distinguish stdout and stderr in up logs

Signed-off-by: Nicolas De Loof <nicolas.deloof@gmail.com>

cmd/compose/logs.go

@@ -67,7 +67,7 @@ func runLogs(ctx context.Context, backend api.Service, opts logsOptions, service
 	if err != nil {
 		return err
 	}
-	consumer := formatter.NewLogConsumer(ctx, os.Stdout, !opts.noColor, !opts.noPrefix)
+	consumer := formatter.NewLogConsumer(ctx, os.Stdout, os.Stderr, !opts.noColor, !opts.noPrefix)
 	return backend.Logs(ctx, name, consumer, api.LogOptions{
 		Project:    project,
 		Services:   services,

cmd/compose/up.go

@@ -176,7 +176,7 @@ func runUp(ctx context.Context, backend api.Service, createOptions createOptions
 
 	var consumer api.LogConsumer
 	if !upOptions.Detach {
-		consumer = formatter.NewLogConsumer(ctx, os.Stdout, !upOptions.noColor, !upOptions.noPrefix)
+		consumer = formatter.NewLogConsumer(ctx, os.Stdout, os.Stderr, !upOptions.noColor, !upOptions.noPrefix)
 	}
 
 	attachTo := services

cmd/formatter/logs.go

@@ -32,18 +32,20 @@ type logConsumer struct {
 	ctx        context.Context
 	presenters sync.Map // map[string]*presenter
 	width      int
-	writer     io.Writer
+	stdout     io.Writer
+	stderr     io.Writer
 	color      bool
 	prefix     bool
 }
 
 // NewLogConsumer creates a new LogConsumer
-func NewLogConsumer(ctx context.Context, w io.Writer, color bool, prefix bool) api.LogConsumer {
+func NewLogConsumer(ctx context.Context, stdout, stderr io.Writer, color bool, prefix bool) api.LogConsumer {
 	return &logConsumer{
 		ctx:        ctx,
 		presenters: sync.Map{},
 		width:      0,
-		writer:     w,
+		stdout:     stdout,
+		stderr:     stderr,
 		color:      color,
 		prefix:     prefix,
 	}
@@ -84,19 +86,28 @@ func (l *logConsumer) getPresenter(container string) *presenter {
 
 // Log formats a log message as received from name/container
 func (l *logConsumer) Log(container, service, message string) {
+	l.write(l.stdout, container, service, message)
+}
+
+// Log formats a log message as received from name/container
+func (l *logConsumer) Err(container, service, message string) {
+	l.write(l.stderr, container, service, message)
+}
+
+func (l *logConsumer) write(w io.Writer, container, service, message string) {
 	if l.ctx.Err() != nil {
 		return
 	}
 	p := l.getPresenter(container)
 	for _, line := range strings.Split(message, "\n") {
-		fmt.Fprintf(l.writer, "%s%s\n", p.prefix, line)
+		fmt.Fprintf(w, "%s%s\n", p.prefix, line)
 	}
 }
 
 func (l *logConsumer) Status(container, msg string) {
 	p := l.getPresenter(container)
 	s := p.colors(fmt.Sprintf("%s %s\n", container, msg))
-	l.writer.Write([]byte(s)) //nolint:errcheck
+	l.stdout.Write([]byte(s)) //nolint:errcheck
 }
 
 func (l *logConsumer) computeWidth() {

pkg/api/api.go

@@ -438,6 +438,7 @@ type Stack struct {
 // LogConsumer is a callback to process log messages from services
 type LogConsumer interface {
 	Log(containerName, service, message string)
+	Err(containerName, service, message string)
 	Status(container, msg string)
 	Register(container string)
 }
@@ -461,8 +462,10 @@ type ContainerEvent struct {
 }
 
 const (
-	// ContainerEventLog is a ContainerEvent of type log. Line is set
+	// ContainerEventLog is a ContainerEvent of type log on stdout. Line is set
 	ContainerEventLog = iota
+	// ContainerEventErr is a ContainerEvent of type log on stderr. Line is set
+	ContainerEventErr = iota
 	// ContainerEventAttach is a ContainerEvent of type attach. First event sent about a container
 	ContainerEventAttach
 	// ContainerEventStopped is a ContainerEvent of type stopped.

pkg/compose/attach.go

@@ -69,21 +69,29 @@ func (s *composeService) attachContainer(ctx context.Context, container moby.Con
 		Service:   serviceName,
 	})
 
-	w := utils.GetWriter(func(line string) {
+	wOut := utils.GetWriter(func(line string) {
 		listener(api.ContainerEvent{
 			Type:      api.ContainerEventLog,
 			Container: containerName,
 			Service:   serviceName,
 			Line:      line,
 		})
 	})
+	wErr := utils.GetWriter(func(line string) {
+		listener(api.ContainerEvent{
+			Type:      api.ContainerEventErr,
+			Container: containerName,
+			Service:   serviceName,
+			Line:      line,
+		})
+	})
 
 	inspect, err := s.dockerCli.Client().ContainerInspect(ctx, container.ID)
 	if err != nil {
 		return err
 	}
 
-	_, _, err = s.attachContainerStreams(ctx, container.ID, inspect.Config.Tty, nil, w, w)
+	_, _, err = s.attachContainerStreams(ctx, container.ID, inspect.Config.Tty, nil, wOut, wErr)
 	return err
 }
 

pkg/compose/logs_test.go

@@ -193,6 +193,10 @@ func (l *testLogConsumer) Log(containerName, service, message string) {
 	l.logs[service][containerName] = append(l.logs[service][containerName], message)
 }
 
+func (l *testLogConsumer) Err(containerName, service, message string) {
+	l.Log(containerName, service, message)
+}
+
 func (l *testLogConsumer) Status(containerName, msg string) {}
 
 func (l *testLogConsumer) Register(containerName string) {}

pkg/compose/printer.go

@@ -120,6 +120,10 @@ func (p *printer) Run(ctx context.Context, cascadeStop bool, exitCodeFrom string
 				if !aborting {
 					p.consumer.Log(container, event.Service, event.Line)
 				}
+			case api.ContainerEventErr:
+				if !aborting {
+					p.consumer.Err(container, event.Service, event.Line)
+				}
 			}
 		}
 	}

pkg/e2e/compose_up_test.go

@@ -66,3 +66,13 @@ func TestPortRange(t *testing.T) {
 
 	c.RunDockerComposeCmd(t, "--project-name", projectName, "down", "--remove-orphans")
 }
+
+func TestStdoutStderr(t *testing.T) {
+	c := NewParallelCLI(t)
+	const projectName = "e2e-stdout-stderr"
+
+	res := c.RunDockerComposeCmdNoCheck(t, "-f", "fixtures/stdout-stderr/compose.yaml", "--project-name", projectName, "up")
+	res.Assert(t, icmd.Expected{Out: "log to stdout", Err: "log to stderr"})
+
+	c.RunDockerComposeCmd(t, "--project-name", projectName, "down", "--remove-orphans")
+}

pkg/e2e/fixtures/stdout-stderr/compose.yaml

@@ -0,0 +1,6 @@
+services:
+  stderr:
+    image: alpine
+    command: /bin/ash /log_to_stderr.sh
+    volumes:
+           - ./log_to_stderr.sh:/log_to_stderr.sh

pkg/e2e/fixtures/stdout-stderr/log_to_stderr.sh

@@ -0,0 +1,2 @@
+>&2 echo "log to stderr"
+echo "log to stdout"