Coroutine 'lifespan' not awaited

[daudln]

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Example Code

from contextlib import asynccontextmanager

from faker import Faker
from fastapi import FastAPI

@asynccontextmanager
async def app_lifespan(app: FastAPI):
    for _ in range(100):
        await User.create(
            name=faker.name(),
            email=faker.email(),
        )

app = FastAPI(lifespan=app_lifespan)

register_tortoise(
    app,
    db_url="sqlite://data.sqlite3",
    modules={"models": [__name__]},
    generate_schemas=True,
)


if __name__ == "__main__":
    uvicorn.run("testapp:app", port=7000, reload=True)

Description

I'm encountering an error with FastAPI's lifespan coroutine

I'm trying to use the lifespan functionality in a FastAPI application to perform some startup tasks, like creating users in this case. However, I'm running into the error "coroutine 'lifespan' was never awaited" when running the application with uvicorn.

Expected Behavior

I expect uvicorn to automatically await the app_lifespan coroutine, which would trigger the defined startup logic before the application starts handling requests. This would ensure tasks like user creation happen before the app is live.

Current Behavior

The error message indicates that uvicorn is not awaiting the app_lifespan coroutine.

Operating System

Linux

Operating System Details

Ubuntu 23.10

FastAPI Version

0.110.0

Pydantic Version

2.6.4

Python Version

3.10.9

Additional Context

No response

[Kludex]

Missing yield on lifespan.

[daudln]

When I add yield statement like this

@asynccontextmanager
async def app_lifespan(app: FastAPI):
    for _ in range(100):
        await User.create(
            name=faker.name(),
            email=faker.email(),
        )
    yield

TypeError: 'NoneType' object is not iterable #6400 which I answered it, and goes perfect if app_lifespan is not applied to FastAPI app initialization

[Kludex]

Can you reproduce this without tortoise?

[daudln]

No!
Thank you, I think this issue is for tortoise integration with FastAPI, the app is running after commenting the tortoise ORM logic.

@asynccontextmanager
async def app_lifespan(app: FastAPI):
    # for _ in range(100):
    #     await User.create(
    #         name=faker.name(),
    #         email=faker.email(),
    #     )
    yield

[daudln]

I have reported it to Tortoise ORM repo tortoise-orm/issues/1576 may be they can fix it.