From 6458766042a9a7d816c3a5df2bff3b8db4d593c2 Mon Sep 17 00:00:00 2001
From: Andrew Roberts <adroberts@gmail.com>
Date: Sun, 17 May 2026 22:10:51 -0400
Subject: [PATCH] fix: support ssh:// DOCKER_HOST via connhelper
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The Docker Go SDK alone cannot dial ssh:// transports — that requires github.com/docker/cli/cli/connhelper, which the docker CLI wires up but cdebug was missing. Without it, DOCKER_HOST=ssh://user@host fails with `dial tcp: lookup user@host: no such host`. This resolves the effective host from opts.Host or DOCKER_HOST, runs it through connhelper.GetConnectionHelper, and wires up the SSH dialer when present.
---
 pkg/docker/client.go | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/pkg/docker/client.go b/pkg/docker/client.go
index 52445a6e..45bf0f2e 100644
--- a/pkg/docker/client.go
+++ b/pkg/docker/client.go
@@ -4,7 +4,10 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"net/http"
+	"os"
 
+	"github.com/docker/cli/cli/connhelper"
 	"github.com/docker/cli/cli/streams"
 	"github.com/docker/docker/api/types/image"
 	"github.com/docker/docker/client"
@@ -28,8 +31,28 @@ func NewClient(opts Options) (*Client, error) {
 		client.FromEnv,
 		client.WithAPIVersionNegotiation(),
 	}
-	if len(opts.Host) > 0 {
-		dockerOpts = append(dockerOpts, client.WithHost(opts.Host))
+
+	host := opts.Host
+	if host == "" {
+		host = os.Getenv("DOCKER_HOST")
+	}
+	if host != "" {
+		helper, err := connhelper.GetConnectionHelper(host)
+		if err != nil {
+			return nil, fmt.Errorf("cannot resolve Docker connection helper: %w", err)
+		}
+		if helper != nil {
+			httpClient := &http.Client{
+				Transport: &http.Transport{DialContext: helper.Dialer},
+			}
+			dockerOpts = append(dockerOpts,
+				client.WithHTTPClient(httpClient),
+				client.WithHost(helper.Host),
+				client.WithDialContext(helper.Dialer),
+			)
+		} else if opts.Host != "" {
+			dockerOpts = append(dockerOpts, client.WithHost(opts.Host))
+		}
 	}
 
 	inner, err := client.NewClientWithOpts(dockerOpts...)