[英]How to mock AWS S3 with aiobotocore
我有一個項目使用 aiohttp 和 aiobotocore 來處理 AWS 中的資源。 我正在嘗試測試與 AWS S3 一起使用的類,並且我正在使用 moto 來模擬 AWS。 對於使用同步代碼的示例(來自 moto 文檔的示例),模擬效果很好
import boto3
from moto import mock_s3
class MyModel(object):
def __init__(self, name, value):
self.name = name
self.value = value
def save(self):
s3 = boto3.client('s3', region_name='us-east-1')
s3.put_object(Bucket='mybucket', Key=self.name, Body=self.value)
def test_my_model_save():
with mock_s3():
conn = boto3.resource('s3', region_name='us-east-1')
conn.create_bucket(Bucket='mybucket')
model_instance = MyModel('steve', 'is awesome')
model_instance.save()
body = conn.Object('mybucket', 'steve').get()['Body'].read().decode("utf-8")
assert body == 'is awesome'
但是,在將其重寫為使用 aiobotocore 模擬后不起作用 - 在我的示例中它連接到真正的 AWS S3。
import aiobotocore
import asyncio
import boto3
from moto import mock_s3
class MyModel(object):
def __init__(self, name, value):
self.name = name
self.value = value
async def save(self, loop):
session = aiobotocore.get_session(loop=loop)
s3 = session.create_client('s3', region_name='us-east-1')
await s3.put_object(Bucket='mybucket', Key=self.name, Body=self.value)
def test_my_model_save():
with mock_s3():
conn = boto3.resource('s3', region_name='us-east-1')
conn.create_bucket(Bucket='mybucket')
loop = asyncio.get_event_loop()
model_instance = MyModel('steve', 'is awesome')
loop.run_until_complete(model_instance.save(loop=loop))
body = conn.Object('mybucket', 'steve').get()['Body'].read().decode("utf-8")
assert body == 'is awesome'
所以我在這里的假設是 moto 不能與 aiobotocore 一起正常工作。 如果我的源代碼類似於第二個示例,我如何有效地模擬 AWS 資源?
來自moto
的模擬不起作用,因為它們使用同步 API。 但是,您可以啟動moto
服務器並配置aiobotocore
以連接到此測試服務器。 查看 aiobotocore 測試以獲取靈感。
使用 AWS 的 stubber 應該可以解決問題。 以下是我在龍卷風應用程序中執行 aws 讀取操作的方法:
import aiobotocore
from botocore.stub import Stubber
from tornado.testing import AsyncTestCase
from aiobotocore.response import StreamingBody
class RawStream(io.BytesIO):
async def __aenter__(self):
return self
async def __aexit__(self, exc_type, exc_val, exc_tb):
pass
async def read(self, n):
return super().read(n)
class S3TestCase(AsyncTestCase):
def setUp(self):
super().setUp()
session = aiobotocore.get_session()
self.client = session.create_client("s3", region_name="AWS_S3_REGION",
aws_secret_access_key="AWS_SECRET_ACCESS_KEY",
aws_access_key_id="AWS_ACCESS_KEY_ID")
@tornado.testing.gen_test
def test_read(self):
stubber = Stubber(self.client)
stubber.add_response("get_object",
{"Body": StreamingBody(raw_stream=RawStream(self.binary_content), content_length=128),
"ContentLength": 128},
expected_params={"Bucket": "AWS_S3_BUCKET",
"Key": "filename"})
stubber.activate()
response = await client.get_object(Bucket="AWS_S3_BUCKET", Key="filename")
寫操作應該類似。 希望這將引導您朝着正確的方向前進。
有關 stubber 的更多信息: https ://botocore.amazonaws.com/v1/documentation/api/latest/reference/stubber.html
我認為 Sebastian Brestins 的回答應該是公認的。 我將發布這個新答案,因為自發布以來發生了一些變化,例如 python 3.8 現在支持異步測試用例,aioboto3 客戶端現在是上下文管理器。
使用 python 3.8 的最小示例如下所示:
from unittest import IsolatedAsyncioTestCase
import aioboto3
from botocore.stub import Stubber
class Test(IsolatedAsyncioTestCase):
async def asyncSetUp(self):
self._s3_client = await aioboto3.client('s3').__aenter__()
self._s3_stub = Stubber(self._s3_client)
async def asyncTearDown(self):
await self._s3_client.__aexit__(None, None, None)
async def test_case(self):
self._s3_stub.add_response(
"get_object",
{"Body": "content"},
expected_params={"Bucket": "AWS_S3_BUCKET", "Key": "filename"}
)
self._s3_stub.activate()
response = await self._s3_client.get_object(Bucket="AWS_S3_BUCKET", Key="filename")
self.assertEquals(response, "content")
這是來自 aiobotocore 的 mock_server.py 沒有 pytest:
# Initially from https://raw.githubusercontent.com/aio-libs/aiobotocore/master/tests/mock_server.py
import shutil
import signal
import subprocess as sp
import sys
import time
import requests
_proxy_bypass = {
"http": None,
"https": None,
}
def start_service(service_name, host, port):
moto_svr_path = shutil.which("moto_server")
args = [sys.executable, moto_svr_path, service_name, "-H", host,
"-p", str(port)]
process = sp.Popen(args, stdin=sp.PIPE, stdout=sp.PIPE, stderr=sp.DEVNULL)
url = "http://{host}:{port}".format(host=host, port=port)
for _ in range(30):
if process.poll() is not None:
break
try:
# we need to bypass the proxies due to monkeypatches
requests.get(url, timeout=0.1, proxies=_proxy_bypass)
break
except requests.exceptions.RequestException:
time.sleep(0.1)
else:
stop_process(process)
raise AssertionError("Can not start service: {}".format(service_name))
return process
def stop_process(process, timeout=20):
try:
process.send_signal(signal.SIGTERM)
process.communicate(timeout=timeout / 2)
except sp.TimeoutExpired:
process.kill()
outs, errors = process.communicate(timeout=timeout / 2)
exit_code = process.returncode
msg = "Child process finished {} not in clean way: {} {}" \
.format(exit_code, outs, errors)
raise RuntimeError(msg)
我們可以使用 moto[server] 創建 S3 服務器,然后用它創建一個類似於aioboto3的 pytest 夾具
@pytest.yield_fixture(scope='session')
def s3_server():
host = 'localhost'
port = 5002
url = 'http://{host}:{port}'.format(host=host, port=port)
process = start_service('s3', host, port)
yield url
stop_process(process)
然后patch('aiobotocore.AioSession.create_client')
return_value with aiobotocore.get_session().create_client('s3', region_name='us-east-1', end_point_url=s3_server)
如下
async with aiobotocore.get_session().create_client('s3', region_name='us-east-1', end_point_url=s3_server) as client:
with patch('aiobotocore.AioSession.create_client') as mock:
mock.return_value = client
# Test your code
不幸的是,這不是一個完整的答案,但有一個拉取請求添加了已開放 6 個月的此功能: https ://github.com/aio-libs/aiobotocore/pull/766
當我為 asyncio 處理類似問題時,我為同步對象手動編碼了“異步”包裝器。
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.