👀 Views: 56 💬 Answers: 1 📅 Created: 2025-06-04

fastapi asyncio background-tasks Python

I'm sure I'm missing something obvious here, but I'm working on a personal project and I'm building a FastAPI application that requires me to run some background tasks asynchronously after a user submits a request..... However, I'm working with an scenario where my async function seems to be returning `None`, causing my application to unexpected result silently without any behavior messages. Here's a simplified version of my code: ```python from fastapi import FastAPI, BackgroundTasks import time app = FastAPI() def background_task(name: str): time.sleep(5) # Simulating a long-running task print(f"Task completed for {name}") @app.post("/submit/") async def submit_item(name: str, background_tasks: BackgroundTasks): background_tasks.add_task(background_task, name) return {"message": "Request received and task started."} ``` When I hit the `/submit/` endpoint with a POST request, I get the expected message, but nothing is printed afterward, and it seems like the background task isn't running as intended. I've checked my FastAPI version, which is 0.68.0, and I'm using Uvicorn as my ASGI server. I've tried adding logging to see if the background task is even being called, but that doesn't seem to give me any output either. Am I missing something in the async context or the way I'm registering the background task? Any pointers would be greatly appreciated! Am I missing something obvious? Has anyone else encountered this?