tests/test_app_errors.py

import unittest
from unittest.mock import patch

from fastapi.testclient import TestClient

from app import app
from bucklake_ai.errors import InvalidScalerArtifact, ScalerArtifactNotFound


class AppErrorHandlerTests(unittest.TestCase):
    def _payload(self):
        return {
            "symbol": "AAPL",
            "published_at": "2026-04-15T12:30:00Z",
            "market_bars": {
                name: [
                    {
                        "open": 100.0 + i,
                        "close": 101.0 + i,
                        "high": 102.0 + i,
                        "low": 99.0 + i,
                        "volume": 1000.0 + i,
                        "amount": 0.0,
                    }
                    for i in range(30)
                ]
                for name in ("stock", "inx", "dj", "ixic", "ndx")
            },
        }

    def test_scaler_artifact_not_found_returns_503(self):
        with patch(
            "app.service.predict",
            side_effect=ScalerArtifactNotFound("missing scaler"),
        ):
            response = TestClient(app).post("/api/predict/v2", json=self._payload())

        self.assertEqual(response.status_code, 503)
        self.assertEqual(response.json()["error"], "scaler_artifact_not_found")

    def test_invalid_scaler_artifact_returns_503(self):
        with patch(
            "app.service.predict",
            side_effect=InvalidScalerArtifact("bad scaler"),
        ):
            response = TestClient(app).post("/api/predict/v2", json=self._payload())

        self.assertEqual(response.status_code, 503)
        self.assertEqual(response.json()["error"], "invalid_scaler_artifact")


if __name__ == "__main__":
    unittest.main()