attach: Use ContainerWait instead of Inspect

Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>

Author: mlaventure

cli/command/container/attach.go

@@ -66,6 +66,9 @@ func runAttach(dockerCli command.Cli, opts *attachOptions) error {
 	ctx := context.Background()
 	client := dockerCli.Client()
 
+	// request channel to wait for client
+	resultC, errC := client.ContainerWait(ctx, opts.container, "")
+
 	c, err := inspectContainerAndCheckState(ctx, client, opts.container)
 	if err != nil {
 		return err
@@ -140,7 +143,18 @@ func runAttach(dockerCli command.Cli, opts *attachOptions) error {
 	if errAttach != nil {
 		return errAttach
 	}
-	return getExitStatus(ctx, dockerCli.Client(), opts.container)
+
+	// get status code
+	select {
+	case result := <-resultC:
+		if result.StatusCode != 0 {
+			return cli.StatusError{StatusCode: int(result.StatusCode)}
+		}
+	case err := <-errC:
+		return err
+	}
+
+	return nil
 }
 
 func resizeTTY(ctx context.Context, dockerCli command.Cli, containerID string) {
@@ -157,19 +171,3 @@ func resizeTTY(ctx context.Context, dockerCli command.Cli, containerID string) {
 		logrus.Debugf("Error monitoring TTY size: %s", err)
 	}
 }
-
-func getExitStatus(ctx context.Context, apiclient client.ContainerAPIClient, containerID string) error {
-	container, err := apiclient.ContainerInspect(ctx, containerID)
-	if err != nil {
-		// If we can't connect, then the daemon probably died.
-		if !client.IsErrConnectionFailed(err) {
-			return err
-		}
-		return cli.StatusError{StatusCode: -1}
-	}
-	status := container.State.ExitCode
-	if status != 0 {
-		return cli.StatusError{StatusCode: status}
-	}
-	return nil
-}

cli/command/container/attach_test.go

@@ -4,13 +4,10 @@ import (
 	"io/ioutil"
 	"testing"
 
-	"github.com/docker/cli/cli"
 	"github.com/docker/cli/internal/test"
 	"github.com/docker/cli/internal/test/testutil"
 	"github.com/docker/docker/api/types"
 	"github.com/pkg/errors"
-	"github.com/stretchr/testify/assert"
-	"golang.org/x/net/context"
 )
 
 func TestNewAttachCommandErrors(t *testing.T) {
@@ -76,42 +73,3 @@ func TestNewAttachCommandErrors(t *testing.T) {
 		testutil.ErrorContains(t, cmd.Execute(), tc.expectedError)
 	}
 }
-
-func TestGetExitStatus(t *testing.T) {
-	containerID := "the exec id"
-	expecatedErr := errors.New("unexpected error")
-
-	testcases := []struct {
-		inspectError  error
-		exitCode      int
-		expectedError error
-	}{
-		{
-			inspectError: nil,
-			exitCode:     0,
-		},
-		{
-			inspectError:  expecatedErr,
-			expectedError: expecatedErr,
-		},
-		{
-			exitCode:      15,
-			expectedError: cli.StatusError{StatusCode: 15},
-		},
-	}
-
-	for _, testcase := range testcases {
-		client := &fakeClient{
-			inspectFunc: func(id string) (types.ContainerJSON, error) {
-				assert.Equal(t, containerID, id)
-				return types.ContainerJSON{
-					ContainerJSONBase: &types.ContainerJSONBase{
-						State: &types.ContainerState{ExitCode: testcase.exitCode},
-					},
-				}, testcase.inspectError
-			},
-		}
-		err := getExitStatus(context.Background(), client, containerID)
-		assert.Equal(t, testcase.expectedError, err)
-	}
-}

e2e/container/attach_test.go

@@ -0,0 +1,17 @@
+package container
+
+import (
+	"testing"
+
+	"github.com/gotestyourself/gotestyourself/icmd"
+)
+
+func TestAttachExitCode(t *testing.T) {
+	cName := "test-attach-exit-code"
+	icmd.RunCommand("docker", "run", "-d", "--rm", "--name", cName,
+		alpineImage, "sh", "-c", "sleep 5 ; exit 21").Assert(t, icmd.Success)
+	cmd := icmd.Command("docker", "wait", cName)
+	res := icmd.StartCmd(cmd)
+	icmd.RunCommand("docker", "attach", cName).Assert(t, icmd.Expected{ExitCode: 21})
+	icmd.WaitOnCmd(5, res).Assert(t, icmd.Success)
+}