTimeout:      (*flagset.Lookup("etcd_request_timeout")).Value.(flag.Getter).Get().(float64),
		EngineReconcileInterval: (*flagset.Lookup("engine_reconcile_interval")).Value.(flag.Getter).Get().(float64),
		PublicIP:                (*flagset.Lookup("public_ip")).Value.(flag.Getter).Get().(string),
		RawMetadata:             (*flagset.Lookup("metadata")).Value.(flag.Getter).Get().(string),
		AgentTTL:                (*flagset.Lookup("agent_ttl")).Value.(flag.Getter).Get().(string),
		VerifyUnits:             (*flagset.Lookup("verify_units")).Value.(flag.Getter).Get().(bool),
		TokenLimit:              (*flagset.Lookup("token_limit")).Value.(flag.Getter).Get().(int),
		AuthorizedKeysFile:      (*flagset.Lookup("authorized_keys_file")).Value.(flag.Getter).Get().(string),
	}

	if cfg.VerifyUnits {
		log.Error("Config option verify_units is no longer supported - ignoring")
	}
	if len(cfg.AuthorizedKeysFile) > 0 {
		log.Error("Config option authorized_keys_file is no longer supported - ignoring")
	}

	if cfg.Verbosity > 0 {
		log.EnableDebug()
	}

	return &cfg, nil
}

func (r *RegistryMux) EngineChanged(newEngine machine.MachineState) {
	r.handlingEngineChange.Lock()
	defer r.handlingEngineChange.Unlock()

	stopServer := false
	if r.currentEngine.ID != newEngine.ID {
		stopServer = true
	}
	r.currentEngine = newEngine
	log.Infof("Engine changed, checking capabilities %+v", newEngine)
	if r.localMachine.State().Capabilities.Has(machine.CapGRPC) {
		if r.rpcserver != nil && ((r.rpcRegistry != nil && !r.rpcRegistry.IsRegistryReady()) || stopServer) {
			// If the engine changed, we need to stop the rpc server
			r.rpcserver.Stop()
			r.rpcserver = nil
		}
		if newEngine.ID == r.localMachine.State().ID {
			if r.rpcserver == nil {
				// start rpc server
				log.Infof("Starting rpc server...\n")
				var err error
				r.rpcserver, err = NewRPCServer(r.etcdRegistry, newEngine.PublicIP)
				if err != nil {
					log.Fatalf("Unable to create rpc server %+v", err)
				}

				go func() {
					errc := make(chan error, 1)
					if errc <- r.rpcserver.Start(); <-errc != nil {
						log.Fatalf("Failed to serve gRPC requests on listener: %v", <-errc)
					}
				}()
			}

		}
		if newEngine.Capabilities.Has(machine.CapGRPC) {
			if r.rpcRegistry != nil && r.rpcRegistry.IsRegistryReady() {
				log.Infof("Reusing gRPC engine, connection is READY\n")
				r.currentRegistry = r.rpcRegistry
			} else {
				log.Infof("New engine supports gRPC, connecting\n")
				r.rpcRegistry = NewRPCRegistry(r.rpcDialer)
				// connect to rpc registry
				r.rpcRegistry.Connect()
				r.currentRegistry = r.rpcRegistry
			}
		} else {
			log.Infof("Falling back to etcd registry\n")
			if r.rpcserver != nil {
				// If the engine changed to a non gRPC leader, we need to stop the server
				r.rpcserver.Stop()
			}
			r.currentRegistry = r.etcdRegistry
		}

	} else {
		log.Infof("Falling back to etcd registry\n")
		r.currentRegistry = r.etcdRegistry
	}
}

func (r *RPCRegistry) Connect() {
	// We want the connection operation to block and constantly reconnect using grpc backoff
	log.Info("Starting gRPC connection to fleet-engine...")
	ep_engines := []string{":fleet-engine:"}
	r.balancer = newSimpleBalancer(ep_engines)
	connection, err := grpc.Dial(ep_engines[0],
		grpc.WithTimeout(12*time.Second), grpc.WithInsecure(),
		grpc.WithDialer(r.dialer), grpc.WithBlock(), grpc.WithBalancer(r.balancer))
	if err != nil {
		log.Fatalf("Unable to dial to registry: %s", err)
	}
	r.registryConn = connection
	r.registryClient = pb.NewRegistryClient(r.registryConn)
	log.Info("Connected succesfully to fleet-engine via grpc!")
}

func main() {
	userset := flag.NewFlagSet("fleet", flag.ExitOnError)
	printVersion := userset.Bool("version", false, "Print the version and exit")
	cfgPath := userset.String("config", "", fmt.Sprintf("Path to config file. Fleet will look for a config at %s by default.", DefaultConfigFile))

	err := userset.Parse(os.Args[1:])
	if err == flag.ErrHelp {
		userset.Usage()
		os.Exit(1)
	}

	args := userset.Args()
	if len(args) == 1 && args[0] == "version" {
		*printVersion = true
	} else if len(args) != 0 {
		userset.Usage()
		os.Exit(1)
	}

	if *printVersion {
		fmt.Println("fleetd version", version.Version)
		os.Exit(0)
	}

	log.Infof("Starting fleetd version %v", version.Version)

	cfgset := flag.NewFlagSet("fleet", flag.ExitOnError)
	cfgset.Int("verbosity", 0, "Logging level")
	cfgset.Var(&stringSlice{}, "etcd_servers", "List of etcd endpoints")
	cfgset.String("etcd_keyfile", "", "SSL key file used to secure etcd communication")
	cfgset.String("etcd_certfile", "", "SSL certification file used to secure etcd communication")
	cfgset.String("etcd_cafile", "", "SSL Certificate Authority file used to secure etcd communication")
	cfgset.String("etcd_key_prefix", registry.DefaultKeyPrefix, "Keyspace for fleet data in etcd")
	cfgset.Float64("etcd_request_timeout", 1.0, "Amount of time in seconds to allow a single etcd request before considering it failed.")
	cfgset.Float64("engine_reconcile_interval", 2.0, "Interval at which the engine should reconcile the cluster schedule in etcd.")
	cfgset.String("public_ip", "", "IP address that fleet machine should publish")
	cfgset.String("metadata", "", "List of key-value metadata to assign to the fleet machine")
	cfgset.String("agent_ttl", agent.DefaultTTL, "TTL in seconds of fleet machine state in etcd")
	cfgset.Bool("verify_units", false, "DEPRECATED - This option is ignored")
	cfgset.String("authorized_keys_file", "", "DEPRECATED - This option is ignored")

	globalconf.Register("", cfgset)
	cfg, err := getConfig(cfgset, *cfgPath)
	if err != nil {
		log.Fatalf(err.Error())
	}

	log.Debugf("Creating Server")
	srv, err := server.New(*cfg)
	if err != nil {
		log.Fatalf("Failed creating Server: %v", err.Error())
	}
	srv.Run()

	reconfigure := func() {
		log.Infof("Reloading configuration from %s", *cfgPath)

		cfg, err := getConfig(cfgset, *cfgPath)
		if err != nil {
			log.Fatalf(err.Error())
		}

		log.Infof("Restarting server components")
		srv.Stop()

		srv, err = server.New(*cfg)
		if err != nil {
			log.Fatalf(err.Error())
		}
		srv.Run()
	}

	shutdown := func() {
		log.Infof("Gracefully shutting down")
		srv.Stop()
		srv.Purge()
		os.Exit(0)
	}

	writeState := func() {
		log.Infof("Dumping server state")

		encoded, err := json.Marshal(srv)
		if err != nil {
			log.Errorf("Failed to dump server state: %v", err)
			return
		}

		if _, err := os.Stdout.Write(encoded); err != nil {
			log.Errorf("Failed to dump server state: %v", err)
			return
		}

		os.Stdout.Write([]byte("\n"))

		log.Debugf("Finished dumping server state")
	}

	signals := map[os.Signal]func(){
		syscall.SIGHUP:  reconfigure,
//.........这里部分代码省略.........

func Main() {
	userset := flag.NewFlagSet("fleet", flag.ExitOnError)
	printVersion := userset.Bool("version", false, "Print the version and exit")
	cfgPath := userset.String("config", "", fmt.Sprintf("Path to config file. Fleet will look for a config at %s by default.", DefaultConfigFile))

	userset.Usage = func() {
		fmt.Fprintf(os.Stderr, "%s\nUsage of %s:\n", FleetdDescription, os.Args[0])
		userset.PrintDefaults()
	}

	err := userset.Parse(os.Args[1:])
	if err != nil {
		userset.Usage()
		os.Exit(1)
	}

	args := userset.Args()
	if len(args) > 0 {
		// support `fleetd version` the same as `fleetd --version`
		if args[0] == "version" {
			*printVersion = true
		} else {
			fmt.Fprintf(os.Stderr, "%s takes no arguments. Did you mean to invoke fleetctl instead?\n", os.Args[0])
			userset.Usage()
			os.Exit(1)
		}
	}

	if *printVersion {
		fmt.Println("fleetd version", version.Version)
		os.Exit(0)
	}

	log.Infof("Starting fleetd version %v", version.Version)

	cfgset := flag.NewFlagSet("fleet", flag.ExitOnError)
	cfgset.Int("verbosity", 0, "Logging level")
	cfgset.Var(&pkg.StringSlice{"http://127.0.0.1:2379", "http://127.0.0.1:4001"}, "etcd_servers", "List of etcd endpoints")
	cfgset.String("etcd_username", "", "username for secure etcd communication")
	cfgset.String("etcd_password", "", "password for secure etcd communication")
	cfgset.String("etcd_keyfile", "", "SSL key file used to secure etcd communication")
	cfgset.String("etcd_certfile", "", "SSL certification file used to secure etcd communication")
	cfgset.String("etcd_cafile", "", "SSL Certificate Authority file used to secure etcd communication")
	cfgset.String("etcd_key_prefix", registry.DefaultKeyPrefix, "Keyspace for fleet data in etcd")
	cfgset.Float64("etcd_request_timeout", 1.0, "Amount of time in seconds to allow a single etcd request before considering it failed.")
	cfgset.Float64("engine_reconcile_interval", 2.0, "Interval at which the engine should reconcile the cluster schedule in etcd.")
	cfgset.String("public_ip", "", "IP address that fleet machine should publish")
	cfgset.String("metadata", "", "List of key-value metadata to assign to the fleet machine")
	cfgset.String("agent_ttl", agent.DefaultTTL, "TTL in seconds of fleet machine state in etcd")
	cfgset.String("units_directory", "/run/fleet/units/", "Path to the fleet units directory")
	cfgset.Bool("systemd_user", false, "When true use systemd --user)")
	cfgset.Int("token_limit", 100, "Maximum number of entries per page returned from API requests")
	cfgset.Bool("enable_grpc", false, "When possible, uses grpc to communicate between engine and agent")
	cfgset.Bool("disable_engine", false, "Disable the engine entirely, use with care")
	cfgset.Bool("disable_watches", false, "Disable the use of etcd watches. Increases scheduling latency")
	cfgset.Bool("verify_units", false, "DEPRECATED - This option is ignored")
	cfgset.String("authorized_keys_file", "", "DEPRECATED - This option is ignored")

	globalconf.Register("", cfgset)
	cfg, err := getConfig(cfgset, *cfgPath)
	if err != nil {
		log.Fatal(err)
	}

	log.Debugf("Creating Server")
	srv, err := server.New(*cfg, nil)
	if err != nil {
		log.Fatalf("Failed creating Server: %v", err)
	}
	srv.Run()

	srvMutex := sync.Mutex{}

	reconfigure := func() {
		log.Infof("Reloading configuration from %s", *cfgPath)

		srvMutex.Lock()
		defer srvMutex.Unlock()

		cfg, err := getConfig(cfgset, *cfgPath)
		if err != nil {
			log.Fatal(err)
		}

		log.Infof("Restarting server components")
		srv.SetReconfigServer(true)

		// Get Server.listeners[] to keep it for a new server,
		// before killing the old server.
		oldListeners := srv.GetApiServerListeners()

		srv.Kill()

		// The new server takes the original listeners.
		srv, err = server.New(*cfg, oldListeners)
		if err != nil {
			log.Fatal(err)
		}

		srv.Run()
//.........这里部分代码省略.........