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+# Library API Microservices
+
+[![Java Build Status](https://github.com/earlspilner/library-api/actions/workflows/maven-build.yml/badge.svg)](https://github.com/earlspilner/the-github-times/actions/workflows/maven-build.yml) [![License](https://img.shields.io/badge/License-MIT-blue.svg)](https://opensource.org/licenses/MIT)
+
+This project implements a microservices architecture for managing a library system. The system consists of several services, each responsible for its specific functionality.
+
+## Services
+
+### 1. **Authentication Server**
+The authentication service is responsible for issuing JWT tokens for users in the system.
+
+- **Main features:**
+  - User authentication.
+  - Issuing access and refresh tokens.
+  - Token renewal.
+
+- **Endpoints:**
+
+  `POST /api/auth/login`
+
+  `POST /api/auth/refresh?refreshToken=`  
+
+### 2. **Books Service**
+The book management service handles operations related to books, including creation, updating, deletion, and retrieving information about books.
+
+- **Main features:**
+  - Managing book data.
+  - Searching for books.
+
+- **Endpoints:**  
+  `POST /api/books`
+
+  `GET /api/books/{bookId}`
+
+  `GET /api/books/isbn/{isbn}`
+
+  `PUT /api/books/{bookId}`
+
+  `DELETE /api/books/{bookId}`
+
+### 3. **Discovery Server**
+The discovery server (Eureka) allows other services to register and discover each other dynamically within the microservices environment.
+
+- **Main features:**
+  - Service registration and discovery.
+
+### 4. **API Gateway**
+The API Gateway acts as the entry point to the system, routing requests to the appropriate services.
+
+- **Main features:**
+  - Request routing.
+  - Centralized authentication and authorization.
+
+- **Endpoints:**  
+  `any request on port :8080` 
+
+### 5. **Library Service**
+The library management service stores information about available books in the library, including which book is free and which is on loan.
+
+- **Main features:**
+  - Store information about books in library
+
+- **Endpoints:**  
+  `POST /api/library`
+
+  `GET /api/library/{bookId}`
+
+  `PUT /api/library/{bookId}`
+
+  `DELETE /api/library/{bookId}`
+
+### 6. **Loan Service**
+The loan service manages book loan information, including tracking due dates and book returns.
+
+- **Main features:**
+  - Tracking loaned books.
+  - Managing return deadlines.
+
+- **Endpoints:**  
+  `POST /api/loans`
+
+  `GET /api/loans/{loanId}`
+
+  `PUT /api/loans/{bookId}`
+
+### 7. **User Service**
+The user management service is responsible for storing and managing user accounts.
+
+- **Main features:**
+  - Managing user registration and details.
+
+- **Endpoints:**  
+  `POST /api/users`
+
+  `GET /api/users/{username}`
+
+  `PUT /api/users/{username}`
+
+  `DELETE /api/users/{id}`
+
+## Architecture
+
+The project uses a microservices architecture where each service is independent and communicates with others via REST APIs (OpenFeign client). **Eureka Discovery Server** is used for service registration and discovery, and **Spring Cloud Gateway** routes requests between services.
+
+### Main components:
+- **Spring Boot** - for building each microservice.
+- **Eureka** - for service registration and discovery.
+- **Spring Cloud Gateway** - for request routing through the API gateway.
+- **Feign** - for simplifying REST API calls to other microservices.
+- **Spring Security** - for authentication and authorization.
+
+## Requirements
+
+- **Java 21** or higher.
+- **Maven 3.8.7+** for building the project.
+
+## Running the Project
+
+1. Clone the repository:
+   ```bash
+   git clone https://github.com/earlspilner/library-api.git
+   ```
+
+2. Navigate to the project's root directory:
+   ```bash
+   cd library-api
+   ```
+
+3. Build all services:
+   ```bash
+   mvn clean install
+   ```
+
+4. Start each service, beginning with *Discovery Server*:
+   ```bash
+   cd library-api-discovery-server
+   mvn spring-boot:run
+   ```
+Repeat the process for each service in the required order.
+
+### Environment Variables
+
+| Variable Name              | Description                              | Default Value |
+|----------------------------|------------------------------------------|---------------|
+| `jwt.secret.key`            | JWT secret key, generated via KeyGen.java| (Generate it) |
+| `jwt.expiration.access`     | Access token expiration time (in ms)     | 300000 (5 minutes) |
+| `jwt.expiration.refresh`    | Refresh token expiration time (in ms)    | 3600000 (1 hour) |
+
+## Authentication and Authorization
+
+The system uses JWT tokens for authentication and authorization. After successful login via library-api-authentication-server, the client receives access and refresh tokens, which should be included in the Authorization header when making requests to other services.
+
+## API Documentation
+
+Each service has its own Swagger documentation available at:
+```arduino
+http://localhost:{$SERVICE_PORT}/swagger-ui.html
+```