fix(docker_remote.py): login to Dockerhub and pull image under the same context

The change adjusts RemoteDocker.pull_image method to log in to Docker hub
and pull an image under the same user context.

This prevents a scenario when the login is performed as a regular user, but the
image pull is executed under the root user context, leading to an unauthenticated
request from Docker hub perspective.

Fixes: #10399

Author: dimakr

sdcm/utils/docker_remote.py

@@ -157,10 +157,9 @@ def __str__(self):
     @cache
     def pull_image(node, image):
         # Login docker-hub before pull, in case node authentication is expired or not logged-in.
-        docker_hub_login(remoter=node.remoter)
-        prefix = "sudo" if node.is_docker else ""
-        node.remoter.run(
-            f'{prefix} docker pull {image}', verbose=True, retry=3)
+        docker_hub_login(remoter=node.remoter, use_sudo=node.is_docker)
+        remote_cmd = node.remoter.sudo if node.is_docker else node.remoter.run
+        remote_cmd(f"docker pull {image}", verbose=True, retry=3)
 
     def __enter__(self):
         return self

sdcm/utils/docker_utils.py

@@ -518,15 +518,22 @@ def get_docker_hub_credentials() -> dict:
     return KeyStore().get_docker_hub_credentials()
 
 
-def docker_hub_login(remoter: CommandRunner) -> None:
-    docker_info = remoter.run("docker info", ignore_status=True)
+def docker_hub_login(remoter: CommandRunner, use_sudo: bool = False) -> None:
+    """
+    Logs into Docker Hub (if not already logged in) using credentials from the KeyStore.
+
+    :param remoter: CommandRunner, command runner instance
+    :param use_sudo: bool, whether to use sudo for remote commands. Optional, defaults to False.
+    """
+    remote_cmd = remoter.sudo if use_sudo else remoter.run
+    docker_info = remote_cmd("docker info", ignore_status=True)
     if docker_info.failed:
         remoter.log.error("Can't get docker info, probably there is no running Docker daemon on the host")
         return
     if match := re.search(r"^\s+Username: (.+)$", docker_info.stdout, re.MULTILINE):
         remoter.log.debug("Docker daemon is already logged in as `%s'.", match.group(1))
         return
-    if "Podman Engine" in remoter.run("docker version", ignore_status=True).stdout:
+    if "Podman Engine" in remote_cmd("docker version", ignore_status=True).stdout:
         remoter.log.info("When Podman daemon is used we don't login")
         return
     if not os.environ.get('JENKINS_URL'):
@@ -537,5 +544,5 @@ def docker_hub_login(remoter: CommandRunner) -> None:
     with remote_file(remoter=remoter, remote_path=password_file) as fobj:
         fobj.write(docker_hub_creds["password"])
     remoter.log.debug("Login to Docker Hub as `%s'", docker_hub_creds["username"])
-    remoter.run(cmd=f"docker login --username {docker_hub_creds['username']} --password-stdin < '{password_file}'")
+    remote_cmd(f"docker login --username {docker_hub_creds['username']} --password-stdin < '{password_file}'")
     remoter.run(f"rm '{password_file}'")