🐦 Twitter Clone Backend (Node.js + Express + MongoDB)

This is the backend API for a Twitter-style full-stack application, built with Node.js, Express, and MongoDB, designed for job application and demo purposes. It supports user authentication, post creation, likes, comments, following, notifications, search, and profile updates — all with a modular and scalable architecture.

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🚀 Features

✅ Core Functionality

• 🔐 User authentication (JWT + cookies)
• 👤 Profile management
• 📝 Create, update, delete posts
• 💬 Comment on posts
• ❤️ Like/unlike system
• 🔔 In-app notifications
• 🤝 Follow/unfollow users
• 🔍 Search users
• 🧠 Suggested users
• 📄 Pagination + filtering (via reusable helpers)

🧰 Tech Stack

• Node.js + Express
• MongoDB + Mongoose
• Joi for request validation
• Cloudinary for image uploads
• CORS + Helmet + Rate Limiting for security

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🧑‍💻 Project Structure

twitter-clone-backend/
│
├── controllers/       # Route logic
├── routes/            # API endpoints
├── models/            # Mongoose schemas
├── middlewares/       # Auth, error, validators
├── validations/       # Joi schemas
├── modules/           # Helpers like ModelQuery, CustomError
├── utils/             # Cloudinary, sanitization, etc.
├── app.js             # Express config and middleware setup
├── server.js          # App entry (connect DB, start server)
└── .env               # Environment config

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🔐 Security

• JWT + cookies for authentication
• CORS with credentials
• Helmet for secure headers
• Rate limiting
• MongoDB & XSS sanitization

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🔗 Frontend

The frontend of this app is available at:
👉 twitter-clone-client Repo

📸 Postman API Screenshot

🌍 Live Demo

https://twitter-clone-backend-f6w8.onrender.com/

⚙️ Environment Variables

Create a .env file in the root:

PORT=5000
MONGO_URI=your-mongodb-uri
JWT_SECRET=your-jwt-secret
CLIENT_URL=http://localhost:3000
CLOUDINARY_CLOUD_NAME=your-cloud-name
CLOUDINARY_API_KEY=your-api-key
CLOUDINARY_API_SECRET=your-api-secret
NODE_ENV=development

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🔗 Key API Endpoints

Endpoint	Description
POST /api/auth/register	Register a new user
POST /api/auth/login	Login user
GET /api/users/profile/:username	Get public profile
PATCH /api/users/profile/:username	Update profile
GET /api/posts	Get all posts (paginated)
POST /api/posts	Create a new post
GET /api/users/profile/:username/posts	User's posts
GET /api/users/profile/:username/likes	Liked posts
POST /api/posts/:id/comments	Add comment to post
PATCH /api/users/follow/:id	Follow/unfollow user
GET /api/users/search?search=	Search users
GET /api/users/suggestions/all	Suggested users (paginated)

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📦 Running Locally

git clone https://github.com/your-username/twitter-clone-backend.git
cd twitter-clone-backend
npm install
npm run dev

Runs at http://localhost:5000

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🧪 Testing

Use Postman or Insomnia:

• Pass JWT token via cookie or Authorization header.
• Most routes require authentication (protectRoute middleware).

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🌍 Deployment

This backend is production-ready. Host the frontend separately (e.g. on Vercel), and the backend on services like:

• Render
• Railway
• Fly.io
• DigitalOcean App Platform

CORS is preconfigured to support frontend-backend separation (credentials: true).

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✨ Highlights

• Reusable ModelQuery for clean pagination/search
• Joi for strong request validation
• Cloudinary upload/delete integration
• Fully separated backend ready to pair with any frontend (e.g. React + TanStack Query)

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📝 License

MIT — Feel free to use for job applications, portfolios, and learning.