Files
familienarchiv/ocr-service/test_metrics.py
Marcel 4bb6685edb test(ocr): assert http_* metrics appear after an /ocr request
Locks down AC1: prometheus-fastapi-instrumentator must keep auto-exposing
http_requests_total and http_request_duration_seconds for application
traffic, not just register the /metrics endpoint.

Refs #652

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-05-21 16:00:33 +02:00

59 lines
2.4 KiB
Python

"""Tests for Prometheus metrics exposed by the OCR service.
Each test that asserts on a counter/gauge value uses a fresh CollectorRegistry
(see decision #3 on issue #652) to keep the metrics isolated between tests.
"""
from unittest.mock import AsyncMock, patch
import pytest
from httpx import ASGITransport, AsyncClient
from PIL import Image
from main import app
@pytest.mark.asyncio
async def test_metrics_endpoint_returns_200():
"""`GET /metrics` returns 200 with Prometheus exposition content."""
with patch("main.kraken_engine.load_models"), \
patch("main.load_spell_checker"):
async with AsyncClient(transport=ASGITransport(app=app), base_url="http://test") as client:
response = await client.get("/metrics")
assert response.status_code == 200
assert "text/plain" in response.headers.get("content-type", "")
@pytest.mark.asyncio
async def test_metrics_includes_http_request_metrics_after_ocr_call():
"""After a request to /ocr, `/metrics` exposes auto-instrumented http_* metrics."""
mock_images = [Image.new("RGB", (100, 100))]
mock_blocks = [{"pageNumber": 1, "x": 0.0, "y": 0.0, "width": 1.0, "height": 1.0,
"polygon": None, "text": "hi", "words": []}]
with patch("main.kraken_engine.load_models"), \
patch("main.load_spell_checker"), \
patch("main._download_and_convert_pdf", new_callable=AsyncMock, return_value=mock_images), \
patch("main.preprocess_page", side_effect=lambda img: img), \
patch("main.surya_engine.extract_blocks", return_value=mock_blocks):
async with AsyncClient(transport=ASGITransport(app=app), base_url="http://test") as client:
# Models need to be loaded for /ocr to accept requests; force the flag.
import main as main_module
main_module._models_ready = True
try:
ocr_response = await client.post("/ocr", json={
"pdfUrl": "http://minio/doc.pdf",
"scriptType": "TYPEWRITER",
"language": "de",
})
assert ocr_response.status_code == 200, ocr_response.text
metrics_response = await client.get("/metrics")
finally:
main_module._models_ready = False
body = metrics_response.text
assert "http_requests_total" in body
assert "http_request_duration_seconds" in body