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Jayvee Ramos
Jayvee Ramos

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Dynamic rate-limiting middleware in Express

#node #javascript #express #expressratelimit

To create a dynamic rate-limiting middleware in Express that can be used at different levels (controller, app, router), you can use the express-rate-limit package. This middleware can be configured dynamically based on the parameters you pass.

Here's an example of a custom rate-limiting middleware that can be used at different levels in Express:

First, install the express-rate-limit package:

npm install express-rate-limit
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Then, create a module that exports a function to generate the rate-limiting middleware dynamically:

// rateLimitMiddleware.js const rateLimit = require("express-rate-limit"); function createRateLimitMiddleware(options) { // You can configure the rate limit dynamically using the options parameter const limiter = rateLimit({ windowMs: options.windowMs || 60 * 1000, // 1 minute by default max: options.max || 100, // 100 requests per windowMs by default message: options.message || "Too many requests, please try again later." }); return limiter; } module.exports = createRateLimitMiddleware;
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Next, in your Express application, you can use this dynamically created rate-limiting middleware in different levels:

At the App Level: 

const express = require("express"); const app = express(); const createRateLimitMiddleware = require("./rateLimitMiddleware"); // Apply rate limiting for the entire app const appLevelRateLimiter = createRateLimitMiddleware({ windowMs: 60 * 60 * 1000, // 1 hour max: 1000, // 1000 requests per hour }); app.use(appLevelRateLimiter); // Other app configurations and routes
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At the Router/Route Level: 

const express = require("express"); const router = express.Router(); const createRateLimitMiddleware = require("./rateLimitMiddleware"); // Apply rate limiting for a specific router const routerLevelRateLimiter = createRateLimitMiddleware({ windowMs: 60 * 1000, // 1 minute max: 30, // 30 requests per minute }); router.use(routerLevelRateLimiter); // Define router paths and their respective handlers
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At the Controller Level (per route): 

const express = require("express"); const router = express.Router(); const createRateLimitMiddleware = require("./rateLimitMiddleware"); // Apply rate limiting for specific routes/controllers const specificRouteRateLimiter = createRateLimitMiddleware({ windowMs: 60 * 1000, // 1 minute max: 10, // 10 requests per minute }); router.get("/specific-route", specificRouteRateLimiter, (req, res) => { // Controller logic for the specific route });
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This setup allows you to dynamically configure rate-limiting based on your specific needs at different levels within your Express application. Adjust the parameters in the options object passed to createRateLimitMiddleware to fit your requirements.

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