From 175e4e50480f7b9efc3c852c20605687cbb7655a Mon Sep 17 00:00:00 2001
From: Sebastiaan van Stijn <github@gone.nl>
Date: Thu, 30 Oct 2025 11:36:29 +0100
Subject: [PATCH] client: Client.TaskLogs: close reader on context cancellation

Use a cancelReadCloser to automatically close the reader when the context
is cancelled. Consumers are still recommended to manually close the reader,
but the cancelReadCloser makes the Close idempotent.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
---
 client/task_logs.go                           | 28 ++++++-------------
 .../github.com/moby/moby/client/task_logs.go  | 28 ++++++-------------
 2 files changed, 18 insertions(+), 38 deletions(-)

diff --git a/client/task_logs.go b/client/task_logs.go
index a4278b1f06..e4de019f30 100644
--- a/client/task_logs.go
+++ b/client/task_logs.go
@@ -27,9 +27,14 @@ type TaskLogsResult interface {
 	io.ReadCloser
 }
 
-// TaskLogs returns the logs generated by a task.
-// It's up to the caller to close the stream.
+// TaskLogs returns the logs generated by a service in a [TaskLogsResult].
+// as an [io.ReadCloser]. Callers should close the stream.
+//
+// The underlying [io.ReadCloser] is automatically closed if the context is canceled,
 func (cli *Client) TaskLogs(ctx context.Context, taskID string, options TaskLogsOptions) (TaskLogsResult, error) {
+	// TODO(thaJeztah): this function needs documentation about the format of ths stream (similar to for container logs)
+	// TODO(thaJeztah): migrate CLI utilities to the client where suitable; https://github.com/docker/cli/blob/v29.0.0-rc.1/cli/command/service/logs.go#L73-L348
+
 	query := url.Values{}
 	if options.ShowStdout {
 		query.Set("stdout", "1")
@@ -65,30 +70,15 @@ func (cli *Client) TaskLogs(ctx context.Context, taskID string, options TaskLogs
 		return nil, err
 	}
 	return &taskLogsResult{
-		body: resp.Body,
+		ReadCloser: newCancelReadCloser(ctx, resp.Body),
 	}, nil
 }
 
 type taskLogsResult struct {
-	// body must be closed to avoid a resource leak
-	body io.ReadCloser
+	io.ReadCloser
 }
 
 var (
 	_ io.ReadCloser       = (*taskLogsResult)(nil)
 	_ ContainerLogsResult = (*taskLogsResult)(nil)
 )
-
-func (r *taskLogsResult) Read(p []byte) (int, error) {
-	if r == nil || r.body == nil {
-		return 0, io.EOF
-	}
-	return r.body.Read(p)
-}
-
-func (r *taskLogsResult) Close() error {
-	if r == nil || r.body == nil {
-		return nil
-	}
-	return r.body.Close()
-}
diff --git a/vendor/github.com/moby/moby/client/task_logs.go b/vendor/github.com/moby/moby/client/task_logs.go
index a4278b1f06..e4de019f30 100644
--- a/vendor/github.com/moby/moby/client/task_logs.go
+++ b/vendor/github.com/moby/moby/client/task_logs.go
@@ -27,9 +27,14 @@ type TaskLogsResult interface {
 	io.ReadCloser
 }
 
-// TaskLogs returns the logs generated by a task.
-// It's up to the caller to close the stream.
+// TaskLogs returns the logs generated by a service in a [TaskLogsResult].
+// as an [io.ReadCloser]. Callers should close the stream.
+//
+// The underlying [io.ReadCloser] is automatically closed if the context is canceled,
 func (cli *Client) TaskLogs(ctx context.Context, taskID string, options TaskLogsOptions) (TaskLogsResult, error) {
+	// TODO(thaJeztah): this function needs documentation about the format of ths stream (similar to for container logs)
+	// TODO(thaJeztah): migrate CLI utilities to the client where suitable; https://github.com/docker/cli/blob/v29.0.0-rc.1/cli/command/service/logs.go#L73-L348
+
 	query := url.Values{}
 	if options.ShowStdout {
 		query.Set("stdout", "1")
@@ -65,30 +70,15 @@ func (cli *Client) TaskLogs(ctx context.Context, taskID string, options TaskLogs
 		return nil, err
 	}
 	return &taskLogsResult{
-		body: resp.Body,
+		ReadCloser: newCancelReadCloser(ctx, resp.Body),
 	}, nil
 }
 
 type taskLogsResult struct {
-	// body must be closed to avoid a resource leak
-	body io.ReadCloser
+	io.ReadCloser
 }
 
 var (
 	_ io.ReadCloser       = (*taskLogsResult)(nil)
 	_ ContainerLogsResult = (*taskLogsResult)(nil)
 )
-
-func (r *taskLogsResult) Read(p []byte) (int, error) {
-	if r == nil || r.body == nil {
-		return 0, io.EOF
-	}
-	return r.body.Read(p)
-}
-
-func (r *taskLogsResult) Close() error {
-	if r == nil || r.body == nil {
-		return nil
-	}
-	return r.body.Close()
-}