Expanded integration coverage and enforced test categories.

tests/unit/test_metrics.py

@@ -14,44 +14,20 @@
 
 """Unit tests for the Prometheus metrics module.
 
-Tests cover metric object registration and the MetricsServer HTTP endpoint.
+Tests cover metric object registration.
 """
 
-import errno
-import socket
-from dataclasses import dataclass
-from http import HTTPStatus
-from typing import TYPE_CHECKING, Literal, cast
-
-import aiohttp
 import pytest
 from prometheus_client import generate_latest
 
-from crabstero.metrics import MetricsServer, TcpMetricsAddress, UnixMetricsAddress
-
-if TYPE_CHECKING:
-    from collections.abc import AsyncGenerator
-    from pathlib import Path
+# Importing the module registers its Prometheus metrics with the default registry.
+import crabstero.metrics  # noqa: F401 - imported for registration side effects
 
 
-type MetricsTransport = Literal["tcp", "unix-socket"]
-
-
-@dataclass(frozen=True, slots=True)
-class MetricsEndpoint:
-    """Client details for one running metrics transport."""
-
-    base_url: str
-    unix_socket_path: str | None = None
-
-    def client_session(self) -> aiohttp.ClientSession:
-        """Create an aiohttp client session for this metrics transport."""
-        connector = (
-            aiohttp.UnixConnector(path=self.unix_socket_path)
-            if self.unix_socket_path is not None
-            else None
-        )
-        return aiohttp.ClientSession(connector=connector)
+@pytest.fixture(scope="module")
+def prometheus_output() -> str:
+    """Return Prometheus exposition text after module-level metric registration."""
+    return generate_latest().decode()
 
 
 class TestMetricObjects:
@@ -93,125 +69,6 @@ class TestMetricObjects:
             ),
         ],
     )
-    def test_metric_in_output(self, name: str) -> None:
+    def test_metric_in_output(self, prometheus_output: str, name: str) -> None:
         """Each declared metric appears in the Prometheus text output."""
-        output = generate_latest().decode()
-        assert name in output, f"{name} not found in Prometheus output"
-
-
-@pytest.fixture(
-    params=[
-        pytest.param("tcp", id="tcp"),
-        pytest.param("unix-socket", id="unix-socket"),
-    ],
-)
-async def metrics_endpoint(
-    request: pytest.FixtureRequest,
-    tmp_path: Path,
-) -> AsyncGenerator[MetricsEndpoint]:
-    """Start a MetricsServer on each supported transport."""
-    transport = cast("MetricsTransport", request.param)
-    match transport:
-        case "tcp":
-            server = MetricsServer(TcpMetricsAddress("127.0.0.1", 0))
-            await server.start()
-            endpoint = MetricsEndpoint(f"http://127.0.0.1:{server.port}")
-        case "unix-socket":
-            socket_path = tmp_path / "metrics.sock"
-            server = MetricsServer(UnixMetricsAddress(str(socket_path)))
-            await server.start()
-            endpoint = MetricsEndpoint(
-                "http://crabstero",
-                unix_socket_path=str(socket_path),
-            )
-
-    try:
-        yield endpoint
-    finally:
-        await server.stop()
-
-
-class TestMetricsServer:
-    """HTTP server serves Prometheus metrics on /metrics."""
-
-    async def test_serves_metrics_endpoint(
-        self,
-        metrics_endpoint: MetricsEndpoint,
-    ) -> None:
-        """GET /metrics returns 200 with metric output containing our metrics."""
-        async with (
-            metrics_endpoint.client_session() as session,
-            session.get(f"{metrics_endpoint.base_url}/metrics") as resp,
-        ):
-            assert resp.status == HTTPStatus.OK
-            body = await resp.text()
-            assert "crabstero_build_info" in body
-
-    async def test_non_metrics_path_returns_404(
-        self,
-        metrics_endpoint: MetricsEndpoint,
-    ) -> None:
-        """GET on an unknown path returns 404."""
-        async with (
-            metrics_endpoint.client_session() as session,
-            session.get(f"{metrics_endpoint.base_url}/notfound") as resp,
-        ):
-            assert resp.status == HTTPStatus.NOT_FOUND
-
-    async def test_unix_socket_mode_is_applied(self, tmp_path: Path) -> None:
-        """Configured Unix socket mode is applied after startup."""
-        socket_path = tmp_path / "metrics.sock"
-        server = MetricsServer(UnixMetricsAddress(str(socket_path), mode=0o666))
-        await server.start()
-        try:
-            assert socket_path.stat().st_mode & 0o777 == 0o666
-        finally:
-            await server.stop()
-
-    async def test_stale_unix_socket_path_is_recovered(
-        self,
-        tmp_path: Path,
-    ) -> None:
-        """Startup removes an abandoned Unix socket file left by a crash."""
-        socket_path = tmp_path / "metrics.sock"
-        with socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) as stale_socket:
-            stale_socket.bind(str(socket_path))
-
-        server = MetricsServer(UnixMetricsAddress(str(socket_path), mode=0o666))
-        await server.start()
-        try:
-            assert socket_path.stat().st_mode & 0o777 == 0o666
-            connector = aiohttp.UnixConnector(path=str(socket_path))
-            async with (
-                aiohttp.ClientSession(connector=connector) as session,
-                session.get("http://crabstero/metrics") as resp,
-            ):
-                assert resp.status == HTTPStatus.OK
-                body = await resp.text()
-                assert "crabstero_build_info" in body
-        finally:
-            await server.stop()
-
-    async def test_active_unix_socket_path_fails(
-        self,
-        tmp_path: Path,
-    ) -> None:
-        """Startup refuses to replace a Unix socket path that is still in use."""
-        socket_path = tmp_path / "metrics.sock"
-        with socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) as active_socket:
-            active_socket.bind(str(socket_path))
-            active_socket.listen(1)
-
-            server = MetricsServer(UnixMetricsAddress(str(socket_path)))
-            with pytest.raises(OSError, match="already in use") as exc_info:
-                await server.start()
-
-        assert exc_info.value.errno == errno.EADDRINUSE
-
-    async def test_non_socket_unix_path_fails(self, tmp_path: Path) -> None:
-        """Startup refuses to replace a non-socket path."""
-        socket_path = tmp_path / "metrics.sock"
-        socket_path.write_text("")
-        server = MetricsServer(UnixMetricsAddress(str(socket_path)))
-        with pytest.raises(FileExistsError):
-            await server.start()
+        assert name in prometheus_output, f"{name} not found in Prometheus output"