我们本次是使用的电商项目中的商品、订单、用户为案例进行讲解。
maven: 3.3.9
数据库: MySQL 5.7
持久层: SpingData Jpa
其他: SpringCloud Alibaba 技术栈
springcloud-alibaba 父工程
shop-common 公共模块【实体类】
shop-user 用户微服务 【端口: 807x】
shop-product 商品微服务 【端口: 808x】
在微服务架构中,最常见的场景就是微服务之间的相互调用。我们以电商系统中常见的用户下单为例来演示微服务的调用:客户向订单微服务发起一个下单的请求,在进行保存订单之前需要调用商品微服务查询商品的信息。
我们一般把服务的主动调用方称为服务消费者,把服务的被调用方称为服务提供者。
在这种场景下,订单微服务就是一个服务消费者, 商品微服务就是一个服务提供者。
创建一个maven工程,然后在pom.xml文件中添加下面内容
4.0.0
org.springframework.boot
spring-boot-starter-parent
2.1.3.RELEASE
com.ruipeng
springcloud-alibaba
1.0-SNAPSHOT
pom
1.8
UTF-8
UTF-8
Greenwich.RELEASE
2.1.0.RELEASE
org.springframework.cloud
spring-cloud-dependencies
${spring-cloud.version}
pom
import
com.alibaba.cloud
spring-cloud-alibaba-dependencies
${spring-cloud-alibaba.version}
pom
import
版本对应:
(1)创建 shop-common 模块,在pom.xml中添加依赖
springcloud-alibaba
com.ruipeng
1.0-SNAPSHOT
4.0.0
shop-common
org.springframework.boot
spring-boot-starter-data-jpa
org.projectlombok
lombok
com.alibaba
fastjson
1.2.56
mysql
mysql-connector-java
5.1.6
(2) 创建实体类
//用户
@Entity(name = "shop_user")
@Data
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer uid;//主键
private String username;//用户名
private String password;//密码
private String telephone;//手机号
}
//商品
@Entity(name = "shop_product")
@Data
public class Product {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer pid;//主键
private String pname;//商品名称
private Double pprice;//商品价格
private Integer stock;//库存
}
//订单
@Entity(name = "shop_order")
@Data
public class Order {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long oid;//订单id
private Integer uid;//用户id
private String username;//用户名
private Integer pid;//商品id
private String pname;//商品名称
private Double pprice;//商品单价
private Integer number;//购买数量
}
步骤:
1 创建模块 导入依赖
2 创建SpringBoot主类
3 加入配置文件
4 创建必要的接口和实现类(controller service dao) 新建一个 shop-user 模块,然后进行下面操作
(1) 创建pom.xml
springcloud-alibaba
com.ruipeng
1.0-SNAPSHOT
4.0.0
shop-user
com.ruipeng
shop-common
1.0-SNAPSHOT
(2)编写主类
@SpringBootApplication
@EnableDiscoveryClient
public class UserApplication {
public static void main(String[] args) {
SpringApplication.run(UserApplication.class, args);
}
}
(3)创建配置文件
server:
port: 8071
spring:
application:
name: service-product
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql:///shop?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
username: root
password: root
jpa:
properties:
hibernate:
hbm2ddl:
auto: update
dialect: org.hibernate.dialect.MySQL5InnoDBDialect
1 创建一个名为 shop_product 的模块,并添加springboot依赖
springcloud-alibaba
com.ruipeng
1.0-SNAPSHOT
4.0.0
shop-product
org.springframework.boot
spring-boot-starter-web
com.ruipeng
shop-common
1.0-SNAPSHOT
2 创建工程的主类
package com.ruipeng;
@SpringBootApplication
public class ProductApplication {
public static void main(String[] args) {
SpringApplication.run(ProductApplication.class, args);
}
}
3 创建配置文件application.yml
server:
port: 8081
spring:
application:
name: service-product
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql:///shop?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
username: root
password: root
jpa:
properties:
hibernate:
hbm2ddl:
auto: update
dialect: org.hibernate.dialect.MySQL5InnoDBDialect
4 创建ProductDao接口
package com.itheima.dao;
public interface ProductDao extends JpaRepository {
}
5 创建ProductService接口和实现类
package com.ruipeng.service.impl;
@Service
public class ProductServiceImpl implements ProductService {
@Autowired
private ProductDao productDao;
@Override
public Product findByPid(Integer pid) {
return productDao.findById(pid).get();
} }
6 创建Controller
@RestController
@Slf4j
public class ProductController {
@Autowired
private ProductService productService;
@GetMapping("/product/{pid}")
public Product product(@PathVariable("pid") Integer pid) {
Product product = productService.findByPid(pid);
log.info("查询到商品:" + JSON.toJSONString(product));
return product;
} }
7 启动工程,等到数据库表创建完毕之后,加入测试数据
INSERT INTO shop_product VALUE(NULL,'小米','1000','5000');
INSERT INTO shop_product VALUE(NULL,'华为','2000','5000');
INSERT INTO shop_product VALUE(NULL,'苹果','3000','5000');
INSERT INTO shop_product VALUE(NULL,'OPPO','4000','5000');
8 通过浏览器访问服务
1 创建一个名为 shop-order 的模块,并添加springboot依赖
springcloud-alibaba
com.ruipeng
1.0-SNAPSHOT
4.0.0
shop-order
org.springframework.boot
spring-boot-starter-web
com.ruipeng
shop-common
1.0-SNAPSHOT
2 创建工程的主类
package com.ruipeng;
@SpringBootApplication
public class OrderApplication {
public static void main(String[] args) {
SpringApplication.run(OrderApplication.class, args);
}
}
3 创建配置文件application.yml
server:
port: 8091
spring:
application:
name: service-product
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql:///shop?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
username: root
password: root
jpa:
properties:
hibernate:
hbm2ddl:
auto: update
dialect: org.hibernate.dialect.MySQL5InnoDBDialect
4 创建OrderDao接口
package com.ruipeng.dao;
public interface OrderDao extends JpaRepository {
}
5 创建OrderService接口和实现类
@Service
public class OrderServiceImpl implements OrderService {
@Autowired
private OrderDao orderDao;
@Override
public void save(Order order) {
orderDao.save(order);
} }
6 创建RestTemplate
@SpringBootApplication
public class OrderApplication {
public static void main(String[] args) {
SpringApplication.run(OrderApplication.class, args);
}
@Bean
public RestTemplate getRestTemplate() {
return new RestTemplate();
} }
7 创建Controller
package com.ruipeng.controller;
@RestController
@Slf4j
public class OrderController {
@Autowired
private RestTemplate restTemplate;
@Autowired
private OrderService orderService;
//准备买1件商品
@GetMapping("/order/prod/{pid}")
public Order order(@PathVariable("pid") Integer pid) {
log.info(">>客户下单,这时候要调用商品微服务查询商品信息");
//通过restTemplate调用商品微服务
Product product = restTemplate.getForObject(
"http://localhost:8081/product/" + pid, Product.class);
log.info(">>商品信息,查询结果:" + JSON.toJSONString(product));
Order order = new Order();
order.setUid(1);
order.setUsername("测试用户");
order.setPid(product.getPid());
order.setPname(product.getPname());
order.setPprice(product.getPprice());
order.setNumber(1);
orderService.save(order);
return order;
}
}