Testing¶

The `pytest` Framework¶

Colibris uses pytest to provide an integrated testing framework. All features, plugins and common practices available with pytest are available with Colibris as well.

Writing Tests¶

One should simply place tests in the ${PACKAGE}/tests package. The pytest discovery mechanism will recursively look for modules starting with test_ and will run any function that starts with test_ or ends with _test.

The following functions, placed in a file named e.g. test_health.py will test the health status API endpoint:

async def test_health_check_healthy(web_app_client):
    resp = await web_app_client.get('/health')
    assert resp.status == 200

    j = await resp.json()
    assert j == 'healthy'


async def test_health_check_db_down(web_app_client):
    persist.get_database().drop()

    resp = await web_app_client.get('/health')
    assert resp.status == 500

    j = await resp.json()
    assert j['code'] == 'unhealthy'

Testing Utilities & Fixtures¶

pytest recommends building tests around fixtures. Colibris provides the web_app_client fixture which wraps the aiohttp_client fixture and allows simulating HTTP requests “directly”, bypassing any network layer.

Other testing utilities can be found in the utils module:

from colibris.test import utils 

For validating enveloped API responses, one can then use utils.assert_is_envelope:

resp = await web_app_client.get('/users')
assert resp.status == 200

j = await resp.json()
utils.assert_is_envelope(j, count=2)

The `test` Management Command¶

Running the tests is achieved by running the test management command:

./${PACKAGE}/manage.py test

Any arguments passed to this command are passed internally to pytest. Running pytest directly is not recommended and will probably fail.

Test Database¶

Colibris will use the TEST_DATABASE setting for persistence when running tests. In the absence of a field in this setting (which is by default), corresponding fields from DATABASE setting will be used, but name will be prefixed with test_.

The test database is created at the setup phase of each test and dropped at the teardown phase. Its structure is created using migration scripts. Populating it with data is the responsibility of the test writer.

The `fixtures` Module¶

The ./${PACKAGE}/tests/fixtures.py module can be used to define project-specific testing fixtures as well as constants. Here’s an example of a fixture that creates a test user in the database:

@pytest.fixture
def test_user():
    yield models.User.create(username='test_user', password='test_password',
                             first_name='Test', last_name='User',
                             email='testuser@example.com')