[SpringBoot] MSA+JPA로 간단한 소스 구현하기

Eureka 서버와 JPA로 아주 간단한 쇼핑몰 BackEnd 소스를 작성하였습니다. SpringBoot로 구현하였으며, MariaDB를 사용하였습니다.

1. 테이블 생성

CREATE TABLE `products` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) DEFAULT NULL,
  `description` varchar(255) DEFAULT NULL,
  `price` double NOT NULL,
  `stock` double NOT NULL,
  `created_at` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`id`)
);

CREATE TABLE `users` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `username` varchar(255) DEFAULT NULL,
  `password` varchar(255) DEFAULT NULL,
  `email` varchar(255) DEFAULT NULL,
  `created_at` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`id`)
);

CREATE TABLE `orders` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `user_id` bigint(20) NOT NULL,
  `product_id` bigint(20) NOT NULL,
  `total` double NOT NULL,
  `created_at` timestamp NULL DEFAULT current_timestamp(),
  PRIMARY KEY (`id`)
);

• products : 상품정보를 담을 테이블
• users : 사용자 정보를 담을 테이블
• orders : 주문 정보를 담을 테이블

2. 데이터 입력

• users와 products 테이블에 테스트 데이터를 입력합니다.

INSERT INTO mymall.users (username,password,email)
VALUES ('차영빈','1234','zero-bin@navercom');

INSERT INTO mymall.products (name,description,price,stock)
VALUES ('모니터','24인치 모니터입니다',50000,1);

3. 소스작성

• SpringBoot 프로젝트를 총 4개 생성합니다. 자세한 소스는 Github를 참고해 주세요. 실행순서는 "유레카서버 > 사용자 서비스" > "상품 서비스" > "주문 서비스" 순으로 실행시키시면 됩니다.
  • EurekaServer : 유레카 서버
  • UserService : 사용자 서비스
  • ProductService : 상품 서비스
  • OrderService : 주문 서비스

 

3.1. Eureka Server

#build.gradle
dependencies {
    implementation 'org.springframework.cloud:spring-cloud-starter-netflix-eureka-server'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
    testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
}

dependencyManagement {
    imports {
        mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
    }
}


#application.yml
server:
  port: 1220

spring:
  application:
    name: MyMallService

eureka:
  client:
    register-with-eureka: false
    fetch-registry: false
    
    
#SpringBootApplication
@EnableEurekaServer
@SpringBootApplication
public class MyMallApplication {
  public static void main(String[] args) {
    SpringApplication.run(MyMallApplication.class, args);
  }
}

설정이 완료되면 유레카 서버를 확인할 수 있습니다.

3.2. UserService

#build.gradle
dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
    implementation 'org.springframework.cloud:spring-cloud-starter-netflix-eureka-client'
    implementation 'org.springframework.cloud:spring-cloud-starter-openfeign'
    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
    implementation 'org.mariadb.jdbc:mariadb-java-client:3.0.4'

    compileOnly 'org.projectlombok:lombok'
    developmentOnly 'org.springframework.boot:spring-boot-devtools'
    annotationProcessor 'org.projectlombok:lombok'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
    testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
}

dependencyManagement {
    imports {
        mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
    }
}


#application.yml
server:
  port: 1221

spring:
  application:
    name: user-service

  datasource:
    url: jdbc:mariadb://localhost:3306/mymall
    username: root
    password: root

  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true

eureka:
  instance:
    instance-id: ${spring.cloud.client.hostname}:${spring.application.instance_id:${random.value}}
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://127.0.0.1:1220/eureka
      
      
#SpringBootApplication
@EnableDiscoveryClient
@SpringBootApplication
public class UserServiceApplication {
  public static void main(String[] args) {
    SpringApplication.run(UserServiceApplication.class, args);
  }
}

#User.java
@Getter
@Setter
@Entity(name = "users")
public class User {
  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  private Long id;
  private String username;
  private String password;
  private String email;
  private String created_at;
}


#UserRepository.java
public interface UserRepository extends JpaRepository<User, Long> {
}


#UserController.java
@RestController
@RequiredArgsConstructor
@RequestMapping("/users")
public class UserController {

  private final UserRepository _userRepository;

  @GetMapping("/{id}")
  public ResponseEntity<User> getUserById(@PathVariable Long id) {
    Optional<User> user = _userRepository.findById(id);
    return user.map(ResponseEntity::ok).orElseGet(() -> ResponseEntity.notFound().build());
  }
}

3.3. ProductService

#build.gradle
dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
    implementation 'org.springframework.cloud:spring-cloud-starter-netflix-eureka-client'
    implementation 'org.springframework.cloud:spring-cloud-starter-openfeign'
    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
    implementation 'org.mariadb.jdbc:mariadb-java-client:3.0.4'

    compileOnly 'org.projectlombok:lombok'
    developmentOnly 'org.springframework.boot:spring-boot-devtools'
    annotationProcessor 'org.projectlombok:lombok'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
    testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
}

dependencyManagement {
    imports {
        mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
    }
}


#application.yml
server:
  port: 1221

spring:
  application:
    name: product-service

  datasource:
    url: jdbc:mariadb://localhost:3306/mymall
    username: root
    password: root

  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true

eureka:
  instance:
    instance-id: ${spring.cloud.client.hostname}:${spring.application.instance_id:${random.value}}
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://127.0.0.1:1220/eureka
      
      
#SpringBootApplication
@EnableDiscoveryClient
@SpringBootApplication
public class ProductServiceApplication {
  public static void main(String[] args) {
    SpringApplication.run(ProductServiceApplication.class, args);
  }
}

#Product.java
@Getter
@Setter
@Entity(name = "products")
public class Product {
  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  private Long id;
  private String name;
  private String description;
  private double price;
  private double stock;
  private String created_at;
}


#ProductRepository.java
public interface ProductRepository extends JpaRepository<Product, Long> {
}


#ProductController.java
@RestController
@RequiredArgsConstructor
@RequestMapping("/products")
public class ProductController {

  private final ProductRepository _productRepository;

  @GetMapping("/{id}")
  public ResponseEntity<Product> getProductById(@PathVariable Long id) {
    Optional<Product> product = _productRepository.findById(id);
    return product.map(ResponseEntity::ok).orElseGet(() -> ResponseEntity.notFound().build());
  }
}

3.4. OrderService

#build.gradle
dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
    implementation 'org.springframework.cloud:spring-cloud-starter-netflix-eureka-client'
    implementation 'org.springframework.cloud:spring-cloud-starter-openfeign'
    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
    implementation 'org.mariadb.jdbc:mariadb-java-client:3.0.4'

    compileOnly 'org.projectlombok:lombok'
    developmentOnly 'org.springframework.boot:spring-boot-devtools'
    annotationProcessor 'org.projectlombok:lombok'
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
    testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
}

dependencyManagement {
    imports {
        mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
    }
}


#application.yml
server:
  port: 1223

spring:
  application:
    name: order-service

  datasource:
    url: jdbc:mariadb://localhost:3306/mymall
    username: root
    password: root

  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true

eureka:
  instance:
    instance-id: ${spring.cloud.client.hostname}:${spring.application.instance_id:${random.value}}
  client:
    register-with-eureka: true
    fetch-registry: true
    service-url:
      defaultZone: http://127.0.0.1:1220/eureka
      
      
#SpringBootApplication
@EnableDiscoveryClient
@SpringBootApplication
@EnableFeignClients
public class OrderServiceApplication {
  public static void main(String[] args) {
    SpringApplication.run(OrderServiceApplication.class, args);
  }
}

#UserClient.java
@FeignClient(name = "user-service")
public interface UserClient {
  @GetMapping("/users/{id}")
  User getUserById(@PathVariable Long id);
}


#ProductClient.java
@FeignClient(name = "product-service")
public interface ProductClient {
  @GetMapping("/products/{id}")
  Product getProductById(@PathVariable Long id);
}


#User.java
@Getter
@Setter
public class User {
  private Long id;
  private String username;
  private String password;
  private String email;
  private String created_at;
}


#Product.java
@Getter
@Setter
public class Product {
  private Long id;
  private String name;
  private String description;
  private double price;
  private double stock;
  private String created_at;
}


#Order.java
@Getter
@Setter
@Entity(name = "orders")
public class Order {
  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  private Long id;
  private Long user_id;
  private Long product_id;
  private double total;
  private String created_at;
}


#OrderRepository.java
public interface OrderRepository extends JpaRepository<Order, Long> {
}


#OrderController.java
@RestController
@RequiredArgsConstructor
@RequestMapping("/orders")
public class OrderController {

  private final OrderRepository _orderRepository;
  private final UserClient _userClient;
  private final ProductClient _productClient;

  @PostMapping
  public ResponseEntity<Order> createOrder(@RequestBody Order order) {
    User user = _userClient.getUserById(order.getUser_id());
    if (user == null) {
      return ResponseEntity.badRequest().build();
    }

    Product product = _productClient.getProductById(order.getProduct_id());
    if (product == null) {
      return ResponseEntity.badRequest().build();
    }

    Order savedOrder = _orderRepository.save(order);
    return ResponseEntity.ok(savedOrder);
  }

}

4. 호출

• UserService 직접 호출(GET) : http://192.168.202.13:1221/users/1
• ProductSerivce 직접 호출(GET) : http://192.168.202.13:1222/products/1
• OrderService 호출(POST) : http://192.168.202.13:1223/orders

{

    "user_id" : 1,

    "product_id" : 1,

    "total": 50000

}

감사합니다.