feat: add openmetrics support & endpoint

tests/ahriman/web/middlewares/test_metrics_handler.py

@@ -0,0 +1,59 @@
+import importlib
+import pytest
+import sys
+
+import ahriman.web.middlewares.metrics_handler as metrics_handler
+
+from aiohttp.web import HTTPNotFound
+from pytest_mock import MockerFixture
+from unittest.mock import AsyncMock
+
+
+async def test_metrics(mocker: MockerFixture) -> None:
+    """
+    must return metrics methods if library is available
+    """
+    metrics_mock = AsyncMock()
+    mocker.patch.object(metrics_handler, "aiohttp_openmetrics", metrics_mock)
+
+    await metrics_handler.metrics(42)
+    metrics_mock.metrics.assert_called_once_with(42)
+
+
+async def test_metrics_dummy(mocker: MockerFixture) -> None:
+    """
+    must raise HTTPNotFound if no module found
+    """
+    mocker.patch.object(metrics_handler, "aiohttp_openmetrics", None)
+    with pytest.raises(HTTPNotFound):
+        await metrics_handler.metrics(None)
+
+
+async def test_metrics_handler() -> None:
+    """
+    must return metrics handler if library is available
+    """
+    assert metrics_handler.metrics_handler() == metrics_handler.aiohttp_openmetrics.metrics_middleware
+
+
+async def test_metrics_handler_dummy(mocker: MockerFixture) -> None:
+    """
+    must return dummy handler if no module found
+    """
+    mocker.patch.object(metrics_handler, "aiohttp_openmetrics", None)
+    handler = metrics_handler.metrics_handler()
+
+    async def handle(result: int) -> int:
+        return result
+
+    assert await handler(42, handle) == 42
+
+
+def test_import_openmetrics_missing(mocker: MockerFixture) -> None:
+    """
+    must correctly process missing module
+    """
+    mocker.patch.dict(sys.modules, {"aiohttp_openmetrics": None})
+    importlib.reload(metrics_handler)
+
+    assert metrics_handler.aiohttp_openmetrics is None

tests/ahriman/web/schemas/test_any_schema.py

@@ -0,0 +1 @@
+# schema testing goes in view class tests

tests/ahriman/web/views/v1/status/test_view_v1_status_metrics.py

@@ -0,0 +1,35 @@
+import pytest
+
+from aiohttp.test_utils import TestClient
+from aiohttp.web import Response
+from pytest_mock import MockerFixture
+
+from ahriman.models.user_access import UserAccess
+from ahriman.web.views.v1.status.metrics import MetricsView
+
+
+async def test_get_permission() -> None:
+    """
+    must return correct permission for the request
+    """
+    for method in ("GET",):
+        request = pytest.helpers.request("", "", method)
+        assert await MetricsView.get_permission(request) == UserAccess.Unauthorized
+
+
+def test_routes() -> None:
+    """
+    must return correct routes
+    """
+    assert MetricsView.ROUTES == ["/api/v1/metrics"]
+
+
+async def test_get(client: TestClient, mocker: MockerFixture) -> None:
+    """
+    must return service metrics
+    """
+    metrics_mock = mocker.patch("ahriman.web.views.v1.status.metrics.metrics", return_value=Response())
+
+    response = await client.get("/api/v1/metrics")
+    assert response.ok
+    metrics_mock.assert_called_once_with(pytest.helpers.anyvar(int))