Node.Js Tutorial Development Tutorials, Guides & Insights

// rateLimiter.js
const client = require("./redisClient");

const rateLimiter = (limit = 100, windowSec = 3600) => {
  return async (req, res, next) => {
    const ip = req.ip;
    const key = `rate_limit:${ip}`;

    const current = await client.get(key);

    if (current !== null && parseInt(current) >= limit) {
      return res.status(429).json({ error: "Too many requests. Try later." });
    }

    const multi = client.multi();
    multi.incr(key);
    if (!current) {
      multi.expire(key, windowSec);
    }
    await multi.exec();

    next();
  };
};

module.exports = rateLimiter;

// server.js
require("dotenv").config();
const express = require("express");
const rateLimiter = require("./rateLimiter");

const app = express();
const PORT = 3000;

app.use(rateLimiter(100, 3600)); // 100 requests/hour per IP

app.get("/", (req, res) => {
  res.send("Welcome! You're within rate limit.");
});

app.listen(PORT, () => {
  console.log(`Server running on http://localhost:${PORT}`);
});

• Run JavaScript Anywhere: Execute code on your computer, independent of the browser.
• Server-Side Development: Build APIs and back-end services.
• Access to npm: Use and manage libraries and tools through the Node Package Manager (npm).

• Visit the official Node.js website.
• Download the LTS (Long Term Support) version for better stability.

npm install sqlite3

> Note: If you encounter issues during installation, especially on Windows, ensure you have the necessary build tools. You might need to install Windows Build Tools or use the --build-from-source flag.

This command adds the NodeSource repository to your system, allowing you to install newer versions of Node.js.

Once the repository is added, install Node.js: