Implementing Rate Limiting in Flask with Redis but Getting Unexpected 429 Response
I've looked through the documentation and I'm still confused about I've encountered a strange issue with I'm confused about I'm trying to implement rate limiting in my Flask application using Redis to store the request counts, but I'm working with an unexpected behavior where my API returns a 429 Too Many Requests response even when I believe I'm below the defined limits. I am using Flask version 2.1.1 and Flask-Limiter version 2.5.0. Here's how I have set up the rate limiting: ```python from flask import Flask, request from flask_limiter import Limiter from flask_limiter.util import get_remote_address import redis app = Flask(__name__) redis_server = redis.StrictRedis(host='localhost', port=6379, db=0) limiter = Limiter(key_func=get_remote_address, storage_uri='redis://localhost:6379') @limiter.limit('5 per minute') @app.route('/api/resource', methods=['GET']) def get_resource(): return "Success" ``` I have verified that the Redis server is running and able to accept connections. However, when I send more than 5 requests within a minute from the same IP, I do get a 429 response, but even when I send exactly 5 requests in that timeframe, I sometimes receive this behavior. I've added logging to track the counts and they seem correct: ```python @limiter.limit('5 per minute') @app.route('/api/resource', methods=['GET']) def get_resource(): current_count = limiter.check_request(get_remote_address()) app.logger.info(f'Current request count: {current_count}') return "Success" ``` Despite this, I still experience the 429 behavior intermittently. I've tried adjusting the rate limit to 10 per minute but the scenario continues. I also checked the Redis data directly, and it appears that some counts are not being reset as expected. Any insights into what might be causing this scenario? Are there any best practices I might have missed in handling rate limits with Flask-Limiter and Redis? For context: I'm using Python on Windows. What am I doing wrong? I'm using Python stable in this project. I'm on Linux using the latest version of Python. What's the best practice here?