bambuddy/backend/tests/integration/test_metrics_api.py

"""Integration tests for Prometheus Metrics API endpoint.

Tests the /api/v1/metrics endpoint for Prometheus scraping.
"""

import pytest
from httpx import AsyncClient


class TestMetricsAPI:
    """Integration tests for /api/v1/metrics endpoint."""

    # ========================================================================
    # Metrics endpoint access control
    # ========================================================================

    @pytest.mark.asyncio
    @pytest.mark.integration
    async def test_metrics_disabled_returns_404(self, async_client: AsyncClient):
        """Verify metrics endpoint returns 404 when disabled."""
        # Ensure prometheus is disabled
        await async_client.put("/api/v1/settings/", json={"prometheus_enabled": False})

        response = await async_client.get("/api/v1/metrics")

        assert response.status_code == 404
        assert "not enabled" in response.json()["detail"].lower()

    @pytest.mark.asyncio
    @pytest.mark.integration
    async def test_metrics_enabled_without_token(self, async_client: AsyncClient):
        """Verify metrics endpoint works when enabled without token."""
        # Enable prometheus without token
        await async_client.put("/api/v1/settings/", json={"prometheus_enabled": True, "prometheus_token": ""})

        response = await async_client.get("/api/v1/metrics")

        assert response.status_code == 200
        assert response.headers["content-type"].startswith("text/plain")

    @pytest.mark.asyncio
    @pytest.mark.integration
    async def test_metrics_with_token_requires_auth(self, async_client: AsyncClient):
        """Verify metrics endpoint requires auth when token is set."""
        # Enable prometheus with token
        await async_client.put("/api/v1/settings/", json={"prometheus_enabled": True, "prometheus_token": "secret123"})

        # Request without auth
        response = await async_client.get("/api/v1/metrics")
        assert response.status_code == 401

        # Request with wrong token
        response = await async_client.get("/api/v1/metrics", headers={"Authorization": "Bearer wrongtoken"})
        assert response.status_code == 401

        # Request with correct token
        response = await async_client.get("/api/v1/metrics", headers={"Authorization": "Bearer secret123"})
        assert response.status_code == 200

    # ========================================================================
    # Metrics content validation
    # ========================================================================

    @pytest.mark.asyncio
    @pytest.mark.integration
    async def test_metrics_format(self, async_client: AsyncClient):
        """Verify metrics are in Prometheus text format."""
        # Enable prometheus
        await async_client.put("/api/v1/settings/", json={"prometheus_enabled": True, "prometheus_token": ""})

        response = await async_client.get("/api/v1/metrics")

        assert response.status_code == 200
        content = response.text

        # Check for Prometheus format markers
        assert "# HELP" in content
        assert "# TYPE" in content

    @pytest.mark.asyncio
    @pytest.mark.integration
    async def test_metrics_contains_expected_metrics(self, async_client: AsyncClient):
        """Verify expected metrics are present."""
        # Enable prometheus
        await async_client.put("/api/v1/settings/", json={"prometheus_enabled": True, "prometheus_token": ""})

        response = await async_client.get("/api/v1/metrics")

        assert response.status_code == 200
        content = response.text

        # Check for key metrics
        assert "bambuddy_printers_connected" in content
        assert "bambuddy_printers_total" in content
        assert "bambuddy_prints_total" in content
        assert "bambuddy_filament_used_grams" in content
        assert "bambuddy_print_time_seconds" in content
        assert "bambuddy_queue_pending" in content

    @pytest.mark.asyncio
    @pytest.mark.integration
    async def test_metrics_printer_metrics_when_no_printers(self, async_client: AsyncClient):
        """Verify printer metrics work when no printers configured."""
        # Enable prometheus
        await async_client.put("/api/v1/settings/", json={"prometheus_enabled": True, "prometheus_token": ""})

        response = await async_client.get("/api/v1/metrics")

        assert response.status_code == 200
        content = response.text

        # Should still have system metrics
        assert "bambuddy_printers_total" in content
        assert "bambuddy_printers_connected" in content

    # ========================================================================
    # Settings persistence
    # ========================================================================

    @pytest.mark.asyncio
    @pytest.mark.integration
    async def test_prometheus_settings_persist(self, async_client: AsyncClient):
        """Verify prometheus settings are saved correctly."""
        # Update settings
        await async_client.put("/api/v1/settings/", json={"prometheus_enabled": True, "prometheus_token": "mytoken"})

        # Read back settings
        response = await async_client.get("/api/v1/settings/")
        settings = response.json()

        assert settings["prometheus_enabled"] is True
        assert settings["prometheus_token"] == "mytoken"

        # Disable and verify
        await async_client.put("/api/v1/settings/", json={"prometheus_enabled": False})
        response = await async_client.get("/api/v1/settings/")
        settings = response.json()

        assert settings["prometheus_enabled"] is False