fake_session_maker
The fake_session_maker
is a SQLAlchemy and Pytest-based package designed to facilitate
database testing by replacing a classic SQLAlchemy SessionMaker
context manager.
Features
- Replaces the SQLAlchemy
SessionMaker
context manager with a "read-only" session during tests. - Rollbacks database state at the end of each test, ensuring isolation between tests.
- Simple fixture-based usage integrates smoothly with your Pytest suite.
Drawbacks
Code that plan to be tested using fake_session_maker
have the following limitations:
- Prevent the use of factory_boy automated build and bulk. Each object needs to be created and added to the session manually.
Installation
pip install fake_session_maker
Usage
Define the fixture
Below is an example of how to use fake_session_maker in a pytest fixture:
import pytest
from fake_session_maker import fsm
# Assuming Namespace is where the session_maker is defined
@pytest.fixture
def fake_session_maker():
with fsm(
db_url="sqlite:///tests/test.sqlite",
namespace=Namespace,
symbol_name="session_maker",
) as fake_session_maker_:
yield fake_session_maker_
# Now, you can use fake_session_maker in your tests
Use the fixture
Below is an example of how to use fake_session_maker fixture in a test:
# Each test will have a fresh database, empty of any data
@pytest.mark.parametrize("name", ["jane", "joe"])
def test_create_example(fake_session_maker, name):
result = create_example('test')
assert result == 'success'
with fake_session_maker() as session:
# Each time we check, only the data created in this test will be present
assert session.query(models.User).count() == 1
See the tests.test_fsm.py directory for a full example.
Contributing
Contributions are welcome! Please see CONTRIBUTING.md for more details.
Testing
If you want to run the tests locally, you can follow instructions here: CONTRIBUTING.md #testing.
License
Distributed under the MIT License. See LICENSE for more information.