Golang flag.Lookup函数代码示例

//####################################//
// Code
//====================================//
// Init code
func init() {
	// FIXME init flags
	const (
		flagDef_Debug = false
		flagDescDebug = "   -debug   enable debug"
		flagDef_Quiet = false
		flagDescQuiet = "-q -quiet   suppress output"
	)
	flag.BoolVar(&flagDebug, "debug", false, flagDescDebug)
	flag.BoolVar(&flagQuiet, "q", false, flagDescQuiet)
	flag.BoolVar(&flagQuiet, "quiet", false, flagDescQuiet)

	//----------------------------------//
	// Help
	// FIXME update help
	flag.Usage = func() {
		usage := `Usage: %s [options]
Options:
  ` + flag.Lookup("q").Usage + `
  ` + flag.Lookup("debug").Usage + `
  No more options for now.

MIT, BSD or something. There is no help.
`
		fmt.Fprintf(os.Stderr, usage, os.Args[0])
	}
	//----------------------------------//
}

func TestRegisterFlags(t *testing.T) {
	c := &Config{
		DHTRouters:    "example.router.com:6060",
		MaxNodes:      2020,
		CleanupPeriod: time.Second,
		SavePeriod:    time.Second * 2,
		RateLimit:     999,
	}
	RegisterFlags(c)
	if flag.Lookup("routers").DefValue != c.DHTRouters {
		t.Fatal("Incorrect routers flag")
	}
	if flag.Lookup("maxNodes").DefValue != strconv.FormatInt(int64(c.MaxNodes), 10) {
		t.Fatal("Incorrect maxNodes flag")
	}
	if flag.Lookup("cleanupPeriod").DefValue != c.CleanupPeriod.String() {
		t.Fatal("Incorrect cleanupPeriod flag")
	}
	if flag.Lookup("savePeriod").DefValue != c.SavePeriod.String() {
		t.Fatal("Incorrect routers flag")
	}
	if flag.Lookup("rateLimit").DefValue != strconv.FormatInt(c.RateLimit, 10) {
		t.Fatal("Incorrect routers flag")
	}
}

func main() {
	flag.Parse()

	if *cliVersion {
		fmt.Println(flag.Lookup("version").Usage)
		exit(0)
		return
	}
	if *cliHelp {
		fmt.Println(flag.Lookup("help").Usage)
		exit(0)
		return
	}
	var res beatsone.BeatsOne
	var err error
	if *cliSchedule {
		res, err = beatsone.GetSchedule()
	} else {
		res, err = beatsone.GetNowPlaying()
	}
	if err != nil {
		fmt.Println(err)
		exit(1)
	}
	if *cliJSON {
		fmt.Println(res.JSONString())
	} else {
		fmt.Println(res.String())
	}
	exit(0)
	return
}

func (p *GitParser) Setup() {
	executable := flag.Lookup("executable").Value.String()
	out := flag.Lookup("out").Value.String()

	if out == "<STDOUT>" {
		out = "REVISION.json"
	}

	hook := executable + " -out=\"" + out + "\"; # scm-status hook\r\n"

	hook_dir := strings.Join([]string{p.Dir(), ".git", "hooks"}, path_separator)

	filenames := []string{
		hook_dir + path_separator + "post-checkout",
		hook_dir + path_separator + "post-merge",
		hook_dir + path_separator + "post-commit",
	}

	for _, filename := range filenames {
		fp, _ := os.OpenFile(filename, os.O_RDWR+os.O_APPEND+os.O_CREATE, 0775)

		_, _ = fp.WriteString(hook)

		fp.Close()
	}
}

func main() {
	flag.Parse()

	if flagOne == "" {
		fmt.Fprintf(os.Stdout, "Usage of cody.guo ok %s:\n", os.Args[0])
		flag.PrintDefaults()
		os.Exit(1)
	}

	fmt.Println("参数数量:", flag.NFlag())
	oneFlag := flag.Lookup("one")

	fmt.Println(oneFlag.Name, oneFlag.Value)

	// fmt.Println(len(os.Args))

	if debug {
		fmt.Println("debug is on.")
	} else {
		fmt.Println("debug is off.")
	}

	fmt.Println(flagOne)

	debugFlag := flag.Lookup("d")
	fmt.Println(debugFlag.Name, debugFlag.Value)

}

func fakeRequest() {
	flag.Lookup("alsologtostderr").Value.Set("true")
	flag.Lookup("log_dir").Value.Set("./log_dir")
	flag.Parse()
	glog.Infoln("begin fake..")
	// test_uid := "45529"
	host := "0.0.0.0"
	port := "12231"
	dirver_trail_json := `[{"lat":"33.33066","lng":"121.284148","t":1472338663}]`
	driver_trail_form := url.Values{
		"session_id": []string{"test_uid"},
		"json":       []string{dirver_trail_json},
		"city":       []string{"上海"},
	}

	ticker := time.NewTicker(time.Second * 5)
	for t := range ticker.C {
		resp, err := http.PostForm(fmt.Sprintf("http://%s:%s/driver/trail", host, port), driver_trail_form)
		if err != nil {
			glog.Errorf("at %s, PostForm-err: %s\n", t, err)
		}
		defer resp.Body.Close()
		resp_body, err := ioutil.ReadAll(resp.Body)
		if err != nil {
			glog.Errorf("at %s, ioutil.ReadAll-err: %s\n", t, err)
		}
		glog.Infof("at %s, fake post, fadback is %s", t, string(resp_body))
	}
}

func main() {
	// Initialise our configuration from flags

	var nodeName = flag.String("name", REQUIRED, "Node network name and port, e.g. localhost:3000")
	var gobName = flag.String("gob", "", "Alternative gob network name and port for clients, allowing clients to connect over a different physical interface to nodes.")
	var httpName = flag.String("http", "", "Network name and port for the http ExpVar to listen on.")
	var cborName = flag.String("cbor", "", "Network name and port for the CBOR RPC interface to listen on.")
	var nodePath = flag.String("path", REQUIRED, "Node root path for configuration and log files")
	var clusterID = flag.String("id", "", "Cluster ID that this node is part of")

	flag.Parse()

	if flag.Lookup("help") != nil || flag.Lookup("h") != nil {
		flag.PrintDefaults()
		return
	}

	if *nodeName == REQUIRED {
		log.Printf("name missing.\n")
		flag.PrintDefaults()
		return
	}

	if *nodePath == REQUIRED {
		log.Printf("path missing.\n")
		flag.PrintDefaults()
		return
	}

	// Create our server
	serverNode, err := server.NewServerNode(*nodeName, *gobName, *httpName, *cborName, *nodePath, *clusterID)

	if err != nil {
		log.Fatalf("Unable to start server due to errors.\n")
	}

	expvar.Publish("node", expvar.Func(serverNode.ExpVar))

	//dataLog := &memlog.MemoryLog{}

	// Start a listener to handle incoming requests from other peers
	err = serverNode.ListenConnections()
	if err != nil {
		log.Fatalf("Error starting listener: %v\n", err)
	}

	// Setup signal handling to catch interrupts.
	sigc := make(chan os.Signal, 1)
	signal.Notify(sigc,
		os.Interrupt,
		os.Kill)
	go func() {
		<-sigc
		serverNode.RequestShutdown("Request to terminate process detected.")
	}()

	serverNode.WaitForShutdown()

}

func main() {
	settings.Init()
	flag.Parse()

	if len(os.Args) == 1 {
		flag.Usage()
		return
	}

	if flag.Lookup("run") == nil && flag.Lookup("svcctl") == nil && flag.Lookup("help") == nil && flag.Lookup("console") == nil {
		flag.Usage()
		return
	}

	if *help {
		flag.Usage()
		return
	}

	LogFile, err := os.OpenFile(settings.Log.File, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0777)
	if err != nil {
		fmt.Println(err)
		return
	}

	p := &Program{
		Logger: log.New(LogFile, "[filesync]", log.Ldefault|log.Lmicroseconds),
	}

	s, err := svc.New(p, &svc.Config{
		Name:        "Filesync",
		DisplayName: "FileSync Service",
		Description: "Filesync is a simple tool to sync files between multiple directory pairs.",
		Arguments:   []string{"-run"},
	})

	if err != nil {
		fmt.Println(err.Error())
		return
	}

	if *run {
		if *console {
			p.Logger = log.New(os.Stdout, "[filesync]", log.Ldefault|log.Lmicroseconds)
			p.run()
			return
		}
		err := s.Run()
		fmt.Println("run with error: ", err)
		return
	}

	Actions := strings.Split(*controls, ",")
	for _, action := range Actions {
		err := svc.Control(s, action)
		fmt.Println(err)
	}

}

func main() {
	flag.Parse()

	flagsOk := true
	if flag.Lookup("project").Value.String() == "" {
		fmt.Fprintf(os.Stderr, "Flag --project is required\n")
		flagsOk = false
	}

	var sourceFlagCount int
	if flag.Lookup("dataset").Value.String() != "" {
		sourceFlagCount++
	}
	if flag.Lookup("jobid").Value.String() != "" {
		sourceFlagCount++
	}
	if sourceFlagCount != 1 {
		fmt.Fprintf(os.Stderr, "Exactly one of --dataset or --jobid must be set\n")
		flagsOk = false
	}

	if !flagsOk {
		os.Exit(1)
	}

	tableRE, err := regexp.Compile(*table)
	if err != nil {
		fmt.Fprintf(os.Stderr, "--table is not a valid regular expression: %q\n", *table)
		os.Exit(1)
	}

	httpClient, err := google.DefaultClient(context.Background(), bigquery.Scope)
	if err != nil {
		log.Fatalf("Creating http client: %v", err)
	}

	client, err := bigquery.NewClient(httpClient, *project)
	if err != nil {
		log.Fatalf("Creating bigquery client: %v", err)
	}

	if *jobID != "" {
		printQueryResults(client, *jobID)
		return
	}
	ds := client.Dataset(*dataset)
	var tables []*bigquery.Table
	tables, err = ds.ListTables(context.Background())
	if err != nil {
		log.Fatalf("Listing tables: %v", err)
	}
	for _, t := range tables {
		if tableRE.MatchString(t.TableID) {
			printTable(client, t)
		}
	}
}

func main() {
	flag.Parse()

	flagsOk := true
	if flag.Lookup("project").Value.String() == "" {
		fmt.Fprintf(os.Stderr, "Flag --project is required\n")
		flagsOk = false
	}

	var sourceFlagCount int
	if flag.Lookup("dataset").Value.String() != "" {
		sourceFlagCount++
	}
	if flag.Lookup("jobid").Value.String() != "" {
		sourceFlagCount++
	}
	if sourceFlagCount != 1 {
		fmt.Fprintf(os.Stderr, "Exactly one of --dataset or --jobid must be set\n")
		flagsOk = false
	}

	if !flagsOk {
		os.Exit(1)
	}

	ctx := context.Background()
	tableRE, err := regexp.Compile(*table)
	if err != nil {
		fmt.Fprintf(os.Stderr, "--table is not a valid regular expression: %q\n", *table)
		os.Exit(1)
	}

	client, err := bigquery.NewClient(ctx, *project)
	if err != nil {
		log.Fatalf("Creating bigquery client: %v", err)
	}

	if *jobID != "" {
		printQueryResults(ctx, client, *jobID)
		return
	}
	ds := client.Dataset(*dataset)
	tableIter := ds.Tables(context.Background())
	for {
		t, err := tableIter.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			log.Fatalf("Listing tables: %v", err)
		}
		if tableRE.MatchString(t.TableID) {
			printTable(ctx, client, t)
		}
	}
}

func UpdateLoggingFlagsFromConfig(conf *Config) {
	err := flag.Lookup("v").Value.Set(strconv.Itoa(conf.Verbosity))
	if err != nil {
		glog.Errorf("Failed to apply config.Verbosity to flag.v: %v", err)
	}

	err = flag.Lookup("logtostderr").Value.Set("true")
	if err != nil {
		glog.Errorf("Failed to set flag.logtostderr to true: %v", err)
	}
}

func logFlush() {
	// go run main.go -alsologtostderr -log_dir="./"
	logDir := flag.Lookup("log_dir")
	testFlag := flag.Lookup("log_dir")
	glog.Infoln("lookup before parse", logDir.Name, logDir.Value, testFlag)
	err := flag.Set("log_dir", "test_value")
	glog.Errorln("err: ", err)
	glog.Infoln("abc..")
	glog.Infof("abc..%d", 123)
	logDir = flag.Lookup("log_dir")
	testFlag = flag.Lookup("log_dir")
	glog.Infoln("lookup before parse", logDir.Name, logDir.Value, testFlag.Name, testFlag.Value)
	glog.Flush()
}

func computeTriple() string {
	if *triple != "" {
		// Ensure os/arch aren't specified if triple/ is specified.
		//
		// This is an ugly way of telling whether or not -os or -arch were
		// specified. We can't just check the value, as it will have a default.
		archFlag := flag.Lookup("arch")
		osFlag := flag.Lookup("os")
		flag.Visit(func(f *flag.Flag) {
			switch f {
			case archFlag, osFlag:
				fmt.Fprintln(os.Stderr, tripleArchOsError)
				os.Exit(1)
			}
		})
		return *triple
	}

	// -arch is either an architecture name recognised by
	// the gc compiler, or an LLVM architecture name.
	targetArch := *arch
	if targetArch == "" {
		targetArch = runtime.GOARCH
	}
	switch targetArch {
	case "386":
		targetArch = "x86"
	case "amd64", "x86_64":
		targetArch = "x86-64"
	}

	// -os is either an OS name recognised by the gc
	// compiler, or an LLVM OS name.
	targetOS := *os_
	if targetOS == "" {
		targetOS = runtime.GOOS
	}
	switch targetOS {
	case "windows":
		targetOS = "win32"
	case "darwin":
		// Using darwin11 rather than just darwin enables TLS support,
		// making llgo-dist run without manually specifying a target
		// triple
		targetOS = "darwin11"
	}

	tripleArch := getTripleArchName(targetArch)
	return fmt.Sprintf("%s-unknown-%s", tripleArch, targetOS)
}

// Check returns a non-nil error if the Config is unusable.
func (c Config) Check() error {
	if c.SourceBuffer <= 2 {
		return errors.New("-source-buffer must be greater than 2")
	}
	if c.FrameBytes < 1 {
		return errors.New("-frame-bytes must not be zero")
	}
	if c.Path == "" {
		return errors.New("-path must not be empty")
	}
	if c.CPUMax < 0 {
		return errors.New("-cpu-max must not be negative")
	}
	if c.CPUMax == 0 {
		c.CPUMax = runtime.NumCPU()
	}
	if c.ExecFlag && c.Path != flag.Lookup("path").DefValue && c.Path != "" {
		return errors.New("cannot combine -exec and -path")
	}
	if c.ExecFlag == (len(c.Args) == 0) {
		return errors.New("cannot use -exec without providing a command (or vice versa)")
	}
	if _, ok := Filters[c.FrameFilter]; !ok {
		haveFilters := []string{}
		for f := range Filters {
			haveFilters = append(haveFilters, "\""+f+"\"")
		}
		return fmt.Errorf("-frame-filter \"%s\" not supported; try one of %v", c.FrameFilter, haveFilters)
	}
	return nil
}

func init() {
	// Override the default cAdvisor housekeeping interval.
	if f := flag.Lookup("housekeeping_interval"); f != nil {
		f.DefValue = defaultHousekeepingInterval.String()
		f.Value.Set(f.DefValue)
	}
}