商品微服务:查询商品列表
订单微服务:创建订单
1.技术选型
持久层: SpingData Jpa
数据库: MySQL5.7
其他: SpringCloud Alibaba 技术栈
2.模块设计
— shop-parent 父工程
--- shop-product-api 商品微服务api 【存放商品实体】
--- shop-product-server 商品微服务 【端口:8081】
--- shop-order-api 订单微服务api 【存放订单实体】
--- shop-order-server 订单微服务 【端口:8091】
3.微服务调用
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。
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。
4.版本说明
版本说明
组件版本关系
5.创建父工程
创建一个maven工程,然后在pom.xml文件中添加下面内容
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.sun</groupId>
<artifactId>shop-parent</artifactId>
<packaging>pom</packaging>
<version>1.0-SNAPSHOT</version>
<modules>
<module>shop-product-api</module>
<module>shop-product-server</module>
<module>shop-order-api</module>
<module>shop-order-server</module>
</modules>
<!--父工程-->
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.6.11</version>
</parent>
<!--依赖版本的锁定-->
<properties>
<java.version>11</java.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<spring-cloud.version>2021.0.4</spring-cloud.version>
<spring-cloud-alibaba.version>2021.0.4.0</spring-cloud-alibaba.version>
</properties>
<dependencyManagement>
<dependencies>
<!-- SpringCloud 微服务 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<!-- SpringCloud Alibaba 微服务 -->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-alibaba-dependencies</artifactId>
<version>${spring-cloud-alibaba.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
</project>
6.创建商品微服务
1.创建shop-product-api项目,然后在pom.xml文件中添加下面内容
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>shop-parent</artifactId>
<groupId>com.sun</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>shop-product-api</artifactId>
<!--依赖-->
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
</dependencies>
</project>
2 创建实体类
package com.sun.pojo;
//商品
import lombok.Data;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
//商品
@Entity(name = "t_shop_product")
@Data
public class Product {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long pid;//主键
private String pname;//商品名称
private Double pprice;//商品价格
private Integer stock;//库存
}
3.创建shop-product-server项目,然后在pom.xml文件中添加下面内容
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>shop-parent</artifactId>
<groupId>com.sun</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>shop-product-server</artifactId>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.83</version>
</dependency>
<dependency>
<groupId>com.sun</groupId>
<artifactId>shop-product-api</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
</dependencies>
</project>
4.编写启动类ProductServer.java
@SpringBootApplication
public class ProductServer {
public static void main(String[] args) {
SpringApplication.run(ProductServer.class, args);
}
}
5.编写配置文件application.yml
server:
port: 8081
spring:
application:
name: product-service
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql:///shop-product?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=false
username: root
password: admin
jpa:
properties:
hibernate:
hbm2ddl:
auto: update
dialect: org.hibernate.dialect.MySQL5InnoDBDialect
6.在数据库中创建shop-product的数据库
7.创建ProductDao
public interface ProductDao extends JpaRepository<Product,Long> {
}
8.创建ProductService接口和实现类
@Service
public class ProductServiceImpl implements ProductService {
@Autowired
private ProductDao productDao;
@Override
public Product findByPid(Long pid) {
return productDao.findById(pid).get();
}
}
9.创建Controller
@RestController
@Slf4j
@RequestMapping("/product")
public class ProductController {
@Autowired
private ProductService productService;
//商品信息查询
@RequestMapping("/get")
public Product findByPid(Long pid) {
log.info("接下来要进行{}号商品信息的查询", pid);
Product product = productService.findByPid(pid);
log.info("商品信息查询成功,内容为{}", JSON.toJSONString(product));
return product;
}
}
10.启动工程,等到数据库表创建完毕之后,加入测试数据
INSERT INTO t_shop_product VALUE(NULL,'小米','1000','5000');
INSERT INTO t_shop_product VALUE(NULL,'华为','2000','5000');
INSERT INTO t_shop_product VALUE(NULL,'苹果','3000','5000');
INSERT INTO t_shop_product VALUE(NULL,'OPPO','4000','5000');
浏览器访问服务: http://localhost:8081/product/get?pid=1
7 创建订单微服务
1.创建shop-order-api项目,然后在pom.xml文件中添加下面内容
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>shop-parent</artifactId>
<groupId>com.sun</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>shop-order-api</artifactId>
<!--依赖-->
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
</dependencies>
</project>
2 创建实体类
package com.sun.pojo;
import lombok.Data;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
//订单
@Entity(name = "t_shop_order")
@Data
public class Order {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long oid;//订单id
//用户
private Long uid;//用户id
private String username;//用户名
//商品
private Long pid;//商品id
private String pname;//商品名称
private Double pprice;//商品单价
//数量
private Integer number;//购买数量
}
3.创建shop-order-server项目,然后在pom.xml文件中添加下面内容
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>shop-parent</artifactId>
<groupId>com.sun</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>shop-order-server</artifactId>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.83</version>
</dependency>
<dependency>
<groupId>com.sun</groupId>
<artifactId>shop-order-api</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
</dependencies>
</project>
4.编写启动类OrderServer.java
@SpringBootApplication
public class OrderServer {
public static void main(String[] args) {
SpringApplication.run(OrderServer.class, args);
}
}
5.编写配置文件application.yml
server:
port: 8091
spring:
application:
name: order-service
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql:///shop-order?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=false
username: root
password: 123456
jpa:
properties:
hibernate:
hbm2ddl:
auto: update
dialect: org.hibernate.dialect.MySQL5InnoDBDialect
6.在数据库中创建shop-order的数据库
7.创建OrderDao
public interface OrderDao extends JpaRepository<Order,Long> {
}
8.创建OrderService接口和实现类
public interface OrderService {
Order createOrder(Long productId, Long userId);
}
package com.sun.service.impl;
import com.alibaba.fastjson.JSON;
import com.sun.dao.OrderDao;
import com.sun.pojo.Order;
import com.sun.pojo.Product;
import com.sun.service.OrderService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
/**
* @author lk
* @version 1.0.0
* @Description TODO
* @createTime 2025/5/8 4:25
*/
@Service
@Slf4j
public class OrderServiceImpl implements OrderService{
@Autowired
private OrderDao orderDao;
@Override
public Order createOrder(Long productId, Long userId) {
log.info("接收到{}号商品的下单请求,接下来调用商品微服务查询此商品信息", productId);
//远程调用商品微服务,查询商品信息
Product product = null;
log.info("查询到{}号商品的信息,内容是:{}", productId, JSON.toJSONString(product));
//创建订单并保存
Order order = new Order();
order.setUid(userId);
order.setUsername("叩丁狼教育");
order.setPid(productId);
order.setPname(product.getPname());
order.setPprice(product.getPprice());
order.setNumber(1);
orderDao.save(order);
log.info("创建订单成功,订单信息为{}", JSON.toJSONString(order));
return order;
}
}
8.服务间如何进行远程调用
商品微服务已经提供了数据接口了,订单微服务应该如何去调用呢?
其实就是如何通过Java代码去调用一个http的接口地址,我们可以使用RestTemplate来进行调用.
1.在启动类上添加RestTemplate的Bean配置
@SpringBootApplication
public class OrderServer {
public static void main(String[] args) {
SpringApplication.run(OrderServer.class,args);
}
@Bean
public RestTemplate restTemplate(){
return new RestTemplate();
}
}
2.在OrderServiceImpl中注入RestTemplate并实现远程调用
@Service
@Slf4j
public class OrderServiceImpl implements OrderService{
@Autowired
private OrderDao orderDao;
@Autowired
private RestTemplate restTemplate;
@Override
public Order createOrder(Long productId, Long userId) {
log.info("接收到{}号商品的下单请求,接下来调用商品微服务查询此商品信息", productId);
//远程调用商品微服务,查询商品信息
Product product = restTemplate.getForObject(
"http://localhost:8081/product/get?pid="+productId,Product.class);;
log.info("查询到{}号商品的信息,内容是:{}", productId, JSON.toJSONString(product));
//创建订单并保存
Order order = new Order();
order.setUid(userId);
order.setUsername("叩丁狼教育");
order.setPid(productId);
order.setPname(product.getPname());
order.setPprice(product.getPprice());
order.setNumber(1);
orderDao.save(order);
log.info("创建订单成功,订单信息为{}", JSON.toJSONString(order));
return order;
}
}
虽然我们已经可以实现微服务之间的调用。但是我们把服务提供者的网络地址(ip,端口)等硬编码到了代码中.
这种做法存在许多问题:
- 一旦服务提供者地址变化,就需要手工修改代码
- 一旦是多个服务提供者,无法实现负载均衡功能
- 一旦服务变得越来越多,人工维护调用关系困难
那么应该怎么解决呢, 这时候就需要通过注册中心动态的实现服务治理