aioboto3 mocking with Pytest and Moto

This is a Pytest plugin that sets up a Moto background service and patch the aioboto3 session to forward all calls to it. This is designed to work against any calls that create an aiobotocore3.Session() or botocore3.Session() automatically. This means you should not have to change any implementation code for how you are managing the aioboto3 Session.

Most of the code for this came from the aioboto3 tests themselves at https://github.com/terrycain/aioboto3/blob/92a7a9b8a32615ab6a9ea51ef360475ede94bb1f/tests/mock_server.py. Divergence in this gist:

• Only initializes a moto server for S3
• Includes a sustainable pattern for adding additional AWS mocked services
• Fully type-hinted

Running the example test

• Poetry 1.6+
• Python 3.10+ (although probably Python 3.7+ will work)

poetry install
poetry run pytest

Example output:

=========================================================================================================== test session starts ===========================================================================================================
platform darwin -- Python 3.11.6, pytest-7.4.3, pluggy-1.3.0
rootdir: /Users/phillip/pytest-aioboto3
configfile: pyproject.toml
testpaths: tests
plugins: asyncio-0.21.1, aioboto3-0.1.0
asyncio: mode=Mode.AUTO
collected 1 item

tests/test_s3.py .                                                                                                                                                                                                                  [100%]

============================================================================================================ 1 passed in 0.94s ============================================================================================================

Installation

pip install pytest-aioboto3

Usage

Inject the included aioboto3_s3_client fixture:

async def test_aio_aws_bucket_access(aioboto3_s3_client: S3Client) -> None:
    resp = await aioboto3_s3_client.list_buckets()
    ...

Or create a new Session yourself by injecting the moto_patch_session fixture:

async def test_some_s3_thing(moto_patch_session: None) -> None:
    session = aioboto3.Session(region_name="us-east-1")
    async with session.client("s3", region_name="us-east-1") as client:  # type: S3Client
        yield client