Fix Supervisor logs fallback (#5022)

Supervisor logs fallback in get_supervisor_logs didn't work properly
because the exception was caught in api_process_raw instead. This was
not discovered in tests because the side effect raised OSError, which
isn't handled there.

To address that, I split the advanced_logs to two functions, one being a
wrapped API handler, one being plain function returning response without
any additional error handling. The tests now check for both cases of
errors (HassioError and random generic Python error).

Refs #5021

supervisor/api/__init__.py

@@ -401,7 +401,7 @@ class RestAPI(CoreSysAttributes):
 
         async def get_supervisor_logs(*args, **kwargs):
             try:
-                return await self._api_host.advanced_logs(
+                return await self._api_host.advanced_logs_handler(
                     *args, identifier="hassio_supervisor", **kwargs
                 )
             except Exception as err:  # pylint: disable=broad-exception-caught

supervisor/api/host.py

@@ -1,4 +1,5 @@
 """Init file for Supervisor host RESTful API."""
+
 import asyncio
 from contextlib import suppress
 import logging
@@ -163,8 +164,7 @@ class APIHost(CoreSysAttributes):
                 raise APIError() from err
         return possible_offset
 
-    @api_process_raw(CONTENT_TYPE_TEXT, error_type=CONTENT_TYPE_TEXT)
+    async def advanced_logs_handler(
-    async def advanced_logs(
         self, request: web.Request, identifier: str | None = None, follow: bool = False
     ) -> web.StreamResponse:
         """Return systemd-journald logs."""
@@ -218,3 +218,10 @@ class APIHost(CoreSysAttributes):
                     "Connection reset when trying to fetch data from systemd-journald."
                 ) from ex
             return response
+
+    @api_process_raw(CONTENT_TYPE_TEXT, error_type=CONTENT_TYPE_TEXT)
+    async def advanced_logs(
+        self, request: web.Request, identifier: str | None = None, follow: bool = False
+    ) -> web.StreamResponse:
+        """Return systemd-journald logs. Wrapped as standard API handler."""
+        return await self.advanced_logs_handler(request, identifier, follow)

tests/api/test_supervisor.py

@@ -6,7 +6,7 @@ from aiohttp.test_utils import TestClient
 import pytest
 
 from supervisor.coresys import CoreSys
-from supervisor.exceptions import StoreGitError, StoreNotFound
+from supervisor.exceptions import HassioError, StoreGitError, StoreNotFound
 from supervisor.store.repository import Repository
 
 from tests.api import common_test_api_advanced_logs
@@ -160,7 +160,7 @@ async def test_api_supervisor_fallback(
     api_client: TestClient, journald_logs: MagicMock, docker_logs: MagicMock
 ):
     """Check that supervisor logs read from container logs if reading from journald gateway fails badly."""
-    journald_logs.side_effect = OSError("Something bad happened!")
+    journald_logs.side_effect = HassioError("Something bad happened!")
 
     with patch("supervisor.api._LOGGER.exception") as logger:
         resp = await api_client.get("/supervisor/logs")
@@ -176,6 +176,19 @@ async def test_api_supervisor_fallback(
         b"\x1b[36m22-10-11 14:04:23 DEBUG (MainThread) [supervisor.utils.dbus] D-Bus call - org.freedesktop.DBus.Properties.call_get_all on /io/hass/os/AppArmor\x1b[0m",
     ]
 
+    journald_logs.reset_mock()
+
+    # also check generic Python error
+    journald_logs.side_effect = OSError("Something bad happened!")
+
+    with patch("supervisor.api._LOGGER.exception") as logger:
+        resp = await api_client.get("/supervisor/logs")
+        logger.assert_called_once_with(
+            "Failed to get supervisor logs using advanced_logs API"
+        )
+        assert resp.status == 200
+        assert resp.content_type == "text/plain"
+
 
 async def test_api_supervisor_reload(api_client: TestClient):
     """Test supervisor reload."""