Dhruv gupta week4 assignment

week-4/middlewares/01-ratelimitter.js

@@ -1,27 +1,40 @@
-// You have to create a middleware for rate limiting a users request based on their username passed in the header
-
 const express = require('express');
 const app = express();
 
-// Your task is to create a global middleware (app.use) which will
-// rate limit the requests from a user to only 5 request per second
-// If a user sends more than 5 requests in a single second, the server
-// should block them with a 404.
-// User will be sending in their user id in the header as 'user-id'
-// You have been given a numberOfRequestsForUser object to start off with which
-// clears every one second
-
 let numberOfRequestsForUser = {};
+
+// Clears the request count for each user every second
 setInterval(() => {
     numberOfRequestsForUser = {};
-}, 1000)
+}, 1000);
+
+// Rate limiting middleware
+app.use((req, res, next) => {
+    const userId = req.headers['user-id'];
+
+    if (!userId) {
+        return res.status(400).json({ error: 'User ID missing in headers' });
+    }
+
+    if (!numberOfRequestsForUser[userId]) {
+        numberOfRequestsForUser[userId] = 0;
+    }
+
+    numberOfRequestsForUser[userId]++;
+
+    if (numberOfRequestsForUser[userId] > 5) {
+        return res.status(404).json({ error: 'Too many requests' });
+    }
+
+    next();
+});
 
-app.get('/user', function(req, res) {
-  res.status(200).json({ name: 'john' });
+app.get('/user', (req, res) => {
+    res.status(200).json({ name: 'john' });
 });
 
-app.post('/user', function(req, res) {
-  res.status(200).json({ msg: 'created dummy user' });
+app.post('/user', (req, res) => {
+    res.status(200).json({ msg: 'created dummy user' });
 });
 
-module.exports = app;
+module.exports = app;

week-4/middlewares/package.json

@@ -10,7 +10,7 @@
   "license": "ISC",
   "description": "",
   "dependencies": {
-    "express": "^4.18.2"
+    "express": "^4.20.0"
   },
   "devDependencies": {
     "@babel/plugin-transform-modules-commonjs": "^7.23.3",

week-5/backend/index.js

@@ -1 +1,15 @@
-// start writing from here
+const express = require("express");
+const jwt = require("jsonwebtoken");
+const userRoutes = require("./routes/user"); // Import the routes from user.js
+const todoRoutes = require("./routes/todo"); 
+
+const app = express();
+
+app.use(express.json());
+
+app.use("/users", userRoutes); // Use the routes defined in user.js
+app.use("/todos", todoRoutes); // Register the todo routes
+
+app.listen(3000, () => {
+    console.log("Server is running on port 3000");
+});

week-5/backend/middleware/user.js

@@ -1 +1,35 @@
-//  start writing from here
+const express = require("express");
+const jwt = require("jsonwebtoken");
+const { route } = require("../routes/user");
+
+const JWT_SECRET = "namaste"; 
+
+// Middleware function for authentication
+function auth(req, res, next) {
+    console.log("Auth middleware is being called"); // Log to check if middleware is called
+
+    const token = req.header("token");
+
+    if (!token) {
+        return res.status(401).json({
+            message: "Access Denied. No token provided."
+        });
+    }
+
+    try {
+        const decodedData = jwt.verify(token, JWT_SECRET);
+        req.username = decodedData.username; // Pass the username to the next middleware
+        console.log("Token is valid. Username:", req.username); // Log the decoded username
+        next(); // Continue to the next middleware/route handler
+    } catch (error) {
+        console.log("Token is invalid");
+        res.status(400).json({
+            message: "Invalid token"
+        });
+    }
+}
+
+
+
+
+module.exports = auth; // Export the auth middleware