Golang data.Empty函數代碼示例

func TestSendConn(t *testing.T) {
	a, b, err := USocketPair()
	if err != nil {
		t.Fatal(err)
	}
	defer a.Close()
	defer b.Close()
	go func() {
		conn, err := SendConn(a, data.Empty().Set("type", "connection").Bytes())
		if err != nil {
			t.Fatal(err)
		}
		if err := conn.Send(data.Empty().Set("foo", "bar").Bytes(), nil); err != nil {
			t.Fatal(err)
		}
		conn.CloseWrite()
	}()
	payload, conn, err := ReceiveConn(b)
	if err != nil {
		t.Fatal(err)
	}
	if val := data.Message(string(payload)).Get("type"); val == nil || val[0] != "connection" {
		t.Fatalf("%v != %v\n", val, "connection")
	}
	msg, _, err := conn.Receive()
	if err != nil {
		t.Fatal(err)
	}
	if val := data.Message(string(msg)).Get("foo"); val == nil || val[0] != "bar" {
		t.Fatalf("%v != %v\n", val, "bar")
	}
}

func CmdRender(args []string, stdout, stderr io.Writer, in beam.Receiver, out beam.Sender) {
	if len(args) != 2 {
		fmt.Fprintf(stderr, "Usage: %s FORMAT\n", args[0])
		out.Send(data.Empty().Set("status", "1").Bytes(), nil)
		return
	}
	txt := args[1]
	if !strings.HasSuffix(txt, "\n") {
		txt += "\n"
	}
	t := template.Must(template.New("render").Parse(txt))
	for {
		payload, attachment, err := in.Receive()
		if err != nil {
			return
		}
		msg, err := data.Decode(string(payload))
		if err != nil {
			fmt.Fprintf(stderr, "decode error: %v\n")
		}
		if err := t.Execute(stdout, msg); err != nil {
			fmt.Fprintf(stderr, "rendering error: %v\n", err)
			out.Send(data.Empty().Set("status", "1").Bytes(), nil)
			return
		}
		if err := out.Send(payload, attachment); err != nil {
			return
		}
	}
}

func CmdListen(args []string, stdout, stderr io.Writer, in beam.Receiver, out beam.Sender) {
	if len(args) != 2 {
		out.Send(data.Empty().Set("status", "1").Set("message", "wrong number of arguments").Bytes(), nil)
		return
	}
	u, err := url.Parse(args[1])
	if err != nil {
		out.Send(data.Empty().Set("status", "1").Set("message", err.Error()).Bytes(), nil)
		return
	}
	l, err := net.Listen(u.Scheme, u.Host)
	if err != nil {
		out.Send(data.Empty().Set("status", "1").Set("message", err.Error()).Bytes(), nil)
		return
	}
	for {
		conn, err := l.Accept()
		if err != nil {
			out.Send(data.Empty().Set("status", "1").Set("message", err.Error()).Bytes(), nil)
			return
		}
		f, err := connToFile(conn)
		if err != nil {
			conn.Close()
			continue
		}
		out.Send(data.Empty().Set("type", "socket").Set("remoteaddr", conn.RemoteAddr().String()).Bytes(), f)
	}
}

func CmdConnect(args []string, stdout, stderr io.Writer, in beam.Receiver, out beam.Sender) {
	if len(args) != 2 {
		out.Send(data.Empty().Set("status", "1").Set("message", "wrong number of arguments").Bytes(), nil)
		return
	}
	u, err := url.Parse(args[1])
	if err != nil {
		out.Send(data.Empty().Set("status", "1").Set("message", err.Error()).Bytes(), nil)
		return
	}
	var tasks sync.WaitGroup
	for {
		_, attachment, err := in.Receive()
		if err != nil {
			break
		}
		if attachment == nil {
			continue
		}
		Logf("connecting to %s/%s\n", u.Scheme, u.Host)
		conn, err := net.Dial(u.Scheme, u.Host)
		if err != nil {
			out.Send(data.Empty().Set("cmd", "msg", "connect error: "+err.Error()).Bytes(), nil)
			return
		}
		out.Send(data.Empty().Set("cmd", "msg", "connection established").Bytes(), nil)
		tasks.Add(1)
		go func(attachment *os.File, conn net.Conn) {
			defer tasks.Done()
			// even when successful, conn.File() returns a duplicate,
			// so we must close the original
			var iotasks sync.WaitGroup
			iotasks.Add(2)
			go func(attachment *os.File, conn net.Conn) {
				defer iotasks.Done()
				io.Copy(attachment, conn)
			}(attachment, conn)
			go func(attachment *os.File, conn net.Conn) {
				defer iotasks.Done()
				io.Copy(conn, attachment)
			}(attachment, conn)
			iotasks.Wait()
			conn.Close()
			attachment.Close()
		}(attachment, conn)
	}
	tasks.Wait()
}

func CmdBeamreceive(args []string, stdout, stderr io.Writer, in beam.Receiver, out beam.Sender) {
	if len(args) != 2 {
		if err := out.Send(data.Empty().Set("status", "1").Set("message", "wrong number of arguments").Bytes(), nil); err != nil {
			Fatal(err)
		}
		return
	}
	var connector func(string) (chan net.Conn, error)
	connector = listener
	connections, err := connector(args[1])
	if err != nil {
		out.Send(data.Empty().Set("status", "1").Set("message", err.Error()).Bytes(), nil)
		return
	}
	// Copy in to conn
	ReceiveFromConn(connections, out)
}

func (rcv *Receiver) Run() error {
	r := beam.NewRouter(nil)
	r.NewRoute().KeyExists("cmd").Handler(func(p []byte, f *os.File) error {
		// Use the attachment as a beam return channel
		peer, err := beam.FileConn(f)
		if err != nil {
			f.Close()
			return err
		}
		f.Close()
		defer peer.Close()
		msg := data.Message(p)
		cmd := msg.Get("cmd")
		job := rcv.Engine.Job(cmd[0], cmd[1:]...)
		// Decode env
		env, err := data.Decode(msg.GetOne("env"))
		if err != nil {
			return fmt.Errorf("error decoding 'env': %v", err)
		}
		job.Env().InitMultiMap(env)
		stdout, err := beam.SendRPipe(peer, data.Empty().Set("cmd", "log", "stdout").Bytes())
		if err != nil {
			return err
		}
		job.Stdout.Add(stdout)
		stderr, err := beam.SendRPipe(peer, data.Empty().Set("cmd", "log", "stderr").Bytes())
		if err != nil {
			return err
		}
		job.Stderr.Add(stderr)
		stdin, err := beam.SendWPipe(peer, data.Empty().Set("cmd", "log", "stdin").Bytes())
		if err != nil {
			return err
		}
		job.Stdin.Add(stdin)
		// ignore error because we pass the raw status
		job.Run()
		err = peer.Send(data.Empty().Set("cmd", "status", fmt.Sprintf("%d", job.status)).Bytes(), nil)
		if err != nil {
			return err
		}
		return nil
	})
	_, err := beam.Copy(r, rcv.peer)
	return err
}

func (s *Sender) Handle(job *Job) Status {
	cmd := append([]string{job.Name}, job.Args...)
	env := data.Encode(job.Env().MultiMap())
	msg := data.Empty().Set("cmd", cmd...).Set("env", env)
	peer, err := beam.SendConn(s, msg.Bytes())
	if err != nil {
		return job.Errorf("beamsend: %v", err)
	}
	defer peer.Close()
	var tasks sync.WaitGroup
	defer tasks.Wait()
	r := beam.NewRouter(nil)
	r.NewRoute().KeyStartsWith("cmd", "log", "stdout").HasAttachment().Handler(func(p []byte, stdout *os.File) error {
		tasks.Add(1)
		go func() {
			io.Copy(job.Stdout, stdout)
			stdout.Close()
			tasks.Done()
		}()
		return nil
	})
	r.NewRoute().KeyStartsWith("cmd", "log", "stderr").HasAttachment().Handler(func(p []byte, stderr *os.File) error {
		tasks.Add(1)
		go func() {
			io.Copy(job.Stderr, stderr)
			stderr.Close()
			tasks.Done()
		}()
		return nil
	})
	r.NewRoute().KeyStartsWith("cmd", "log", "stdin").HasAttachment().Handler(func(p []byte, stdin *os.File) error {
		go func() {
			io.Copy(stdin, job.Stdin)
			stdin.Close()
		}()
		return nil
	})
	var status int
	r.NewRoute().KeyStartsWith("cmd", "status").Handler(func(p []byte, f *os.File) error {
		cmd := data.Message(p).Get("cmd")
		if len(cmd) != 2 {
			return fmt.Errorf("usage: %s <0-127>", cmd[0])
		}
		s, err := strconv.ParseUint(cmd[1], 10, 8)
		if err != nil {
			return fmt.Errorf("usage: %s <0-127>", cmd[0])
		}
		status = int(s)
		return nil

	})
	if _, err := beam.Copy(r, peer); err != nil {
		return job.Errorf("%v", err)
	}
	return Status(status)
}

func executeRootScript(script []*dockerscript.Command) error {
	if len(rootPlugins) > 0 {
		// If there are root plugins, wrap the script inside them
		var (
			rootCmd *dockerscript.Command
			lastCmd *dockerscript.Command
		)
		for _, plugin := range rootPlugins {
			pluginCmd := &dockerscript.Command{
				Args: []string{plugin},
			}
			if rootCmd == nil {
				rootCmd = pluginCmd
			} else {
				lastCmd.Children = []*dockerscript.Command{pluginCmd}
			}
			lastCmd = pluginCmd
		}
		lastCmd.Children = script
		script = []*dockerscript.Command{rootCmd}
	}
	handlers, err := Handlers(introspect)
	if err != nil {
		return err
	}
	defer handlers.Close()
	var tasks sync.WaitGroup
	defer func() {
		Debugf("Waiting for introspection...\n")
		tasks.Wait()
		Debugf("DONE Waiting for introspection\n")
	}()
	if introspect != nil {
		tasks.Add(1)
		go func() {
			Debugf("starting introspection\n")
			defer Debugf("done with introspection\n")
			defer tasks.Done()
			introspect.Send(data.Empty().Set("cmd", "log", "stdout").Set("message", "introspection worked!").Bytes(), nil)
			Debugf("XXX starting reading introspection messages\n")
			r := beam.NewRouter(handlers)
			r.NewRoute().All().Handler(func(p []byte, a *os.File) error {
				Logf("[INTROSPECTION] %s\n", beam.MsgDesc(p, a))
				return handlers.Send(p, a)
			})
			n, err := beam.Copy(r, introspect)
			Debugf("XXX done reading %d introspection messages: %v\n", n, err)
		}()
	}
	if err := executeScript(handlers, script); err != nil {
		return err
	}
	return nil
}

func CmdOpenfile(args []string, stdout, stderr io.Writer, in beam.Receiver, out beam.Sender) {
	for _, name := range args {
		f, err := os.Open(name)
		if err != nil {
			continue
		}
		if err := out.Send(data.Empty().Set("path", name).Set("type", "file").Bytes(), f); err != nil {
			f.Close()
		}
	}
}

func CmdExec(args []string, stdout, stderr io.Writer, in beam.Receiver, out beam.Sender) {
	cmd := exec.Command(args[1], args[2:]...)
	cmd.Stdout = stdout
	cmd.Stderr = stderr
	//cmd.Stdin = os.Stdin
	local, remote, err := beam.SocketPair()
	if err != nil {
		fmt.Fprintf(stderr, "%v\n", err)
		return
	}
	child, err := beam.FileConn(local)
	if err != nil {
		local.Close()
		remote.Close()
		fmt.Fprintf(stderr, "%v\n", err)
		return
	}
	local.Close()
	cmd.ExtraFiles = append(cmd.ExtraFiles, remote)

	var tasks sync.WaitGroup
	tasks.Add(1)
	go func() {
		defer Debugf("done copying to child\n")
		defer tasks.Done()
		defer child.CloseWrite()
		beam.Copy(child, in)
	}()

	tasks.Add(1)
	go func() {
		defer Debugf("done copying from child %d\n")
		defer tasks.Done()
		r := beam.NewRouter(out)
		r.NewRoute().All().Handler(func(p []byte, a *os.File) error {
			return out.Send(data.Message(p).Set("pid", fmt.Sprintf("%d", cmd.Process.Pid)).Bytes(), a)
		})
		beam.Copy(r, child)
	}()
	execErr := cmd.Run()
	// We can close both ends of the socket without worrying about data stuck in the buffer,
	// because unix socket writes are fully synchronous.
	child.Close()
	tasks.Wait()
	var status string
	if execErr != nil {
		status = execErr.Error()
	} else {
		status = "ok"
	}
	out.Send(data.Empty().Set("status", status).Set("cmd", args...).Bytes(), nil)
}

func (rcv *Receiver) Run() error {
	r := beam.NewRouter(nil)
	r.NewRoute().KeyExists("cmd").Handler(func(p []byte, f *os.File) error {
		// Use the attachment as a beam return channel
		peer, err := beam.FileConn(f)
		if err != nil {
			f.Close()
			return err
		}
		cmd := data.Message(p).Get("cmd")
		job := rcv.Engine.Job(cmd[0], cmd[1:]...)
		stdout, err := beam.SendPipe(peer, data.Empty().Set("cmd", "log", "stdout").Bytes())
		if err != nil {
			return err
		}
		job.Stdout.Add(stdout)
		stderr, err := beam.SendPipe(peer, data.Empty().Set("cmd", "log", "stderr").Bytes())
		if err != nil {
			return err
		}
		job.Stderr.Add(stderr)
		stdin, err := beam.SendPipe(peer, data.Empty().Set("cmd", "log", "stdin").Bytes())
		if err != nil {
			return err
		}
		job.Stdin.Add(stdin)
		// ignore error because we pass the raw status
		job.Run()
		err = peer.Send(data.Empty().Set("cmd", "status", fmt.Sprintf("%d", job.status)).Bytes(), nil)
		if err != nil {
			return err
		}
		return nil
	})
	_, err := beam.Copy(r, rcv.peer)
	return err
}

//	1) Find a handler for the command (if no handler, fail)
//	2) Attach new in & out pair to the handler
//	3) [in the background] Copy handler output to our own output
//	4) [in the background] Run the handler
//	5) Recursively executeScript() all children commands and wait for them to complete
//	6) Wait for handler to return and (shortly afterwards) output copy to complete
//	7) Profit
func executeCommand(out beam.Sender, cmd *dockerscript.Command) error {
	if flX {
		fmt.Printf("+ %v\n", strings.Replace(strings.TrimRight(cmd.String(), "\n"), "\n", "\n+ ", -1))
	}
	Debugf("executeCommand(%s)\n", strings.Join(cmd.Args, " "))
	defer Debugf("executeCommand(%s) DONE\n", strings.Join(cmd.Args, " "))
	if len(cmd.Args) == 0 {
		return fmt.Errorf("empty command")
	}
	Debugf("[executeCommand] sending job '%s'\n", strings.Join(cmd.Args, " "))
	job, err := beam.SendConn(out, data.Empty().Set("cmd", cmd.Args...).Set("type", "job").Bytes())
	if err != nil {
		return fmt.Errorf("%v\n", err)
	}
	var tasks sync.WaitGroup
	tasks.Add(1)
	Debugf("[executeCommand] spawning background copy of the output of '%s'\n", strings.Join(cmd.Args, " "))
	go func() {
		if out != nil {
			Debugf("[executeCommand] background copy of the output of '%s'\n", strings.Join(cmd.Args, " "))
			n, err := beam.Copy(out, job)
			if err != nil {
				Fatalf("[executeCommand] [%s] error during background copy: %v\n", strings.Join(cmd.Args, " "), err)
			}
			Debugf("[executeCommand] background copy done of the output of '%s': copied %d messages\n", strings.Join(cmd.Args, " "), n)
		}
		tasks.Done()
	}()
	// depth-first execution of children commands
	// executeScript() blocks until all commands are completed
	Debugf("[executeCommand] recursively running children of '%s'\n", strings.Join(cmd.Args, " "))
	executeScript(job, cmd.Children)
	Debugf("[executeCommand] DONE recursively running children of '%s'\n", strings.Join(cmd.Args, " "))
	job.CloseWrite()
	Debugf("[executeCommand] closing the input of '%s' (all children are completed)\n", strings.Join(cmd.Args, " "))
	Debugf("[executeCommand] waiting for background copy of '%s' to complete...\n", strings.Join(cmd.Args, " "))
	tasks.Wait()
	Debugf("[executeCommand] background copy of '%s' complete! This means the job completed.\n", strings.Join(cmd.Args, " "))
	return nil
}

func CmdPrompt(args []string, stdout, stderr io.Writer, in beam.Receiver, out beam.Sender) {
	if len(args) < 2 {
		fmt.Fprintf(stderr, "usage: %s PROMPT...\n", args[0])
		return
	}
	if !term.IsTerminal(0) {
		fmt.Fprintf(stderr, "can't prompt: no tty available...\n")
		return
	}
	fmt.Printf("%s: ", strings.Join(args[1:], " "))
	oldState, _ := term.SaveState(0)
	term.DisableEcho(0, oldState)
	line, _, err := bufio.NewReader(os.Stdin).ReadLine()
	if err != nil {
		fmt.Fprintln(stderr, err.Error())
		return
	}
	val := string(line)
	fmt.Printf("\n")
	term.RestoreTerminal(0, oldState)
	out.Send(data.Empty().Set("fromcmd", args...).Set("value", val).Bytes(), nil)
}

func Handlers(sink beam.Sender) (*beam.UnixConn, error) {
	var tasks sync.WaitGroup
	pub, priv, err := beam.USocketPair()
	if err != nil {
		return nil, err
	}
	go func() {
		defer func() {
			Debugf("[handlers] closewrite() on endpoint\n")
			// FIXME: this is not yet necessary but will be once
			// there is synchronization over standard beam messages
			priv.CloseWrite()
			Debugf("[handlers] done closewrite() on endpoint\n")
		}()
		r := beam.NewRouter(sink)
		r.NewRoute().HasAttachment().KeyIncludes("type", "job").Handler(func(payload []byte, attachment *os.File) error {
			conn, err := beam.FileConn(attachment)
			if err != nil {
				attachment.Close()
				return err
			}
			// attachment.Close()
			tasks.Add(1)
			go func() {
				defer tasks.Done()
				defer func() {
					Debugf("[handlers] '%s' closewrite\n", payload)
					conn.CloseWrite()
					Debugf("[handlers] '%s' done closewrite\n", payload)
				}()
				cmd := data.Message(payload).Get("cmd")
				Debugf("[handlers] received %s\n", strings.Join(cmd, " "))
				if len(cmd) == 0 {
					return
				}
				handler := GetHandler(cmd[0])
				if handler == nil {
					return
				}
				stdout, err := beam.SendRPipe(conn, data.Empty().Set("cmd", "log", "stdout").Set("fromcmd", cmd...).Bytes())
				if err != nil {
					return
				}
				defer stdout.Close()
				stderr, err := beam.SendRPipe(conn, data.Empty().Set("cmd", "log", "stderr").Set("fromcmd", cmd...).Bytes())
				if err != nil {
					return
				}
				defer stderr.Close()
				Debugf("[handlers] calling %s\n", strings.Join(cmd, " "))
				handler(cmd, stdout, stderr, beam.Receiver(conn), beam.Sender(conn))
				Debugf("[handlers] returned: %s\n", strings.Join(cmd, " "))
			}()
			return nil
		})
		beam.Copy(r, priv)
		Debugf("[handlers] waiting for all tasks\n")
		tasks.Wait()
		Debugf("[handlers] all tasks returned\n")
	}()
	return pub, nil
}