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Social Media Backend

Social Media Backend

Welcome to the Social Media Backend! This is the backend API for the Social Media Full Stack App. It is built with Node.js and Express.js, and uses PostgreSQL for storing user data, posts, and other social features.

🛠️ Technologies Used

• Node.js – A JavaScript runtime for the server.
• Express.js – A web framework for Node.js.
• PostgreSQL – Relational database for storing user data and posts.
• Sequelize – SQL ORM for Node.js with PostgreSQL support.
• JWT (JSON Web Token) – For user authentication and authorization.
• Bcrypt.js – For hashing user passwords.
• Multer – For handling file uploads (profile pictures, post images).
• Helmet – For security headers and CORS configuration.

🚀 Features

• User Authentication: Secure login and registration with JWT.
• Post Management: Create, view, update, and delete posts.
• User Profile: Store and update user profile information.
• Follow/Unfollow System: Users can follow and unfollow each other.
• Like/Unlike Posts: Interactive engagement with posts.
• Timeline Feed: View posts from followed users.
• Image Upload: Profile pictures, cover photos, and post images.
• CORS Support: Configured to accept requests from the frontend.

📦 Installation & Setup

Prerequisites

• Node.js (v14 or higher)
• PostgreSQL (v12 or higher)
• npm or yarn

1. Install PostgreSQL

Download and install from: https://www.postgresql.org/download/

2. Create Database

psql -U postgres
CREATE DATABASE socialmedia_db;
\q

3. Install Dependencies

cd Social-Media-Backend
npm install

4. Configure Environment Variables

Create a .env file:

DB_NAME=socialmedia_db
DB_USER=postgres
DB_PASSWORD=your_password_here
DB_HOST=localhost
DB_PORT=5432

PORT=8800
JWT_SECRET=your_jwt_secret_key

5. Run the Server

npm start

Expected output:

✅ PostgreSQL connection established successfully
✅ Database synchronized successfully
Server is running on port 8800

📚 API Endpoints

Authentication

• POST /api/auth/register - Register new user
• POST /api/auth/login - Login user

Users

• GET /api/users?userId=1 - Get user by ID
• GET /api/users?username=john - Get user by username
• PUT /api/users/:id - Update user
• DELETE /api/users/:id - Delete user
• PUT /api/users/:id/follow - Follow user
• PUT /api/users/:id/unfollow - Unfollow user
• GET /api/users/friends/:userId - Get user's friends

Posts

• POST /api/posts - Create post
• GET /api/posts/:id - Get post by ID
• PUT /api/posts/:id - Update post
• DELETE /api/posts/:id - Delete post
• PUT /api/posts/:id/like - Like/unlike post
• GET /api/posts/timeline/all/:userId - Get timeline feed
• GET /api/posts/profile/:username - Get user's posts

File Upload

• POST /api/upload - Upload image (profile/post)

🗄️ Database Schema

Users Table

• id - INTEGER (Primary Key, Auto Increment)
• username - VARCHAR(20) UNIQUE
• email - VARCHAR(50) UNIQUE
• password - VARCHAR (hashed)
• profilePicture - VARCHAR
• coverPicture - VARCHAR
• followers - INTEGER[] (array)
• followings - INTEGER[] (array)
• isAdmin - BOOLEAN
• desc - VARCHAR(50)
• createdAt - TIMESTAMP
• updatedAt - TIMESTAMP

Posts Table

• id - INTEGER (Primary Key, Auto Increment)
• userId - INTEGER (Foreign Key → users.id)
• desc - TEXT
• img - VARCHAR
• likes - INTEGER[] (array)
• dislikes - INTEGER[] (array)
• comments - JSON[] (array)
• createdAt - TIMESTAMP
• updatedAt - TIMESTAMP

📖 Documentation

For detailed migration and setup information, see:

• POSTGRES_MIGRATION_GUIDE.md - Complete migration guide
• POSTGRESQL_SETUP_INSTRUCTIONS.md - Setup and troubleshooting
• SEQUELIZE_QUICK_REFERENCE.md - Query reference
• BEFORE_AFTER_COMPARISON.md - Code comparisons
• MIGRATION_COMPLETE.md - Migration summary

🌐 Live Demo

Frontend: https://social-med-007.netlify.app

🔒 Security Features

• Password hashing with bcrypt (10 salt rounds)
• JWT token-based authentication
• Helmet security headers
• CORS configuration
• SQL injection prevention via Sequelize
• Foreign key constraints

🚀 Deployment

Render / Heroku

1. Add PostgreSQL database service
2. Set environment variables (DATABASE_URL)
3. Deploy from GitHub repository

Environment Variables for Production

DATABASE_URL=postgresql://user:password@host:5432/dbname
PORT=8800
JWT_SECRET=secure_random_string

📝 Migration from MongoDB

This project was recently migrated from MongoDB to PostgreSQL for:

• ✅ Better performance on complex queries
• ✅ ACID compliance and data integrity
• ✅ Foreign key relationships
• ✅ Industry-standard SQL database

See POSTGRES_MIGRATION_GUIDE.md for details.

🤝 Contributing

Feel free to fork this repository and submit pull requests!

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Built with ❤️ using Node.js, Express, and PostgreSQL