pytest fixture for fastapi-jsonrpc. Check returned errors described in swagger (app.method(..., errors=[...]))

swagger.py

import collections
import contextlib
import traceback

import jsonrpcapi
import pytest

from testing import AnyDict


@pytest.fixture()
def all_captured_jsonrpc_error_responses(api_app):
    errors = collections.defaultdict(list)

    @contextlib.asynccontextmanager
    async def tracking_middleware(ctx: jsonrpcapi.JsonRpcContext):
        try:
            yield
        except Exception as exc:
            if not isinstance(exc, (jsonrpcapi.APIError, jsonrpcapi.BaseError)):
                exc_traceback = traceback.format_exception(
                    None,  # python >=3.5: The exc argument is ignored and inferred from the type of value.
                    value=exc,
                    tb=exc.__traceback__,
                    limit=30,
                )
                pytest.fail(
                    'Method should raise `jsonrpcapi.APIError` or `jsonrpcapi.BaseError`. '
                    'Common exception raised instead: \n' + ''.join(exc_traceback)
                )
            raise
        finally:
            if ctx.raw_response and 'result' not in ctx.raw_response:
                errors[ctx.method_route].append(ctx.raw_response)

    entrypoints = {r.entrypoint for r in api_app.routes if isinstance(r, jsonrpcapi.MethodRoute)}

    for ep in entrypoints:
        ep.middlewares.insert(0, tracking_middleware)

    try:
        yield errors
    finally:
        for ep in entrypoints:
            ep.middlewares.remove(tracking_middleware)


def _get_first_not_listed_in_method_errors(method_route, captured_error_responses):
    expected_errors = method_route.entrypoint.entrypoint_route.errors + method_route.errors

    expected_error_data = []

    # ValidationError всегда должен содержать подробности ошибки (APIError)
    expected_errors.remove(jsonrpcapi.ValidationError)
    for err_cls in expected_errors:
        if issubclass(err_cls, jsonrpcapi.APIError):
            # fmt: off
            expected_error_data.append({
                'code': jsonrpcapi.ValidationError.CODE,
                'message': jsonrpcapi.ValidationError.MESSAGE,
                'data': {
                    'errors': [AnyDict({
                        # Нам интересны только code и message
                        # object_name и meta это контекст, игнорируем его
                        'code': err_cls.code,
                        'message': err_cls.message,
                    })],
                },
            })
            # fmt: on
        else:
            err_resp = err_cls().get_resp()['error']
            # Оборачиваем в AnyDict, чтобы игнорировать доп. поля, которые может вернуть сервер
            # Обычно в них приходит контекстная информация
            expected_error_data.append(AnyDict(err_resp))

    for cap_err_resp in captured_error_responses:
        error_data = cap_err_resp['error']
        if error_data not in expected_error_data:
            return error_data

    return None


@pytest.fixture()
def _check_all_captured_jsonrpc_error_responses_listed_in_method_errors(all_captured_jsonrpc_error_responses):
    yield

    for method_route, captured_error_responses in all_captured_jsonrpc_error_responses.items():
        not_listed_error = _get_first_not_listed_in_method_errors(method_route, captured_error_responses)
        if not_listed_error is not None:
            pytest.fail(f'Error {not_listed_error!r} not listed in {method_route.name!r} method errors, but returned')