Functional tests in Cyan

Hello!

My name is Timofey, I am a Python developer in the Cyan Platform team. Our team is developing tools for product developers. These are libraries: HTTP client, web server, database access libraries, and monitoring tools for microservices and the site as a whole, and integration with CI / CD, and much more.

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[[dependency]]
type = "postgres"
alias = "users"

[[dependency]]
type = "rabbitmq"

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cian-functional-test-utils deps up

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conftest.py :

@pytest.fixture(scope='session', autouse=True)
async def start(runner, pg):
    #           ,
    #          health-check.
    await runner.start_background_python_web()
    #       HTTP API,   RabbitMQ , 
    await runner.start_background_python_command('save-users-consumer')

@pytest.fixture(scope='session')
async def pg(postgres_service):
    db = await postgres_service.create_database_by_alias('users')
    #  `pathlib.Path`  .
    await db.execute_scripts(Path('database_schemas') / 'postgres.sql')
    return db

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async def test_v1_get_user(http, pg):  #   pg  conftest.py
    # arrange
    await pg.execute('INSERT INTO users (id, name) VALUES (1, "Bart")')
    # act
    response = await http.request('GET', '/v1/get-user/', params={'id': 1})
    # assert
    assert response.status == 200
    assert response.data == {'id': 1, 'name': 'Bart'}

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async def test_save_users_consumer(pg, queue_service):
    # arrange
    #      RabbitMQ ,
    #  ,    .
    await queue_service.wait_consumer(queue='save-users')
    # act
    await queue_service.publish(
        exchange='users',
        routing_key='user.created',
        payload={'id':1, 'name': 'Bart'},
    )
    await asyncio.sleep(0.5)  #  ,    
    # assert
    row = await pg.fetchrow('SELECT name FROM users WHERE id = 1')
    assert row['name'] == 'Bart'

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@pytest.fixture(scope='session')
async def users_mock(http_mock_service):
    #     ,    ,
    #    URL    .
    return await http_mock_service.make_microservice_mock('users')

def test_something(users_mock):
    # arrange
    stub = await users_mock.add_stub(
        method='GET',
        path='/v1/get-user/',
        response=MockResponse(body={'firstName': 'Bart', 'lastName': 'Simpson'}),
    )
    # act
    # do something
    # assert
    # ,        ?userId=234
    request = (await stub.get_requests())[0]
    assert request.params['userId'] == '234'

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