Question

说我想模拟以下内容：

session = boto3.Session(profile_name=profile)
resource = session.resource('iam')
iam_users = resource.users.all()
policies = resource.policies.filter(Scope='AWS', OnlyAttached=True, PolicyUsageFilter='PermissionsPolicy')

我该如何开始在pytest中模拟呢？我可以通过创建一个虚拟类和必要的属性来创建模拟对象，但是我怀疑这是错误的方法。

一些其他详细信息，这是我要测试的内容：

def test_check_aws_profile(self, mocker):
    mocked_boto3 = mocker.patch('myapp.services.utils.boto3.Session')
    mocker.patch(mocked_boto3.client.get_caller_identity.get, return_value='foo-account-id')
    assert 'foo-account-id' == my_func('foo')

#in myapp.services.utils.py
def my_func(profile):
    session = boto3.Session(profile_name=profile)
    client = session.client('sts')
    aws_account_number = client.get_caller_identity().get('Account')
    return aws_account_number

但是我似乎不太能够正确修补此问题。我正在尝试使其能够修补会话和该方法中的函数调用

我尝试使用moto并得到了它：

@mock_sts
def test_check_aws_profile(self):
    session = boto3.Session(profile_name='foo')
    client = session.client('sts')
    client.get_caller_identity().get('Account')

但是我遇到了

>           raise ProfileNotFound(profile=profile_name)
E           botocore.exceptions.ProfileNotFound: The config profile (foo) could not be found

所以好像没有嘲笑什么：|

Answer 1

我不确定您到底想要什么，所以我给您一些开始。

例如，您让unittest.mock为您模拟一切。（有用的读物：https://docs.python.org/3/library/unittest.mock.html）

module.py：

import boto3

def function():
    session = boto3.Session(profile_name="foobar")
    client = session.resource("sts")
    return client.get_caller_identity().get('Account')

test_module.py：

from unittest.mock import patch

import module

@patch("module.boto3")  # this creates mock which is passed to test below
def test_function(mocked_boto):
    # mocks below are magically created by unittest.mock when they are accessed
    mocked_session = mocked_boto.Session()
    mocked_client = mocked_session.resource()
    mocked_identity = mocked_client.get_caller_identity()

    # now mock the return value of .get()
    mocked_identity.get.return_value = "foo-bar-baz"

    result = module.function()
    assert result == "foo-bar-baz"

    # we can make sure mocks were called properly, for example
    mocked_identity.get.assert_called_once_with("Account")

pytest运行的结果：

$ pytest
================================ test session starts ================================
platform darwin -- Python 3.7.6, pytest-5.3.2, py-1.8.1, pluggy-0.13.1
rootdir: /private/tmp/one
collected 1 item                                                                    

test_module.py .                                                              [100%]

================================= 1 passed in 0.09s =================================

我还建议安装pytest-socket并运行pytest --disable-socket，以确保您的测试不会偶然与网络通信。

Answer 2

尽管使用@Test public void test() { MyClass myClass = spy(myClass); doThrow(new StatusRuntimeException(Status.UNAVAILABLE)).when(myClass).newMethod(any()); // changed to call myClass.newMethod() instead of blahServiceBlockingStub.blah myClass.myExistingMethod(); }手动修补boto并没有错，但您也可以考虑使用moto之类的更高级别的测试实用程序。

Answer 3

如果要使用moto，则可以使用AWS_SHARED_CREDENTIALS_FILE环境变量，将其指向可以保存在测试文件夹中的虚拟凭证文件。您可以在那里定义个人资料。示例：

文件：test_stuff.py. dummy_aws_credentials

test_stuff.py：

import os
from pathlib import Path
import boto3
import pytest
from moto import mock_sts


@pytest.fixture(scope='module')
def aws_credentials():
    """Mocked AWS Credentials for moto."""
    moto_credentials_file_path = Path(__file__).parent.absolute() / 'dummy_aws_credentials'
    os.environ['AWS_SHARED_CREDENTIALS_FILE'] = str(moto_credentials_file_path)


@mock_sts
def test_check_aws_profile(aws_credentials):
    session = boto3.Session(profile_name='foo')
    client = session.client('sts')
    client.get_caller_identity().get('Account')

dummy_aws_credentials：

[foo]
aws_access_key_id = mock
aws_secret_access_key = mock

Moto在pytest中似乎没有嘲笑AWS交互

3 个答案: