Add "lines" and "verbose" query parameters for advanced logs (#5287)

Since headers are clumsy considering the Core proxy between the frontend
and Supervisor, add a way to adjust number of lines and verbose log
format using query parameters as well. If both query parameters and
headers are supplied, prefer the former, as it's more prominent when
reading through the request logs.

supervisor/api/host.py

@@ -222,10 +222,14 @@ class APIHost(CoreSysAttributes):
                 "supported for now."
             )
 
-        if request.headers[ACCEPT] == CONTENT_TYPE_X_LOG:
+        if "verbose" in request.query or request.headers[ACCEPT] == CONTENT_TYPE_X_LOG:
             log_formatter = LogFormatter.VERBOSE
 
-        if RANGE in request.headers:
+        if "lines" in request.query:
+            lines = request.query.get("lines", DEFAULT_RANGE)
+            # entries=cursor[[:num_skip]:num_entries]
+            range_header = f"entries=:-{lines}:"
+        elif RANGE in request.headers:
             range_header = request.headers.get(RANGE)
         else:
             range_header = f"entries=:-{DEFAULT_RANGE}:"

tests/api/test_host.py

@@ -238,6 +238,51 @@ async def test_advanced_logs(
     )
 
 
+async def test_advaced_logs_query_parameters(
+    api_client: TestClient,
+    coresys: CoreSys,
+    journald_logs: MagicMock,
+    journal_logs_reader: MagicMock,
+):
+    """Test advanced logging API entries controlled by query parameters."""
+    # Check lines query parameter
+    await api_client.get("/host/logs?lines=53")
+    journald_logs.assert_called_once_with(
+        params={"SYSLOG_IDENTIFIER": coresys.host.logs.default_identifiers},
+        range_header="entries=:-53:",
+        accept=LogFormat.JOURNAL,
+    )
+
+    journald_logs.reset_mock()
+
+    # Check verbose logs formatter via query parameter
+    await api_client.get("/host/logs?verbose")
+    journald_logs.assert_called_once_with(
+        params={"SYSLOG_IDENTIFIER": coresys.host.logs.default_identifiers},
+        range_header=DEFAULT_RANGE,
+        accept=LogFormat.JOURNAL,
+    )
+    journal_logs_reader.assert_called_with(ANY, LogFormatter.VERBOSE)
+
+    journal_logs_reader.reset_mock()
+    journald_logs.reset_mock()
+
+    # Query parameters should take precedence over headers
+    await api_client.get(
+        "/host/logs?lines=53&verbose",
+        headers={
+            "Range": "entries=:-19:10",
+            "Accept": "text/plain",
+        },
+    )
+    journald_logs.assert_called_once_with(
+        params={"SYSLOG_IDENTIFIER": coresys.host.logs.default_identifiers},
+        range_header="entries=:-53:",
+        accept=LogFormat.JOURNAL,
+    )
+    journal_logs_reader.assert_called_with(ANY, LogFormatter.VERBOSE)
+
+
 async def test_advanced_logs_boot_id_offset(
     api_client: TestClient, coresys: CoreSys, journald_logs: MagicMock
 ):