DEVX-29: fix: use DOCKER_HOST env var in is_docker_ready + scan all rootless sockets

src/devx/molecule/start_docker.py

@@ -17,6 +17,7 @@ Usage::
 
 from __future__ import annotations
 
+import glob
 import os
 import subprocess  # nosec B404
 import sys
@@ -35,11 +36,12 @@ ROOTLESS_SOCK = f"/run/user/{os.getuid()}/docker.sock"
 
 def is_docker_ready() -> bool:
     """Check if Docker daemon is responding on the configured socket."""
+    docker_host = os.environ.get("DOCKER_HOST", f"unix://{DOCKER_SOCK}")
     result = subprocess.run(  # nosec B603 B607
         ["docker", "info"],
         capture_output=True,
         check=False,
-        env={**os.environ, "DOCKER_HOST": f"unix://{DOCKER_SOCK}"},
+        env={**os.environ, "DOCKER_HOST": docker_host},
     )
     return result.returncode == 0
 
@@ -123,8 +125,21 @@ def start_docker_daemon(timeout: int = DEFAULT_TIMEOUT) -> bool:
         click.echo(_("Docker daemon already running"))
         return True
 
+    # Scan for any rootless sockets at other UIDs
+    for sock in sorted(glob.glob("/run/user/*/docker.sock")):
+        if sock == ROOTLESS_SOCK:
+            continue
+        click.echo(f"Trying alternative rootless socket: {sock}")
+        os.environ["DOCKER_HOST"] = f"unix://{sock}"
+        if is_docker_ready():
+            click.echo(_("Docker daemon already running"))
+            return True
+
     click.echo(_("Host Docker not available, starting local dockerd..."))
 
+    # Reset DOCKER_HOST to host socket for local dockerd
+    os.environ["DOCKER_HOST"] = f"unix://{DOCKER_SOCK}"
+
     # Start local dockerd (requires privileged container)
     log_file = tempfile.NamedTemporaryFile(  # noqa: SIM115
         mode="w", suffix="dockerd.log", delete=False