Refactor registry credential extraction into shared helper

Extract duplicate logic for determining which registry matches an image
into a shared `get_registry_for_image()` method in `DockerConfig`. This
method is now used by both `DockerInterface._get_credentials()` and
`AddonBuild.get_docker_config_json()`.

Move `DOCKER_HUB` and `IMAGE_WITH_HOST` constants to `docker/const.py`
to avoid circular imports between manager.py and interface.py.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

supervisor/addons/build.py

@@ -22,7 +22,8 @@ from ..const import (
     SOCKET_DOCKER,
 )
 from ..coresys import CoreSys, CoreSysAttributes
-from ..docker.interface import DOCKER_HUB, IMAGE_WITH_HOST, MAP_ARCH
+from ..docker.const import DOCKER_HUB
+from ..docker.interface import MAP_ARCH
 from ..exceptions import ConfigurationFileError, HassioArchNotFound
 from ..utils.common import FileConfiguration, find_one_filetype
 from .validate import SCHEMA_BUILD_CONFIG
@@ -131,23 +132,12 @@ class AddonBuild(FileConfiguration, CoreSysAttributes):
 
         Returns a JSON string with registry credentials for the base image's registry,
         or None if no matching registry is configured.
-
         """
+        # Early return before accessing base_image to avoid unnecessary arch lookup
         if not self.sys_docker.config.registries:
             return None
 
-        base_image = self.base_image
-        registry = None
-
-        # Check if base image uses a custom registry
-        matcher = IMAGE_WITH_HOST.match(base_image)
-        if matcher:
-            if matcher.group(1) in self.sys_docker.config.registries:
-                registry = matcher.group(1)
-        # If no match, check for Docker Hub credentials
-        elif DOCKER_HUB in self.sys_docker.config.registries:
-            registry = DOCKER_HUB
-
+        registry = self.sys_docker.config.get_registry_for_image(self.base_image)
         if not registry:
             return None
 

supervisor/docker/const.py

@@ -15,6 +15,12 @@ from ..const import MACHINE_ID
 
 RE_RETRYING_DOWNLOAD_STATUS = re.compile(r"Retrying in \d+ seconds?")
 
+# Docker Hub registry identifier
+DOCKER_HUB = "hub.docker.com"
+
+# Regex to match images with a registry host (e.g., ghcr.io/org/image)
+IMAGE_WITH_HOST = re.compile(r"^((?:[a-z0-9]+(?:-[a-z0-9]+)*\.)+[a-z]{2,})\/.+")
+
 
 class Capabilities(StrEnum):
     """Linux Capabilities."""

supervisor/docker/interface.py

@@ -8,7 +8,6 @@ from collections.abc import Awaitable
 from contextlib import suppress
 from http import HTTPStatus
 import logging
-import re
 from time import time
 from typing import Any, cast
 from uuid import uuid4
@@ -46,16 +45,13 @@ from ..jobs.decorator import Job
 from ..jobs.job_group import JobGroup
 from ..resolution.const import ContextType, IssueType, SuggestionType
 from ..utils.sentry import async_capture_exception
-from .const import ContainerState, PullImageLayerStage, RestartPolicy
+from .const import DOCKER_HUB, ContainerState, PullImageLayerStage, RestartPolicy
 from .manager import CommandReturn, PullLogEntry
 from .monitor import DockerContainerStateEvent
 from .stats import DockerStats
 
 _LOGGER: logging.Logger = logging.getLogger(__name__)
 
-IMAGE_WITH_HOST = re.compile(r"^((?:[a-z0-9]+(?:-[a-z0-9]+)*\.)+[a-z]{2,})\/.+")
-DOCKER_HUB = "hub.docker.com"
-
 MAP_ARCH: dict[CpuArch | str, str] = {
     CpuArch.ARMV7: "linux/arm/v7",
     CpuArch.ARMHF: "linux/arm/v6",
@@ -180,25 +176,16 @@ class DockerInterface(JobGroup, ABC):
         return self.meta_config.get("Healthcheck")
 
     def _get_credentials(self, image: str) -> dict:
-        """Return a dictionay with credentials for docker login."""
-        registry = None
+        """Return a dictionary with credentials for docker login."""
         credentials = {}
-        matcher = IMAGE_WITH_HOST.match(image)
-
-        # Custom registry
-        if matcher:
-            if matcher.group(1) in self.sys_docker.config.registries:
-                registry = matcher.group(1)
-                credentials[ATTR_REGISTRY] = registry
-
-        # If no match assume "dockerhub" as registry
-        elif DOCKER_HUB in self.sys_docker.config.registries:
-            registry = DOCKER_HUB
+        registry = self.sys_docker.config.get_registry_for_image(image)
 
         if registry:
             stored = self.sys_docker.config.registries[registry]
             credentials[ATTR_USERNAME] = stored[ATTR_USERNAME]
             credentials[ATTR_PASSWORD] = stored[ATTR_PASSWORD]
+            if registry != DOCKER_HUB:
+                credentials[ATTR_REGISTRY] = registry
 
             _LOGGER.debug(
                 "Logging in to %s as %s",

supervisor/docker/manager.py

@@ -49,7 +49,7 @@ from ..exceptions import (
 )
 from ..utils.common import FileConfiguration
 from ..validate import SCHEMA_DOCKER_CONFIG
-from .const import LABEL_MANAGED
+from .const import DOCKER_HUB, IMAGE_WITH_HOST, LABEL_MANAGED
 from .monitor import DockerMonitor
 from .network import DockerNetwork
 
@@ -202,6 +202,27 @@ class DockerConfig(FileConfiguration):
         """Return credentials for docker registries."""
         return self._data.get(ATTR_REGISTRIES, {})
 
+    def get_registry_for_image(self, image: str) -> str | None:
+        """Return the registry name if credentials are available for the image.
+
+        Matches the image against configured registries and returns the registry
+        name if found, or None if no matching credentials are configured.
+        """
+        if not self.registries:
+            return None
+
+        # Check if image uses a custom registry (e.g., ghcr.io/org/image)
+        matcher = IMAGE_WITH_HOST.match(image)
+        if matcher:
+            registry = matcher.group(1)
+            if registry in self.registries:
+                return registry
+        # If no registry prefix, check for Docker Hub credentials
+        elif DOCKER_HUB in self.registries:
+            return DOCKER_HUB
+
+        return None
+
 
 class DockerAPI(CoreSysAttributes):
     """Docker Supervisor wrapper.

tests/addons/test_build.py

@@ -10,7 +10,7 @@ from awesomeversion import AwesomeVersion
 from supervisor.addons.addon import Addon
 from supervisor.addons.build import AddonBuild
 from supervisor.coresys import CoreSys
-from supervisor.docker.interface import DOCKER_HUB
+from supervisor.docker.const import DOCKER_HUB
 
 from tests.common import is_in_list
 

tests/docker/test_credentials.py

@@ -2,7 +2,8 @@
 
 # pylint: disable=protected-access
 from supervisor.coresys import CoreSys
-from supervisor.docker.interface import DOCKER_HUB, DockerInterface
+from supervisor.docker.const import DOCKER_HUB
+from supervisor.docker.interface import DockerInterface
 
 
 def test_no_credentials(coresys: CoreSys, test_docker_interface: DockerInterface):