How to implement rate limiting in a Python FastAPI REST API?
I tried several approaches but none seem to work. This might be a silly question, but Currently developing a REST API using FastAPI for a client project, and I want to ensure that we implement rate limiting to protect our endpoints from abuse... I've done some research and found a few different libraries like `slowapi` and `fastapi-limiter`. However, I’m unsure which one would be the best fit for a production environment. I’ve tried setting up `slowapi` as follows: ```python from slowapi import Limiter from fastapi import FastAPI limiter = Limiter(key_func=lambda request: request.client.host) app = FastAPI() @app.get("/items") @limiter.limit("5/minute") def read_items(): return {"message": "This is a rate-limited endpoint."} ``` This code seems straightforward, but I’m worried about how it behaves under a high load where multiple clients are hitting the endpoint simultaneously. Additionally, I’ve noticed that the `slowapi` documentation mentions that it defaults to in-memory storage for rate limit data, which seems risky for a distributed application. I’ve also explored `fastapi-limiter`, which uses Redis for storage, making it potentially more suitable for our architecture. I attempted to set it up like this: ```python from fastapi import FastAPI from fastapi_limiter import FastAPILimiter app = FastAPI() @app.on_event("startup") async def startup(): await FastAPILimiter.init() @app.get("/data") @limiter.limit("10/minute") def get_data(): return {"data": "This endpoint is limited!"} ``` However, I ran into an issue while trying to configure the Redis connection, receiving a `ConnectionError` stating that it couldn't connect to the Redis server. For context, we’re using Docker to run our services, and the Redis container is set up in the same network. Here's part of my `docker-compose.yml`: ```yaml version: '3' services: redis: image: redis:latest ports: - "6379:6379" api: build: context: . depends_on: - redis networks: - app-network networks: app-network: driver: bridge ``` Can someone provide insight into how to effectively implement rate limiting with FastAPI? Should I stick with `slowapi`, or is `fastapi-limiter` the better choice? Also, what configurations should I check to resolve the connection issues with Redis? Any tips or best practices for a robust rate limiting setup would be appreciated. I'm working on a web app that needs to handle this. Has anyone else encountered this? I'm using Python stable in this project. What's the best practice here?