FastAPI: how to to Use Background Tasks with Dependency Injection for Async Functions
I'm trying to utilize FastAPI's background tasks feature alongside dependency injection for an asynchronous function, but I'm running into issues where the background task is not being executed as expected. Here's my current setup: ```python from fastapi import FastAPI, BackgroundTasks, Depends from sqlalchemy.orm import Session from myapp import get_db, MyModel app = FastAPI() async def process_data(data: str): # Simulate a long-running task await asyncio.sleep(10) print(f"Processed data: {data}") @app.post("/items/") async def create_item(item: MyModel, background_tasks: BackgroundTasks, db: Session = Depends(get_db)): # Store item in database (simulated) db.add(item) db.commit() # Schedule background task background_tasks.add_task(process_data, item.data) return {"message": "Item created, processing data in background."} ``` When I hit the endpoint, the response is returned immediately, as expected, but it seems like the background task is not being executed at all. I don't see any output from `print` statements in my console, and there are no errors thrown. I've also tried adding logging to see if the function is even being called, but nothing appears in my logs. I checked the FastAPI documentation to ensure that I was implementing it correctly, and it looks like I am. Both the `create_item` function and the `process_data` function are defined as async, and FastAPI should be able to handle them. Could this be an scenario with how FastAPI handles background tasks with async functions? Or is there something specific I might be missing in the setup? I'm using FastAPI version 0.68.0 and the latest version of SQLAlchemy. Any insights or suggestions would be greatly appreciated!