Test fixtures with scope set to session

I am using pytest-sanic to test my sanic application, which communicates with a database layer running in a docker container and I am having difficulty achieving the following test setup:

Expected Setup

1. Spawn one database container for the entire test suite
2. Setup the database and tables inside the container required by the app
3. yield a session scoped fixture to the app
4. Run tests
5. Perform teardown.

Sample Code

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
Configuration for testing fixtures
"""
try:
    import pytest
    import docker
    from app import app as test_app
    from utilities.database_setup import create_databases, create_tables
except Exception as e:
    raise e

@pytest.yield_fixture
def app():
    yield test_app

@pytest.fixture
def test_cli(loop, app, test_client):
    return loop.run_until_complete(test_client(app))

@pytest.fixture(scope="session", autouse=True)
async def database_setup():
    """ Setup DB Layer for the App """
    print('Setting up pytest session!')
    client = docker.from_env()
    assert client.ping() is True, "Unable to connect to docker."
    print('spawning db container...')
    container = client.containers.run(
        image='redis:latest',
        ports={6380:  6380},
        detach=True
    )
    print('db container running...')
    print('Container ID: {}'.format(container.id))
    db_host = "localhost"
    db_port =  6380
    print('setting up databases...')
    await create_databases(db_host, db_port)
    print('setting up tables...')
    await create_tables(db_host, db_port)
    yield
    print("stopping db container")
    container.kill()

Error

ScopeMismatch: 
You tried to access the 'function' scoped fixture 'loop' with a 'session' scoped request object, involved factories

Alternatives

I am also open to using other alternatives to achieve this test setup since I am not tied to this approach.

Any help or suggestions will be greatly appreciated.

[shinybrar]

I fixed the issue, by starting the database + app configurations through docker-compose.

[jackey8616]

I’m not sure this would help you or not. Long days ago I faced same issue as you. I want to make the test running under just one instance, so I use module scope. And the solution I found is to make everything be module scope.

Here is my conftest.py check it out.

import pytest
import asyncio
from pytest_sanic.utils import TestClient

from sanic import Sanic
from app import index
from stage import add_route as stage_add_route


@pytest.yield_fixture(scope='module')
def app():
    app = Sanic()
    app.add_route(index, '/', methods=['GET'])
    stage_add_route(app)
    yield app


@pytest.fixture(scope='module')
def loop():
    # Reference from pytest_sanic.plugin#loop to give a new scope.
    loop = asyncio.get_event_loop()
    yield loop


@pytest.fixture(scope='module')
def test_client(loop):
    # Reference from pytest_sanic.plugin#test_client to give a new scope.
    clients = []

    async def create_client(app, **kwargs):
        client = TestClient(app, loop=loop, **kwargs)
        await client.start_server()
        clients.append(client)
        return client

    yield create_client

    if clients:
        for client in clients:
            loop.run_until_complete(client.close())


@pytest.fixture(scope='module')
def test_cli(loop, app, test_client):
yield loop.run_until_complete(test_client(app))

Also, since test_client is deprecated, so just change to sanic_client and do the same thing.

Regards.