Library Management System

A modern microservices-based library management system built with Spring Boot, featuring separate services for user management, book catalog, and borrowing operations.

Architecture

The system consists of four main components:

• API Gateway (Port 8080) - Routes requests and provides a unified entry point
• Books Service (Port 8081) - Manages books and authors
• Borrowing Service (Port 8082) - Handles book borrowing operations
• Users Service (Port 8083) - Manages library users

Technology Stack

• Backend: Java 21, Spring Boot 3.5.5
• Database: PostgreSQL 15
• ORM: Spring Data JPA with Hibernate
• Database Migration: Liquibase
• Mapping: MapStruct
• Validation: Jakarta Bean Validation
• API Gateway: Spring Cloud Gateway
• Containerization: Docker & Docker Compose

Prerequisites

• Java 21+
• Maven 3.8+
• Docker & Docker Compose
• Git

Quick Start

1. Clone the Repository

  git clone <repository-url>
  cd example-of-library-microservices

2. Start Database Services

  docker-compose up -d

This will start three PostgreSQL instances:

• users-db: localhost:5431
• books-db: localhost:5432
• borrowing-db: localhost:5433

3. Build and Run Services

Build all services:

    # Build Users Service
    cd UsersService
    mvn clean install
    mvn spring-boot:run
    
    # Build Books Service  
    cd ../BooksService
    mvn clean install
    mvn spring-boot:run
    
    # Build Borrowing Service
    cd ../BorrowingService
    mvn clean install
    mvn spring-boot:run
    
    # Build and Run API Gateway
    cd ../ApiGateway
    mvn clean install
    mvn spring-boot:run

4. Verify Installation

Check if all services are running:

• API Gateway: http://localhost:8080
• Books Service: http://localhost:8081
• Borrowing Service: http://localhost:8082
• Users Service: http://localhost:8083