Rate Limiting (速率限制) Tutorial

Rate limiting is a crucial concept in web development to ensure the stability and reliability of your application. It helps in preventing abuse, managing server load, and maintaining a good user experience.

What is Rate Limiting?

Rate limiting is the practice of controlling the rate at which requests are sent to a server. It is essential for protecting your application from being overwhelmed by too many requests in a short period of time.

Key Benefits of Rate Limiting:

Prevent Abuse: Limit the number of requests from a single user to avoid brute force attacks.
Server Protection: Reduce server load by managing the number of requests.
Maintain Performance: Ensure that your application remains responsive and accessible to all users.

Implementing Rate Limiting

Implementing rate limiting involves setting up rules and thresholds to control the number of requests per user or IP address. Here are some common strategies:

Fixed Window Rate Limiting: Track the number of requests within a fixed time window.
Sliding Window Rate Limiting: Track the number of requests within a sliding window.
Token Bucket: Allocate a certain number of tokens for each user, and consume tokens with each request.

Configuration Example

Here's a simple example of configuring rate limiting in an application:

app.use(rateLimit({
  windowMs: 15 * 60 * 1000, // 15 minutes
  max: 100 // limit each IP to 100 requests per windowMs
}));

For more detailed configuration options and usage examples, please refer to the Rate Limiting Configuration Guide.

Best Practices

Monitor and Adjust: Continuously monitor the performance of your rate limiting strategy and adjust thresholds as needed.
Graceful Handling: Implement proper error handling and feedback for users who exceed their rate limits.
Documentation: Clearly document your rate limiting policy for users and developers.