Golang flags.URLsFromFlags函数代码示例

func (cfg *config) configFromCmdLine() error {
	err := flags.SetFlagsFromEnv("ETCD", cfg.FlagSet)
	if err != nil {
		plog.Fatalf("%v", err)
	}

	flags.SetBindAddrFromAddr(cfg.FlagSet, "peer-bind-addr", "peer-addr")
	flags.SetBindAddrFromAddr(cfg.FlagSet, "bind-addr", "addr")

	cfg.lpurls, err = flags.URLsFromFlags(cfg.FlagSet, "listen-peer-urls", "peer-bind-addr", cfg.peerTLSInfo)
	if err != nil {
		return err
	}
	cfg.apurls, err = flags.URLsFromFlags(cfg.FlagSet, "initial-advertise-peer-urls", "peer-addr", cfg.peerTLSInfo)
	if err != nil {
		return err
	}
	cfg.lcurls, err = flags.URLsFromFlags(cfg.FlagSet, "listen-client-urls", "bind-addr", cfg.clientTLSInfo)
	if err != nil {
		return err
	}
	cfg.acurls, err = flags.URLsFromFlags(cfg.FlagSet, "advertise-client-urls", "addr", cfg.clientTLSInfo)
	if err != nil {
		return err
	}

	return cfg.validateConfig(func(field string) bool {
		return flags.IsSet(cfg.FlagSet, field)
	})
}

func (cfg *config) Parse(arguments []string) error {
	perr := cfg.FlagSet.Parse(arguments)
	switch perr {
	case nil:
	case flag.ErrHelp:
		os.Exit(0)
	default:
		os.Exit(2)
	}

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

	err := flags.SetFlagsFromEnv(cfg.FlagSet)
	if err != nil {
		log.Fatalf("etcd: %v", err)
	}

	set := make(map[string]bool)
	cfg.FlagSet.Visit(func(f *flag.Flag) {
		set[f.Name] = true
	})
	nSet := 0
	for _, v := range []bool{set["discovery"], set["initial-cluster"], set["discovery-srv"]} {
		if v {
			nSet += 1
		}
	}
	if nSet > 1 {
		return ErrConflictBootstrapFlags
	}

	cfg.lpurls, err = flags.URLsFromFlags(cfg.FlagSet, "listen-peer-urls", "peer-bind-addr", cfg.peerTLSInfo)
	if err != nil {
		return err
	}
	cfg.apurls, err = flags.URLsFromFlags(cfg.FlagSet, "initial-advertise-peer-urls", "peer-addr", cfg.peerTLSInfo)
	if err != nil {
		return err
	}
	cfg.lcurls, err = flags.URLsFromFlags(cfg.FlagSet, "listen-client-urls", "bind-addr", cfg.clientTLSInfo)
	if err != nil {
		return err
	}
	cfg.acurls, err = flags.URLsFromFlags(cfg.FlagSet, "advertise-client-urls", "addr", cfg.clientTLSInfo)
	if err != nil {
		return err
	}

	if err := cfg.resolveUrls(); err != nil {
		return errors.New("cannot resolve DNS hostnames.")
	}

	return nil
}

// setupCluster sets up the cluster definition for bootstrap or discovery.
func setupCluster() (*etcdserver.Cluster, error) {
	set := make(map[string]bool)
	fs.Visit(func(f *flag.Flag) {
		set[f.Name] = true
	})
	if set["discovery"] && set["initial-cluster"] {
		return nil, fmt.Errorf("both discovery and bootstrap-config are set")
	}
	apurls, err := flags.URLsFromFlags(fs, "initial-advertise-peer-urls", "addr", peerTLSInfo)
	if err != nil {
		return nil, err
	}

	var cls *etcdserver.Cluster
	switch {
	case set["discovery"]:
		clusterStr := genClusterString(*name, apurls)
		cls, err = etcdserver.NewClusterFromString(*durl, clusterStr)
	case set["initial-cluster"]:
		fallthrough
	default:
		// We're statically configured, and cluster has appropriately been set.
		// Try to configure by indexing the static cluster by name.
		cls, err = etcdserver.NewClusterFromString(*initialClusterName, *initialCluster)
	}
	return cls, err
}

// startProxy launches an HTTP proxy for client communication which proxies to other etcd nodes.
func startProxy() {
	cls, err := setupCluster()
	if err != nil {
		log.Fatalf("etcd: error setting up initial cluster: %v", err)
	}

	pt, err := transport.NewTransport(clientTLSInfo)
	if err != nil {
		log.Fatal(err)
	}

	// TODO(jonboulle): update peerURLs dynamically (i.e. when updating
	// clientURLs) instead of just using the initial fixed list here
	peerURLs := cls.PeerURLs()
	uf := func() []string {
		cls, err := etcdserver.GetClusterFromPeers(peerURLs)
		if err != nil {
			log.Printf("etcd: %v", err)
			return []string{}
		}
		return cls.ClientURLs()
	}
	ph := proxy.NewHandler(pt, uf)
	ph = &cors.CORSHandler{
		Handler: ph,
		Info:    corsInfo,
	}

	if string(*proxyFlag) == flags.ProxyValueReadonly {
		ph = proxy.NewReadonlyHandler(ph)
	}

	lcurls, err := flags.URLsFromFlags(fs, "listen-client-urls", "bind-addr", clientTLSInfo)
	if err != nil {
		log.Fatal(err.Error())
	}
	// Start a proxy server goroutine for each listen address
	for _, u := range lcurls {
		l, err := transport.NewListener(u.Host, clientTLSInfo)
		if err != nil {
			log.Fatal(err)
		}

		host := u.Host
		go func() {
			log.Print("etcd: proxy listening for client requests on ", host)
			log.Fatal(http.Serve(l, ph))
		}()
	}
}

func (cfg *config) Parse(arguments []string) error {
	perr := cfg.FlagSet.Parse(arguments)
	switch perr {
	case nil:
	case flag.ErrHelp:
		fmt.Println(flagsline)
		os.Exit(0)
	default:
		os.Exit(2)
	}
	if len(cfg.FlagSet.Args()) != 0 {
		return fmt.Errorf("'%s' is not a valid flag", cfg.FlagSet.Arg(0))
	}

	if cfg.printVersion {
		fmt.Printf("etcd Version: %s\n", version.Version)
		fmt.Printf("Git SHA: %s\n", version.GitSHA)
		fmt.Printf("Go Version: %s\n", runtime.Version())
		fmt.Printf("Go OS/Arch: %s/%s\n", runtime.GOOS, runtime.GOARCH)
		os.Exit(0)
	}

	err := flags.SetFlagsFromEnv("ETCD", cfg.FlagSet)
	if err != nil {
		plog.Fatalf("%v", err)
	}

	set := make(map[string]bool)
	cfg.FlagSet.Visit(func(f *flag.Flag) {
		set[f.Name] = true
	})
	nSet := 0
	for _, v := range []bool{set["discovery"], set["initial-cluster"], set["discovery-srv"]} {
		if v {
			nSet += 1
		}
	}
	if nSet > 1 {
		return ErrConflictBootstrapFlags
	}

	flags.SetBindAddrFromAddr(cfg.FlagSet, "peer-bind-addr", "peer-addr")
	flags.SetBindAddrFromAddr(cfg.FlagSet, "bind-addr", "addr")

	cfg.lpurls, err = flags.URLsFromFlags(cfg.FlagSet, "listen-peer-urls", "peer-bind-addr", cfg.peerTLSInfo)
	if err != nil {
		return err
	}
	cfg.apurls, err = flags.URLsFromFlags(cfg.FlagSet, "initial-advertise-peer-urls", "peer-addr", cfg.peerTLSInfo)
	if err != nil {
		return err
	}
	cfg.lcurls, err = flags.URLsFromFlags(cfg.FlagSet, "listen-client-urls", "bind-addr", cfg.clientTLSInfo)
	if err != nil {
		return err
	}
	cfg.acurls, err = flags.URLsFromFlags(cfg.FlagSet, "advertise-client-urls", "addr", cfg.clientTLSInfo)
	if err != nil {
		return err
	}

	// when etcd runs in member mode user needs to set --advertise-client-urls if --listen-client-urls is set.
	// TODO(yichengq): check this for joining through discovery service case
	mayFallbackToProxy := flags.IsSet(cfg.FlagSet, "discovery") && cfg.fallback.String() == fallbackFlagProxy
	mayBeProxy := cfg.proxy.String() != proxyFlagOff || mayFallbackToProxy
	if !mayBeProxy {
		if flags.IsSet(cfg.FlagSet, "listen-client-urls") && !flags.IsSet(cfg.FlagSet, "advertise-client-urls") {
			return errUnsetAdvertiseClientURLsFlag
		}
	}

	if 5*cfg.TickMs > cfg.ElectionMs {
		return fmt.Errorf("--election-timeout[%vms] should be at least as 5 times as --heartbeat-interval[%vms]", cfg.ElectionMs, cfg.TickMs)
	}
	if cfg.ElectionMs > maxElectionMs {
		return fmt.Errorf("--election-timeout[%vms] is too long, and should be set less than %vms", cfg.ElectionMs, maxElectionMs)
	}

	return nil
}

// startEtcd launches the etcd server and HTTP handlers for client/server communication.
func startEtcd() {
	cls, err := setupCluster()
	if err != nil {
		log.Fatalf("etcd: error setting up initial cluster: %v", err)
	}

	if *dir == "" {
		*dir = fmt.Sprintf("%v.etcd", *name)
		log.Printf("etcd: no data-dir provided, using default data-dir ./%s", *dir)
	}
	if err := os.MkdirAll(*dir, privateDirMode); err != nil {
		log.Fatalf("etcd: cannot create data directory: %v", err)
	}
	if err := fileutil.IsDirWriteable(*dir); err != nil {
		log.Fatalf("etcd: cannot write to data directory: %v", err)
	}

	pt, err := transport.NewTransport(peerTLSInfo)
	if err != nil {
		log.Fatal(err)
	}

	acurls, err := flags.URLsFromFlags(fs, "advertise-client-urls", "addr", clientTLSInfo)
	if err != nil {
		log.Fatal(err.Error())
	}
	cfg := &etcdserver.ServerConfig{
		Name:         *name,
		ClientURLs:   acurls,
		DataDir:      *dir,
		SnapCount:    *snapCount,
		Cluster:      cls,
		DiscoveryURL: *durl,
		ClusterState: *clusterState,
		Transport:    pt,
	}
	s := etcdserver.NewServer(cfg)
	s.Start()

	ch := &cors.CORSHandler{
		Handler: etcdhttp.NewClientHandler(s),
		Info:    corsInfo,
	}
	ph := etcdhttp.NewPeerHandler(s)

	lpurls, err := flags.URLsFromFlags(fs, "listen-peer-urls", "peer-bind-addr", peerTLSInfo)
	if err != nil {
		log.Fatal(err.Error())
	}

	for _, u := range lpurls {
		l, err := transport.NewListener(u.Host, peerTLSInfo)
		if err != nil {
			log.Fatal(err)
		}

		// Start the peer server in a goroutine
		urlStr := u.String()
		go func() {
			log.Print("etcd: listening for peers on ", urlStr)
			log.Fatal(http.Serve(l, ph))
		}()
	}

	lcurls, err := flags.URLsFromFlags(fs, "listen-client-urls", "bind-addr", clientTLSInfo)
	if err != nil {
		log.Fatal(err.Error())
	}

	// Start a client server goroutine for each listen address
	for _, u := range lcurls {
		l, err := transport.NewListener(u.Host, clientTLSInfo)
		if err != nil {
			log.Fatal(err)
		}

		urlStr := u.String()
		go func() {
			log.Print("etcd: listening for client requests on ", urlStr)
			log.Fatal(http.Serve(l, ch))
		}()
	}
}

// startProxy launches an HTTP proxy for client communication which proxies to other etcd nodes.
func startProxy() error {
	apurls, err := flags.URLsFromFlags(fs, "initial-advertise-peer-urls", "addr", peerTLSInfo)
	if err != nil {
		return err
	}
	cls, err := setupCluster(apurls)
	if err != nil {
		return fmt.Errorf("error setting up initial cluster: %v", err)
	}

	if *durl != "" {
		s, err := discovery.GetCluster(*durl, *dproxy)
		if err != nil {
			return err
		}
		if cls, err = etcdserver.NewClusterFromString(*durl, s); err != nil {
			return err
		}
	}

	pt, err := transport.NewTransport(clientTLSInfo)
	if err != nil {
		return err
	}

	// TODO(jonboulle): update peerURLs dynamically (i.e. when updating
	// clientURLs) instead of just using the initial fixed list here
	peerURLs := cls.PeerURLs()
	uf := func() []string {
		cls, err := etcdserver.GetClusterFromPeers(peerURLs)
		if err != nil {
			log.Printf("proxy: %v", err)
			return []string{}
		}
		return cls.ClientURLs()
	}
	ph := proxy.NewHandler(pt, uf)
	ph = &cors.CORSHandler{
		Handler: ph,
		Info:    corsInfo,
	}

	if proxyFlag.String() == proxyFlagReadonly {
		ph = proxy.NewReadonlyHandler(ph)
	}
	lcurls, err := flags.URLsFromFlags(fs, "listen-client-urls", "bind-addr", clientTLSInfo)
	if err != nil {
		return err
	}
	// Start a proxy server goroutine for each listen address
	for _, u := range lcurls {
		l, err := transport.NewListener(u.Host, u.Scheme, clientTLSInfo)
		if err != nil {
			return err
		}

		host := u.Host
		go func() {
			log.Print("proxy: listening for client requests on ", host)
			log.Fatal(http.Serve(l, ph))
		}()
	}
	return nil
}

// startEtcd launches the etcd server and HTTP handlers for client/server communication.
func startEtcd() (<-chan struct{}, error) {
	apurls, err := flags.URLsFromFlags(fs, "initial-advertise-peer-urls", "addr", peerTLSInfo)
	if err != nil {
		return nil, err
	}
	cls, err := setupCluster(apurls)
	if err != nil {
		return nil, fmt.Errorf("error setting up initial cluster: %v", err)
	}

	if *dir == "" {
		*dir = fmt.Sprintf("%v.etcd", *name)
		log.Printf("no data-dir provided, using default data-dir ./%s", *dir)
	}
	if err := os.MkdirAll(*dir, privateDirMode); err != nil {
		return nil, fmt.Errorf("cannot create data directory: %v", err)
	}
	if err := fileutil.IsDirWriteable(*dir); err != nil {
		return nil, fmt.Errorf("cannot write to data directory: %v", err)
	}

	pt, err := transport.NewTimeoutTransport(peerTLSInfo, rafthttp.ConnReadTimeout, rafthttp.ConnWriteTimeout)
	if err != nil {
		return nil, err
	}

	acurls, err := flags.URLsFromFlags(fs, "advertise-client-urls", "addr", clientTLSInfo)
	if err != nil {
		return nil, err
	}

	lpurls, err := flags.URLsFromFlags(fs, "listen-peer-urls", "peer-bind-addr", peerTLSInfo)
	if err != nil {
		return nil, err
	}

	if !peerTLSInfo.Empty() {
		log.Printf("etcd: peerTLS: %s", peerTLSInfo)
	}
	plns := make([]net.Listener, 0)
	for _, u := range lpurls {
		var l net.Listener
		l, err = transport.NewTimeoutListener(u.Host, u.Scheme, peerTLSInfo, rafthttp.ConnReadTimeout, rafthttp.ConnWriteTimeout)
		if err != nil {
			return nil, err
		}

		urlStr := u.String()
		log.Print("etcd: listening for peers on ", urlStr)
		defer func() {
			if err != nil {
				l.Close()
				log.Print("etcd: stopping listening for peers on ", urlStr)
			}
		}()
		plns = append(plns, l)
	}

	lcurls, err := flags.URLsFromFlags(fs, "listen-client-urls", "bind-addr", clientTLSInfo)
	if err != nil {
		return nil, err
	}

	if !clientTLSInfo.Empty() {
		log.Printf("etcd: clientTLS: %s", clientTLSInfo)
	}
	clns := make([]net.Listener, 0)
	for _, u := range lcurls {
		var l net.Listener
		l, err = transport.NewListener(u.Host, u.Scheme, clientTLSInfo)
		if err != nil {
			return nil, err
		}

		urlStr := u.String()
		log.Print("etcd: listening for client requests on ", urlStr)
		defer func() {
			if err != nil {
				l.Close()
				log.Print("etcd: stopping listening for client requests on ", urlStr)
			}
		}()
		clns = append(clns, l)
	}

	cfg := &etcdserver.ServerConfig{
		Name:            *name,
		ClientURLs:      acurls,
		PeerURLs:        apurls,
		DataDir:         *dir,
		SnapCount:       *snapCount,
		MaxSnapFiles:    *maxSnapFiles,
		MaxWALFiles:     *maxWalFiles,
		Cluster:         cls,
		DiscoveryURL:    *durl,
		DiscoveryProxy:  *dproxy,
		NewCluster:      clusterStateFlag.String() == clusterStateFlagNew,
		ForceNewCluster: *forceNewCluster,
		Transport:       pt,
//.........这里部分代码省略.........