tests/test_api_contract.py

from __future__ import annotations

from typing import AsyncGenerator

from fastapi import File, Request, UploadFile
from fastapi.testclient import TestClient

from src.core import security
from src.main import create_app
from src.repository import DeviceCredentials
from src.api.v1.endpoints import predict as predict_endpoint


async def _fake_validated_device(
    request: Request,
    image: UploadFile = File(..., alias="image"),
) -> AsyncGenerator[DeviceCredentials, None]:
    request.state.image = image
    yield DeviceCredentials(
        device_id="DEV-TEST-0001",
        api_key="sk_test_key",
        secret="secret",
        is_active=True,
    )


async def _fake_inference(_image_bytes: bytes) -> dict:
    return {
        "predicted_class": "Pure Milk",
        "confidence": 0.9231,
        "model_version": "v3.0.0",
        "latency_ms": 12,
        "status": "success",
    }


def test_core_routes_and_predict_response_shape(monkeypatch) -> None:
    app = create_app()
    app.dependency_overrides[security.get_validated_device] = _fake_validated_device
    monkeypatch.setattr(predict_endpoint, "run_inference", _fake_inference)

    with TestClient(app) as client:
        root = client.get("/")
        assert root.status_code == 200
        assert root.json()["service"] == "imageO_v3"

        live = client.get("/healthz")
        assert live.status_code == 200
        assert live.json() == {"status": "ok"}

        response = client.post(
            "/v1/predict",
            files={"image": ("sample.png", b"mock-bytes", "image/png")},
            headers={"X-API-Key": "sk_test_key"},
        )
        assert response.status_code == 200
        payload = response.json()
        assert set(payload.keys()) == {
            "predicted_class",
            "confidence",
            "model_version",
            "latency_ms",
            "status",
        }