Flask 和 pytest 中带有 500 状态码的模拟响应

Question

* 已编辑*

我想测试如果外部 API 将 return 500 状态代码会发生什么。

main.py

@app.route("/<a>/<b>", methods=["GET"])
def repo_info(a: str, b: str) -> Union[Response, str]:
    info = some_func(a, b)
    result = create_result_dict(some_func)
    return Response(
        response=json.dumps(result, ensure_ascii=False),
        status=200,
        mimetype="application/json",

@app.errorhandler(500)
def server_error(e):
    logging.exception(f"An error occurred during a request: {e}.")
    return Response(
        response="An internal error occurred. See logs for full stacktrace.",
        status=500,
    )

my_module.py

def some_func(a: str, b: str) -> Dict[str, str]:
    return json.loads(
        (requests.get(f"https://api.github.com/repos/{a}/{b}")).text
    )

我试过这段代码，但感觉像无头鸡：

from flask import Response
import pytest
import requests

from unittest.mock import patch
from requests.exceptions import HTTPError

@patch.object(my_module, "some_func")
def test_some_func(mocked):
    mocked.return_value = HTTPError()
    result = my_module.some_func()
    with pytest.raises(HTTPError):
        result == mocked

另外 HTTPError 不带参数，我如何传递信息，我想要 500 状态代码？

Answer 1

第一个问题是要获得 HTTPError 异常，您需要告诉 requests 使用 raise_for_status():

引发它

# my_module.py

import json
import requests
from typing import Dict

def some_func(a: str, b: str) -> Dict[str, str]:
    result = requests.get(f"https://api.github.com/repos/{a}/{b}")
    result.raise_for_status()

    return json.loads(result.text)

第二个问题是，要模拟它，您只想模拟请求（设置条件以及避免对 API 进行真正的调用），否则您确实想调用 some_func()。毕竟，那是测试它的想法。您可以按照您尝试的方式修补对象，但我建议您安装 requests-mock:

# test.py

import pytest
import requests_mock
from requests.exceptions import HTTPError
from my_module import some_func

def test_some_func():
    with requests_mock.mock() as m:
        m.get(requests_mock.ANY, status_code=500, text='some error')

        with pytest.raises(HTTPError):
            # You cannot make any assertion on the result
            # because some_func raises an exception and
            # wouldn't return anything
            some_func(a="a", b="b")

Flask 和 pytest 中带有 500 状态码的模拟响应

Mock response with 500 status code in flask and pytest

python

pytest

python-unittest

python-unittest.mock