great-ai/tests/test_prediction_contract.py
2026-10-28 22:32:14 +00:00

80 lines
2.9 KiB
Python

from typing import List
import pytest
from fastapi.testclient import TestClient
from great_ai import GreatAI, parameter
from pydantic import BaseModel
class Score(BaseModel):
label: str
confidence: float
@pytest.mark.parametrize("is_async", [False, True])
def test_custom_validation_returns_client_error_but_prediction_failures_do_not(
isolated_context: None, is_async: bool
) -> None:
@parameter("value", validate=lambda value: value > 0)
def predict(value: int) -> int:
if value == 7:
raise ValueError("prediction failed")
return value
@parameter("value", validate=lambda value: value > 0)
async def predict_async(value: int) -> int:
return predict(value)
service = GreatAI.create(predict_async if is_async else predict)
with TestClient(service.app) as client:
rejected = client.post("/predict", json={"value": -1})
assert rejected.status_code == 422
assert "did not pass validation" in rejected.json()["detail"]
assert client.post("/predict", json={"value": "wrong"}).status_code == 422
assert client.post("/predict", json={"value": 7}).status_code == 500
valid = client.post("/predict", json={"value": 1})
assert valid.status_code == 200
assert valid.json()["output"] == 1
@pytest.mark.parametrize("is_async", [False, True])
def test_openapi_preserves_typed_nested_prediction_outputs(
isolated_context: None, is_async: bool
) -> None:
def predict(text: str) -> List[Score]:
return [Score(label=text, confidence=0.75)]
async def predict_async(text: str) -> List[Score]:
return predict(text)
service = GreatAI.create(predict_async if is_async else predict)
with TestClient(service.app) as client:
schema = client.get("/openapi.json").json()
response_ref = schema["paths"]["/predict"]["post"]["responses"]["200"][
"content"
]["application/json"]["schema"]["$ref"].split("/")[-1]
output = schema["components"]["schemas"][response_ref]["properties"]["output"][
"anyOf"
][0]
assert output == {
"items": {"$ref": "#/components/schemas/Score"},
"type": "array",
}
assert (
schema["components"]["schemas"]["Score"]["properties"]["confidence"]["type"]
== "number"
)
response = client.post("/predict", json={"text": "cat"})
assert response.status_code == 200
assert response.json()["output"] == [{"label": "cat", "confidence": 0.75}]
def test_http_rejects_outputs_that_violate_the_return_annotation(
isolated_context: None,
) -> None:
@GreatAI.create
def predict(value: int) -> int:
return "invalid" # type: ignore[return-value]
with TestClient(predict.app, raise_server_exceptions=False) as client:
assert client.post("/predict", json={"value": 1}).status_code == 500