Function RunMonitor

monitor/monitor.go:124–280

RunMonitor provides an interactive session for running and managing containers via specified IO.

(ctx context.Context, invokeConfig *build.InvokeConfig, rCtx *build.ResultHandle, stdin io.ReadCloser, stdout, stderr io.WriteCloser, progress *progress.Printer)

// RunMonitor provides an interactive session for running and managing containers via specified IO.
func RunMonitor(ctx context.Context, invokeConfig *build.InvokeConfig, rCtx *build.ResultHandle, stdin io.ReadCloser, stdout, stderr io.WriteCloser, progress *progress.Printer) error {
	progress.Pause()
	defer progress.Resume()

	defer stdin.Close()

	monitorIn, monitorOut := ioset.Pipe()
	defer func() {
		monitorIn.Close()
	}()
	monitorEnableCh := make(chan struct{})
	monitorDisableCh := make(chan struct{})
	monitorOutCtx := ioset.MuxOut{
		Out:         monitorOut,
		EnableHook:  func() { monitorEnableCh <- struct{}{} },
		DisableHook: func() { monitorDisableCh <- struct{}{} },
	}

	containerIn, containerOut := ioset.Pipe()
	defer func() {
		containerIn.Close()
	}()
	containerOutCtx := ioset.MuxOut{
		Out: containerOut,
		// send newline to hopefully get the prompt; TODO: better UI (e.g. reprinting the last line)
		EnableHook:  func() { containerOut.Stdin.Write([]byte("\n")) },
		DisableHook: func() {},
	}

	invokeForwarder := ioset.NewForwarder()
	invokeForwarder.SetIn(&containerIn)
	m := &monitor{
		rCtx:      rCtx,
		processes: processes.NewManager(),
		invokeIO:  invokeForwarder,
		muxIO: ioset.NewMuxIO(ioset.In{
			Stdin:  io.NopCloser(stdin),
			Stdout: nopCloser{stdout},
			Stderr: nopCloser{stderr},
		}, []ioset.MuxOut{monitorOutCtx, containerOutCtx}, 1, func(prev int, res int) string {
			if prev == 0 && res == 0 {
				// No toggle happened because container I/O isn't enabled.
				return "Process isn't attached (previous \"exec\" exited?). Use \"attach\" for attaching or \"rollback\" or \"exec\" for running new one.\n"
			}
			return "Switched IO\n"
		}),
	}
	m.ctx, m.cancel = context.WithCancelCause(context.Background())

	defer func() {
		if err := m.Close(); err != nil {
			logrus.Warnf("close error: %v", err)
		}
	}()

	// Start container automatically
	fmt.Fprintf(stdout, "Launching interactive container. Press Ctrl-a-c to switch to monitor console\n")
	invokeConfig.Rollback = false