RT-Chat API

This project is an API built in Java using the Spring Boot framework. It serves as the backend for the RT-Chat Frontend project, providing real-time chat functionalities.

Core Technologies:

• Framework: Java 17, Spring Boot 3
• Database: PostgreSQL
• Authentication: Spring Security & JSON Web Tokens (JWT)
• Real-time Communication: WebSocket (STOMP)
• API Documentation: Swagger/OpenAPI
• Unit Tests: JUnit & Mockito
• Integration Tests: Spring Boot Test

Table of Contents

• Prerequisites
• Installation
• Configuration
• Running the application
• Authentication Flow
• API Endpoints Overview
• WebSocket Communication
• Database Schema

Prerequisites

Before starting, ensure you have the following tools installed on your system:

• Java 17 or higher
• Apache Maven 3.6 or later.
• PostgreSQL server running locally or accessible remotely.

Installation

1. Clone the repository:

git clone https://github.com/jmfs12/rt-chat-api.git
cd rt-chat-api

2. Install dependencies with Maven

mvn clean install

Configuration

Application settings are managed in src/main/resources/application.properties. Before running the application, you must configure the database connection and JWT settings.

1. Database configuration

   • Set up your PostgreSQL database and update the following properties in application.properties:

   spring.datasource.url=jdbc:postgresql://localhost:5432/your_database
   spring.datasource.username=your_username
   spring.datasource.password=your_password
   spring.jpa.hibernate.ddl-auto=update
   spring.jpa.show-sql=true
   spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect

2. JWT Secret Configuration

   • Set a secure secret key for JWT in the application properties:

   # JWT Configuration
   # Use a strong base64 encoded secret key for production environments.
   jwt.secret.key=YOUR_ULTRA_SECRET_KEY_FOR_JWT_SIGNING
   jwt.expiration.ms=86400000 # Token expiration time in milliseconds (e.g., 24 hours)

Running the application

Once configured, start the application using the Spring Boot Maven plugin:

mvn spring-boot:run

The Api will be accessible at http://localhost:8080.

Api Documentation (Swagger):

API documentation is available at http://localhost:8080/swagger-ui.html once the application is running.

Authentication Flow

Authentication is handled using JWT. Access to protected endpoints requires a valid token provided in the Authorization header.

1. Registration: Users can register by sending a POST request to /api/auth/register with their details.
2. Login: The user authenticates using credentials via the POST /api/auth/login endpoint.
3. Token Generation: Upon successful authentication, a JWT is generated and returned to the client.
4. Token Usage: The client includes the JWT in the Authorization header for subsequent requests to protected endpoints.

API Endpoints Overview

• Authentication:
  • POST /api/auth/register: Register a new user.
  • POST /api/auth/login: Authenticate and receive a JWT.
• User Management:
  • GET /api/users: Retrieve a list of users (protected).
  • GET /api/users/me: Get current user details by ID (protected).
• Message Management:
  • GET /api/messages: Get all messages between two users.

WebSocket Communication

Real-time messaging is implemented using WebSocket with STOMP protocol.

• WebSocket Endpoint: ws://localhost:8080/ws
• User-Specific Notifications (Private Messages/Updates): Clients subscribe to their private queue to receive direct messages and notifications.
  • Subscribe: /user/queue/message

Database Schema

The database schema is managed by Spring Data JPA based on the entity classes defined in the source code. The primary entities include:

• User: Represents application users with fields for username, password, email, and roles.
• Message: Represents chat messages with fields for sender, receiver, content, and timestamp

Contributing

Contributions are welcome! Please fork the repository and create a pull request with your changes.