Background Tasks and Job Queues
Learn to offload slow work from request handlers using FastAPI background tasks and distributed job queues like Celery.
Why Offload Work?
Some work, like sending email, generating reports, or processing images, is too slow to do inside a request.
Making the user wait hurts latency. Instead, respond fast and do the heavy work in the background.
FastAPI BackgroundTasks
FastAPI ships a lightweight BackgroundTasks tool for work that should run after the response is sent.
from fastapi import BackgroundTasks
def write_log(msg: str):
with open("log.txt", "a") as f:
f.write(msg)
@app.post("/signup")
def signup(bg: BackgroundTasks):
bg.add_task(write_log, "new user")
return {"ok": True}All lessons in this course
- Caching Strategies with Redis
- Asynchronous Database Access
- Load Balancing & Monitoring
- Background Tasks and Job Queues