Chat App

A modern real-time chat application built with React, Node.js, Express, MongoDB, and Socket.IO.
The app features real-time messaging, user authentication, profile management, and a responsive UI.

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Deployed Applications

• Frontend (Vercel): Chat App Frontend
• Backend (Render): Chat App Backend

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Features

Frontend

• Real-time messaging interface
• Responsive design for all devices
• Secure user authentication and session management
• Profile editing and user search functionality
• Loading indicators and smooth UX transitions

Backend

• User registration and login (JWT + secure cookies)
• Email existence checking
• Profile update and user search APIs
• Secure password hashing using bcryptjs
• Real-time communication with Socket.IO
• MongoDB database for persistent storage

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Technologies Used

• Frontend: React, Redux, Socket.IO Client
• Backend: Node.js, Express.js, MongoDB, Mongoose, Socket.IO, JWT, bcryptjs
• Deployment: Vercel (Frontend), Render (Backend)

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Frontend Folder Structure

client/
├── public/
│   └── static assets (favicon, manifest, etc.)
├── src/
│   ├── assets/ (audio, videos, images)
│   ├── components/ (UI components like Avatar, SearchUser, Sidebar)
│   ├── helper/ (helper functions like uploadFile.js)
│   ├── layout/ (application layouts)
│   ├── pages/ (major pages like Home, Register, ForgotPassword)
│   ├── redux/ (store and userSlice)
│   ├── routers/ (application routing)
│   ├── App.js / App.css / index.js
├── .env
├── package.json
└── README.md

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Backend Folder Structure

server/
├── config/ (MongoDB connection setup)
├── controller/ (request handlers: register, login, logout, update user)
├── helpers/ (utility functions)
├── models/ (Mongoose models for User and Conversation)
├── routes/ (API routes)
├── socket/ (Socket.IO server handling)
├── .env
├── index.js
└── README.md

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API Endpoints

Method	Endpoint	Description
POST	/api/register	Register a new user
POST	/api/email	Check if email exists
POST	/api/password	Authenticate user, set cookie
GET	/api/user-details	Fetch current user details
GET	/api/logout	Logout user, clear session
POST	/api/update-user	Update user profile
POST	/api/search-user	Search users by name or email

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Real-time Messaging

• Authenticated Socket.IO connections using JWT tokens.
• Event-driven architecture for sending and receiving messages.
• Conversations are saved in MongoDB for persistence.

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Getting Started (Local Development)

Prerequisites

• Node.js (v14 or newer)
• npm (v6 or newer)
• MongoDB (local or Atlas)

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Frontend Setup

1. Navigate to the client folder:

   cd client

2. Install dependencies:

   npm install

3. Run the app:

   npm start

   Access it at: http://localhost:3000

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Backend Setup

1. Navigate to the server folder:

   cd server

2. Install dependencies:

   npm install

3. Create a .env file in the /server directory:

   FRONTEND_URL=http://localhost:3000
   MONGO_URI=your-mongodb-uri
   PORT=8080
   JWT_SECRET_KEY=your-secret-key
   

4. Run the server:

   npm start
   # or
   node index.js

   Backend will run on http://localhost:8080

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Environment Variables

Variable	Purpose
FRONTEND_URL	URL of frontend (for CORS)
MONGO_URI	MongoDB connection string
PORT	Port for server (default 8080)
JWT_SECRET_KEY	Secret key for JWT token encryption

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Available Scripts

Command	Usage
npm start	Run development server (client or server)
npm run build	Build production frontend assets
npm test	Run frontend tests
npm run eject	Eject CRA configuration (irreversible)

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Deployment Notes

• Frontend and backend must be served over HTTPS in production.
• Configure cookies with SameSite=None; Secure for cross-site authentication.
• Update .env variables before deploying to Vercel and Render.

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Learn More

• React Documentation
• Create React App Docs
• Express.js Documentation
• MongoDB Documentation
• Socket.IO Documentation

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License

This project is licensed under the MIT License.

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