Golang cli.Context类代码示例

// removeDirCommandFunc executes the "rmdir" command.
func removeDirCommandFunc(c *cli.Context, client *etcd.Client) (*etcd.Response, error) {
	if len(c.Args()) == 0 {
		return nil, errors.New("Key required")
	}
	key := c.Args()[0]

	return client.DeleteDir(key)
}

// lsCommandFunc executes the "ls" command.
func lsCommandFunc(c *cli.Context, client *etcd.Client) (*etcd.Response, error) {
	key := "/"
	if len(c.Args()) != 0 {
		key = c.Args()[0]
	}
	recursive := c.Bool("recursive")

	// Retrieve the value from the server.
	return client.Get(key, false, recursive)
}

// Just like handlePrint but also passed the context of the command
func handleContextualPrint(c *cli.Context, fn handlerFunc, pFn contextualPrintFunc) {
	resp, err := rawhandle(c, fn)

	if err != nil {
		handleError(ErrorFromEtcd, err)
	}

	if resp != nil && pFn != nil {
		pFn(c, resp, c.GlobalString("output"))
	}
}

// handlePrint wraps the command function handlers to parse global flags
// into a client and to properly format the response objects.
func handlePrint(c *cli.Context, fn handlerFunc, pFn printFunc) {
	resp, err := rawhandle(c, fn)

	// Print error and exit, if necessary.
	if err != nil {
		handleError(ErrorFromEtcd, err)
	}

	if resp != nil && pFn != nil {
		pFn(resp, c.GlobalString("output"))
	}
}

// rPrint recursively prints out the nodes in the node structure.
func rPrint(c *cli.Context, n *etcd.Node) {

	if n.Dir && c.Bool("p") {
		fmt.Println(fmt.Sprintf("%v/", n.Key))
	} else {
		fmt.Println(n.Key)
	}

	for _, node := range n.Nodes {
		rPrint(c, &node)
	}
}

// rawhandle wraps the command function handlers and sets up the
// environment but performs no output formatting.
func rawhandle(c *cli.Context, fn handlerFunc) (*etcd.Response, error) {
	sync := !c.GlobalBool("no-sync")

	peerstr := c.GlobalString("peers")

	// Use an environment variable if nothing was supplied on the
	// command line
	if peerstr == "" {
		peerstr = os.Getenv("ETCDCTL_PEERS")
	}

	// If we still don't have peers, use a default
	if peerstr == "" {
		peerstr = "127.0.0.1:4001"
	}

	peers := strings.Split(peerstr, ",")

	// If no sync, create http path for each peer address
	if !sync {
		revisedPeers := make([]string, 0)
		for _, peer := range peers {
			if revisedPeer, err := createHttpPath(peer); err != nil {
				fmt.Fprintf(os.Stderr, "Unsupported url %v: %v\n", peer, err)
			} else {
				revisedPeers = append(revisedPeers, revisedPeer)
			}
		}
		peers = revisedPeers
	}

	client := etcd.NewClient(peers)

	if c.GlobalBool("debug") {
		go dumpCURL(client)
	}

	// Sync cluster.
	if sync {
		if ok := client.SyncCluster(); !ok {
			handleError(FailedToConnectToHost, errors.New("Cannot sync with the cluster using peers "+strings.Join(peers, ", ")))
		}
	}

	if c.GlobalBool("debug") {
		fmt.Fprintf(os.Stderr, "Cluster-Peers: %s\n",
			strings.Join(client.GetCluster(), " "))
	}

	// Execute handler function.
	return fn(c, client)
}

// updateCommandFunc executes the "update" command.
func updateCommandFunc(c *cli.Context, client *etcd.Client) (*etcd.Response, error) {
	if len(c.Args()) == 0 {
		return nil, errors.New("Key required")
	}
	key := c.Args()[0]
	value, err := argOrStdin(c.Args(), os.Stdin, 1)
	if err != nil {
		return nil, errors.New("Value required")
	}

	ttl := c.Int("ttl")

	return client.Update(key, value, uint64(ttl))
}

// setDirCommandFunc executes the "setDir" command.
func setDirCommandFunc(c *cli.Context, client *etcd.Client) (*etcd.Response, error) {
	if len(c.Args()) == 0 {
		return nil, errors.New("Key required")
	}
	key := c.Args()[0]
	ttl := c.Int("ttl")

	return client.SetDir(key, uint64(ttl))
}

// getCommandFunc executes the "get" command.
func getCommandFunc(c *cli.Context, client *etcd.Client) (*etcd.Response, error) {
	if len(c.Args()) == 0 {
		return nil, errors.New("Key required")
	}
	key := c.Args()[0]
	consistent := c.Bool("consistent")
	sorted := c.Bool("sort")

	// Setup consistency on the client.
	if consistent {
		client.SetConsistency(etcd.STRONG_CONSISTENCY)
	} else {
		client.SetConsistency(etcd.WEAK_CONSISTENCY)
	}

	// Retrieve the value from the server.
	return client.Get(key, sorted, false)
}

// setCommandFunc executes the "set" command.
func setCommandFunc(c *cli.Context, client *etcd.Client) (*etcd.Response, error) {
	if len(c.Args()) == 0 {
		return nil, errors.New("Key required")
	}
	key := c.Args()[0]
	value, err := argOrStdin(c.Args(), os.Stdin, 1)
	if err != nil {
		return nil, errors.New("Value required")
	}

	ttl := c.Int("ttl")
	prevValue := c.String("swap-with-value")
	prevIndex := c.Int("swap-with-index")

	if prevValue == "" && prevIndex == 0 {
		return client.Set(key, value, uint64(ttl))
	} else {
		return client.CompareAndSwap(key, value, uint64(ttl), prevValue, uint64(prevIndex))
	}
}

// execWatchCommandFunc executes the "exec-watch" command.
func execWatchCommandFunc(c *cli.Context, client *etcd.Client) (*etcd.Response, error) {
	_ = io.Copy
	_ = exec.Command
	args := c.Args()
	argsLen := len(args)

	if argsLen < 2 {
		return nil, errors.New("Key and command to exec required")
	}

	key := args[argsLen-1]
	cmdArgs := args[:argsLen-1]

	index := 0
	if c.Int("after-index") != 0 {
		index = c.Int("after-index") + 1
		key = args[0]
		cmdArgs = args[2:]
	}

	recursive := c.Bool("recursive")
	if recursive != false {
		key = args[0]
		cmdArgs = args[2:]
	}

	sigch := make(chan os.Signal, 1)
	signal.Notify(sigch, os.Interrupt)
	stop := make(chan bool)

	go func() {
		<-sigch
		stop <- true
		os.Exit(0)
	}()

	receiver := make(chan *etcd.Response)
	client.SetConsistency(etcd.WEAK_CONSISTENCY)
	go client.Watch(key, uint64(index), recursive, receiver, stop)

	for {
		resp := <-receiver
		cmd := exec.Command(cmdArgs[0], cmdArgs[1:]...)
		cmd.Env = environResponse(resp, os.Environ())

		stdout, err := cmd.StdoutPipe()
		if err != nil {
			fmt.Fprintf(os.Stderr, err.Error())
			os.Exit(1)
		}
		stderr, err := cmd.StderrPipe()
		if err != nil {
			fmt.Fprintf(os.Stderr, err.Error())
			os.Exit(1)
		}
		err = cmd.Start()
		if err != nil {
			fmt.Fprintf(os.Stderr, err.Error())
			os.Exit(1)
		}
		go io.Copy(os.Stdout, stdout)
		go io.Copy(os.Stderr, stderr)
		cmd.Wait()
	}

	return nil, nil
}