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week-3/02-course-app-easy-2/index.js

@@ -1,4 +1,5 @@
 const express = require('express');
+const jwt = require('jsonwebtoken');
 const app = express();
 
 app.use(express.json());
@@ -7,46 +8,169 @@ let ADMINS = [];
 let USERS = [];
 let COURSES = [];
 
+const secretKey = "My-Secret-Key";
+
+const generateJwt = (user) => {
+  const payload = {username: user.username};
+  return jwt.sign(payload, secretKey, {expiresIn: '1h'});
+};
+
+const authenticateJwt = (req, res, next) => {
+  const authHeader = req.headers.authorization;
+
+  if(authHeader){
+    const token = authHeader.split(' ')[1];
+
+    jwt.verify(token, secretKey, (err, user) => {
+      if(err){
+        return res.status(403);
+      }
+
+      req.user = user;
+      next();
+    });
+  }
+
+  else{
+    res.status(401);
+  }
+};
+
 // Admin routes
 app.post('/admin/signup', (req, res) => {
   // logic to sign up admin
+  const admin = req.body;
+  const existingAdmin = ADMINS.find(a => a.username === admin.username);
+
+  if(existingAdmin){
+    res.status(403).json({message: 'Admin already exists'});
+  }
+
+  else{
+    ADMINS.push(admin);
+    const token = generateJwt(admin.username);
+    res.json({message: 'Admin created successfully', token});
+  }
 });
 
 app.post('/admin/login', (req, res) => {
   // logic to log in admin
+  const {username, password} = req.headers;
+  const admin = ADMINS.find(a => a.username === username && a.password === password);
+
+  if(admin){
+    const token = generateJwt(admin.username);
+    res.json({message: 'Logged in succcessfully', token});
+  }
+
+  else{
+    res.status(403).json({message: 'Admin authentication failed'});
+  }
 });
 
-app.post('/admin/courses', (req, res) => {
+app.post('/admin/courses', authenticateJwt, (req, res) => {
   // logic to create a course
+  const course = req.body;
+  course.id = COURSES.length + 1;
+  COURSES.push(course);
+  res.json({message: 'course created successfully', courseId: course.id});
 });
 
-app.put('/admin/courses/:courseId', (req, res) => {
+app.put('/admin/courses/:courseId', authenticateJwt, (req, res) => {
   // logic to edit a course
+  const courseId = parseInt(req.params.courseId);
+  const courseIndex = COURSES.findIndex(c => c.id === courseId);
+
+  if(courseIndex > -1){
+    const updatedCourse = { ...COURSES[courseIndex], ...req.body};
+    COURSES[courseIndex] = updatedCourse;
+    res.json({message: 'Course updated successfully'});
+  }
+
+  else{
+    res.status(404).json({message: 'Course not found'});
+  }
 });
 
 app.get('/admin/courses', (req, res) => {
   // logic to get all courses
+  res.json({courses: COURSES});
 });
 
 // User routes
 app.post('/users/signup', (req, res) => {
   // logic to sign up user
+  const user = req.body;
+  const existingUser = USERS.find(u => u.username === user.username);
+
+  if(existingUser){
+    res.status(403).json({message: 'User already exists'});
+  }
+
+  else{
+    USERS.push(user);
+    const token = generateJwt(user.username);
+    res.json({message: 'User created successfully'});
+  }
 });
 
 app.post('/users/login', (req, res) => {
   // logic to log in user
+  const {username, password} = req.headers;
+  const user = USERS.find(u => u.username === username && u.password === password);
+
+  if(user){
+    const token = generateJwt(user.username);
+    res.json({message: 'Logged in successfully'});
+  }
+
+  else{
+    res.status(403).json({message: 'User authentication failed'});
+  }
 });
 
-app.get('/users/courses', (req, res) => {
+app.get('/users/courses', authenticateJwt, (req, res) => {
   // logic to list all courses
+  res.json({courses: COURSES});
 });
 
-app.post('/users/courses/:courseId', (req, res) => {
+app.post('/users/courses/:courseId', authenticateJwt, (req, res) => {
   // logic to purchase a course
+  const courseId = parseInt(req.params.courseId);
+  const course = COURSES.find(c => c.id === courseId);
+
+  if(course){
+    const user = USERS.find(u => u.username === req.user.username);
+
+    if(user){
+      if(!user.purchasedCourses){
+        user.purchasedCourses = [];
+      }
+
+      user.purchasedCourses.push(course);
+      res.json({message: 'Course purchased successfully'});
+    }
+
+    else{
+      res.status(403).json({message: 'User not found'});
+    }
+  }
+
+  else{
+    res.status(404).json({message: 'Course not found'});
+  }
 });
 
-app.get('/users/purchasedCourses', (req, res) => {
+app.get('/users/purchasedCourses', authenticateJwt, (req, res) => {
   // logic to view purchased courses
+  const user = USERS.find(u => u.username === req.user.username);
+  if(user && user.purchasedCourses){
+    res.json({purchasedCourses: user.purchasedCourses});
+  }
+
+  else{
+    res.status(404).json({message: 'No courses purchased'});
+  }
 });
 
 app.listen(3000, () => {

week-3/02-course-app-easy/index.js

@@ -6,47 +6,151 @@ app.use(express.json());
 let ADMINS = [];
 let USERS = [];
 let COURSES = [];
+let userPurchases = [];
 
 // Admin routes
 app.post('/admin/signup', (req, res) => {
   // logic to sign up admin
+  var details = req.body;
+  var flag = false;
+
+  for(let i=0;i<ADMINS.length;i++){
+    if(details.username == ADMINS[i].username && details.password == ADMINS[i].password){
+      flag = true;
+      break;
+    }
+  }
+
+  if(flag){
+    res.status(404).json('Admin already exists');
+  }
+
+  else{
+    ADMINS.push(details);
+    res.status(200).json('Admin created successfully')
+  }
+
 });
 
 app.post('/admin/login', (req, res) => {
   // logic to log in admin
+  var usernameCheck = req.headers.username;
+  var passwordCheck = req.headers.password;
+  var flag = false;
+
+  for(let i=0;i<ADMINS.length;i++){
+    if(usernameCheck == ADMINS[i].username && passwordCheck == ADMINS[i].password){
+      flag = true;
+      break;
+    }
+  }
+
+  if(flag){
+    res.status(200).json('Logged in successfully');
+  }
+
+  else{
+    res.status(404).json('Login Failed!');
+  }
+
 });
 
 app.post('/admin/courses', (req, res) => {
   // logic to create a course
+  var courseDetails = req.body;
+  courseDetails.id = Date.now;
+
+  COURSES.push(courseDetails);
+  res.status(200).json('Course created successfully');
 });
 
 app.put('/admin/courses/:courseId', (req, res) => {
   // logic to edit a course
+  var cid = req.params.courseId;
+  var updatedDetails = req.body;
+
+  for(let i=0;i<COURSES.length;i++){
+    if(COURSES[i].id == cid){
+      COURSES[i] = updatedDetails;
+      break;
+    }
+  }
+
+  res.status(200).json('Course updated successfully');
 });
 
 app.get('/admin/courses', (req, res) => {
   // logic to get all courses
+  res.status(200).json(COURSES);
 });
 
 // User routes
 app.post('/users/signup', (req, res) => {
   // logic to sign up user
+  var userDetails = req.body;
+  var flag = false;
+
+  for(let i=0;i<USERS.length;i++){
+    if(USERS[i].username == userDetails.username && USERS[i].password == userDetails.password){
+      flag = true;
+      break;
+    }
+  }
+
+  if(flag){
+    res.status(404).json('User already exists');
+  }
+
+  else{
+    res.status(200).json('User created successfully');
+  }
 });
 
 app.post('/users/login', (req, res) => {
   // logic to log in user
+  var usernameCheck = req.headers.username;
+  var passwordCheck = req.headers.password;
+
+  var flag = false;
+
+  for(let i=0;i<USERS.length;i++){
+    if(USERS[i].username == usernameCheck && USERS[i].password == passwordCheck){
+      flag = true;
+      break;
+    }
+  }
+
+  if(!flag){
+    res.status(404).json('Login Failed!');
+  }
+
+  else{
+    res.status(200).json('Logged in successfully');
+  }
 });
 
 app.get('/users/courses', (req, res) => {
   // logic to list all courses
+  res.status(200).json(COURSES);
 });
 
 app.post('/users/courses/:courseId', (req, res) => {
   // logic to purchase a course
+  var idOfCourse = req.params.courseId;
+
+  for(let i=0;i<COURSES.length;i++){
+    if(COURSES[i].id == idOfCourse){
+      userPurchases.push(COURSES[i]);
+      break;
+    }
+  }
+
+  res.status(200).json('Course purchased successfully');
 });
 
 app.get('/users/purchasedCourses', (req, res) => {
   // logic to view purchased courses
+  res.status(200).json(userPurchases);
 });
 
 app.listen(3000, () => {