Testing an app with background tasks using ReusableClient

Questions and Help
#1

I’m looking to test an app that performs some work in background tasks. And I’m using the ReusableClient because I need to test scenarios that are made up of a sequence of requests. But it’s not working:

import asyncio
import time
from sanic import Sanic, json
from sanic_testing.reusable import ReusableClient

app = Sanic("Demo")


@app.before_server_start
async def init(app):
    app.ctx.val = False


async def setval(app):
    await asyncio.sleep(1)
    app.ctx.val = True


@app.get("/val")
async def getval(request):
    request.app.add_task(setval)
    return json(app.ctx.val)


def test_app():
    client = ReusableClient(app)
    with client:
        _, resp = client.get("/val")
        assert resp.json is False

        time.sleep(3)
        _, resp = client.get("/val")
        assert resp.json is True, resp.json

Running the test_app() test through pytest fails, because val is never updated to True. I don’t think the background tasks are being launched here, and I can’t figure out why…

Would greatly appreciate any pointers or suggestions on how to test such apps.

#2

Add this little snippet:

from sanic.application.constants import ServerStage

...

def test_app():
    client = ReusableClient(app)
    with client:
        for info in app.state.server_info:
            info.stage = ServerStage.SERVING
        ...

That should get it to work as expected.

1 Like
#3

This does the trick! Thank you!