attach: wait for exit code from ContainerWait

Such as with `docker run`, if a user CTRL-Cs while attached to a
container, we should forward the signal and wait for the exit from
`ContainerWait`, instead of just returning.

Signed-off-by: Laura Brehm <laurabrehm@hey.com>

Author: laurazard

cli/command/container/attach.go

@@ -72,7 +72,8 @@ func RunAttach(ctx context.Context, dockerCLI command.Cli, containerID string, o
 	apiClient := dockerCLI.Client()
 
 	// request channel to wait for client
-	resultC, errC := apiClient.ContainerWait(ctx, containerID, "")
+	waitCtx := context.WithoutCancel(ctx)
+	resultC, errC := apiClient.ContainerWait(waitCtx, containerID, "")
 
 	c, err := inspectContainerAndCheckState(ctx, apiClient, containerID)
 	if err != nil {
@@ -163,9 +164,6 @@ func getExitStatus(errC <-chan error, resultC <-chan container.WaitResponse) err
 			return cli.StatusError{StatusCode: int(result.StatusCode)}
 		}
 	case err := <-errC:
-		if errors.Is(err, context.Canceled) {
-			return nil
-		}
 		return err
 	}
 

cli/command/container/attach_test.go

@@ -119,8 +119,11 @@ func TestGetExitStatus(t *testing.T) {
 			expectedError: cli.StatusError{StatusCode: 15},
 		},
 		{
+			result: &container.WaitResponse{
+				StatusCode: 130,
+			},
 			err:           context.Canceled,
-			expectedError: nil,
+			expectedError: cli.StatusError{StatusCode: 130},
 		},
 	}
 

e2e/container/attach_test.go

@@ -48,6 +48,28 @@ func TestAttachInterrupt(t *testing.T) {
 	time.Sleep(500 * time.Millisecond)
 	c.Process.Signal(os.Interrupt)
 
+	_ = c.Wait()
+	assert.Equal(t, c.ProcessState.ExitCode(), 130)
+	assert.Equal(t, d.String(), "")
+}
+
+func TestAttachInterruptWithoutStdin(t *testing.T) {
+	result := icmd.RunCommand("docker", "run", "-dit", fixtures.AlpineImage, "sh", "-c", "sleep 5")
+	result.Assert(t, icmd.Success)
+	containerID := strings.TrimSpace(result.Stdout())
+
+	// run it as such so we can signal it later
+	c := exec.Command("docker", "attach", containerID)
+	d := bytes.Buffer{}
+	c.Stdout = &d
+	c.Stderr = &d
+	_, err := pty.Start(c)
+	assert.NilError(t, err)
+
+	// have to wait a bit to give time for the command to execute/print
+	time.Sleep(500 * time.Millisecond)
+	c.Process.Signal(os.Interrupt)
+
 	_ = c.Wait()
 	assert.Equal(t, c.ProcessState.ExitCode(), 0)
 	assert.Equal(t, d.String(), "")