GraphQL Real-Time Chat App (Node.js, Express, PostgreSQL, Prisma, GraphQL, WebSockets)

🚀 Project Overview

This is a real-time chat application backend built using GraphQL, Apollo Server, Express, PostgreSQL, Prisma ORM, and WebSockets for real-time messaging.

🏗️ Project Structure

/graphql-chat-backend
│── src/
│   ├── schema/
│   │   ├── message.js    # GraphQL Type Definitions
│   ├── resolvers/
│   │   ├── message.js    # Message Resolvers
│   │   ├── auth.js       # Authentication Logic
│   ├── middleware/
│   │   ├── authMiddleware.js # JWT Authentication Middleware
│   ├── utils/
│   │   ├── jwt.js        # JWT Helper Functions
│   ├── prisma/
│   │   ├── schema.prisma # Prisma Database Schema
│   ├── index.js          # Server Entry Point
│── .env                  # Environment Variables
│── package.json          # Dependencies
│── prisma/migrations/    # Prisma Migrations

📦 Installation

1️⃣ Clone the Repository

git clone https://github.com/your-repo/graphql-chat-backend.git
cd graphql-chat-backend

2️⃣ Install Dependencies

npm install

3️⃣ Configure Environment Variables

Create a .env file in the root directory:

DATABASE_URL=postgresql://user:password@localhost:5432/chatdb
JWT_SECRET=your_secure_jwt_secret
PORT=4000

4️⃣ Set Up Database

Make sure you have PostgreSQL installed and running. Then, run:

npx prisma migrate dev --name init
npx prisma generate

This initializes the database with required tables.

5️⃣ Start the Server

npm start

Your GraphQL API is now running at:
🌍 http://localhost:4000/graphql
⚡ WebSockets active at ws://localhost:4000/graphql

---

🔥 Features Implemented

• User Authentication (JWT)
• Real-time Messaging with WebSockets
• GraphQL Queries, Mutations, and Subscriptions
• Prisma ORM for Database Management
• Express Middleware for Authentication
• PostgreSQL Database Integration

---

📜 GraphQL Schema

type Message {
  id: ID!
  senderId: String!
  content: String!
  timestamp: String!
}

type User {
  id: ID!
  username: String!
  email: String!
  password: String!
}

type Query {
  messages: [Message]
}

type Mutation {
  createUser(username: String!, email: String!, password: String!): User!
  sendMessage(senderId: String!, content: String!): Message
}

type Subscription {
  messageSent: Message
}

---

🗄 Database Schema

The database structure using Prisma ORM:

model User {
  id       String   @id @default(uuid())
  username String   @unique
  email    String   @unique
  password String
  messages Message[]
}

model Message {
  id        String   @id @default(uuid())
  sender    User     @relation(fields: [senderId], references: [id])
  senderId  String
  content   String
  timestamp DateTime @default(now())
}

---

📡 API Endpoints (GraphQL)

1️⃣ Create a User

mutation {
  createUser(username: "Alice", email: "alice@email.com", password: "securepass") {
    id
    username
    email
  }
}

2️⃣ Authenticate & Get JWT Token

mutation {
  login(email: "alice@email.com", password: "securepass") {
    token
  }
}

3️⃣ Send a Message

mutation {
  sendMessage(senderId: "user-id", content: "Hello, GraphQL!") {
    id
    content
    timestamp
  }
}

4️⃣ Get Messages

query {
  messages {
    id
    senderId
    content
    timestamp
  }
}

5️⃣ Subscribe to New Messages (Real-Time)

subscription {
  messageSent {
    id
    senderId
    content
    timestamp
  }
}

---

🛠️ Technologies Used

• Node.js + Express (Backend)
• GraphQL + Apollo Server (API)
• PostgreSQL (Database)
• Prisma ORM (Database Management)
• JWT Authentication (Security)
• WebSockets (GraphQL Subscriptions) (Real-Time Communication)
• Docker (Optional, for database setup)

---

🚀 Next Steps

• ✅ Complete Authentication (✔️ Done!)
• ✅ Setup WebSocket for Real-Time Messages (✔️ Done!)
• 🔜 Build Flutter Frontend
• 🔜 Improve Message Filtering & Pagination
• 🔜 Deploy to Production (Docker, AWS, or Heroku)

---

📜 License

This project is open-source and free to use under the MIT License.

---

👨‍💻 Contributors

• Jude - Backend Developer

For issues, feel free to open an issue or contribute! 🚀