Cookie-based request rate limiting in JavaScript

24 Sep 2023

ratelimiting

Request rate limiting is an important technique used to protect web applications from abuse and ensure fair resource allocation. One way to implement request rate limiting is by using cookies in JavaScript. In this blog post, we will explore how to implement cookie-based request rate limiting in JavaScript.

Cookie-based request rate limiting is a technique where a server sets a cookie on the client’s browser to track the number of requests made by the client within a certain time frame. The server can then check the value of the cookie for each subsequent request to enforce a rate limit.

To implement cookie-based request rate limiting in JavaScript, we can follow these steps:

Set a cookie with an initial value of 0 when the client makes the first request.
```
document.cookie = "requestCount=0; path=/";
```

On subsequent requests, check the value of the cookie and compare it with the maximum allowed requests within the time frame.

function checkRequestLimit() {
  var requestCount = parseInt(getCookie("requestCount"));
  var maxRequests = 100;
  var timeFrame = 60; // in seconds

  if (requestCount >= maxRequests) {
    // Exceeds rate limit, handle accordingly
    return false;
  }

  // Update the cookie with the incremented value
  document.cookie = "requestCount=" + (requestCount + 1) + "; path=/";
  return true;
}

function getCookie(name) {
  var cookieArr = document.cookie.split(";");

  for (var i = 0; i < cookieArr.length; i++) {
    var cookiePair = cookieArr[i].split("=");

    if (name == cookiePair[0].trim()) {
      return cookiePair[1];
    }
  }

  return null;
}

Call the checkRequestLimit function before making each request and handle the response accordingly.

if (checkRequestLimit()) {
  // Make the request
  // ...
} else {
  // Handle rate limit exceeded
  // ...
}

Simple implementation: Implementing cookie-based request rate limiting in JavaScript is relatively simple and doesn’t require server-side modifications.
Client-side control: The rate limiting logic is executed on the client-side, reducing the server’s processing load.
Effective for non-authenticated users: Cookie-based rate limiting is effective for non-authenticated users as it doesn’t depend on user-specific information.

Conclusion

Cookie-based request rate limiting in JavaScript is an effective technique to protect web applications from abuse and ensure fair resource allocation. By setting cookies and tracking request counts, we can enforce rate limits on clients. Remember to adjust the maxRequests and timeFrame variables according to your specific requirements. Additionally, keep in mind that cookie-based rate limiting is not foolproof and should be supplemented with other security measures for comprehensive protection.

#javascript #ratelimiting

What is cookie-based request rate limiting?

Implementing cookie-based request rate limiting

Benefits of cookie-based request rate limiting

Conclusion