二. SpringCloud基本Rest微服务工程搭建

1. 父工程构建

1.1 Maven项目搭建

环境	版本
JDK	1.8
Maven	3.6+
Maven模板	maven-archetype-size
删除父工程src文件

1.2 父工程pom文件

回顾：

① Maven中dependencyManagement和dependencies的区别

​ Maven使用dependencyManagement元素来提供一种管理依赖版本号的方式。通常会在一个组织或者项 目的最顶层的父POM中看到。使用pom.xml中 的dependencyManagement元素能让所有中引用一个依赖而不用显示的列出版本号。Maven会沿着父子层次向上找，直到找到一个拥有dependencyManagement元素的项目，然后它就会使用这个元素中指定的版本号。另外如果某个子项目需要使用另外的版本只需要声明version即可。注意：dependencyManagement里只是声明依赖，并不实现引入，因此子项目要显示的声明需要的依赖。

② Maven中如何跳过单元测试

​ 在Idea的Maven侧栏点击闪电图标，使Maven跳过test生命周期即可。

<?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.polaris</groupId>
    <artifactId>com.polaris.springcloud</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>pom</packaging>

    <modules>

    </modules>

    <!-- 统一管理jar包版本 -->
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <junit.version>4.12</junit.version>
        <log4j.version>1.2.17</log4j.version>
        <lombok.version>1.16.18</lombok.version>
        <mysql.version>5.1.47</mysql.version>
        <druid.version>1.1.16</druid.version>
        <mybatis.spring.boot.version>1.3.0</mybatis.spring.boot.version>
    </properties>

    <!-- 子模块继承之后，提供作用：锁定版本+子modlue不用写groupId和version  -->
    <dependencyManagement>
        <dependencies>
            <!--spring boot 2.2.2-->
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>2.2.2.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--spring cloud Hoxton.SR1-->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Hoxton.SR1</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--spring cloud alibaba 2.1.0.RELEASE-->
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>2.1.0.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>${mysql.version}</version>
            </dependency>
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid</artifactId>
                <version>${druid.version}</version>
            </dependency>
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>${mybatis.spring.boot.version}</version>
            </dependency>
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>${junit.version}</version>
            </dependency>
            <dependency>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
                <version>${log4j.version}</version>
            </dependency>
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>${lombok.version}</version>
                <optional>true</optional>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <fork>true</fork>
                    <addResources>true</addResources>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

2. 微服务提供者支付Module模块

cloud-provider-payment8001

2.1 pom.xml

<?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>com.polaris.springcloud</artifactId>
        <groupId>com.polaris</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloud-provider-payment8001</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>
        <!--mysql-connector-java-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!--jdbc-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
         <!-- 通用配置 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
</project>

2.2 yml配置文件

server:
  port: 8001

spring:
  application:
    name: cloud-payment-service
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource            # 当前数据源操作类型
    driver-class-name: org.gjt.mm.mysql.Driver              # mysql驱动包
    url: jdbc:mysql://mpolaris.top:3306/cloud-test?useUnicode=true&characterEncoding=utf-8&useSSL=false
    username: root
    password: 123456

mybatis:
  mapperLocations: classpath:mapper/*.xml
  type-aliases-package: com.polaris.springcloud.entities    # 所有Entity别名类所在包

2.3 主启动类

/**
 * @Author polaris
 * @Date 2021/1/21 1:00
 */
@SpringBootApplication
public class PaymentMain {
    public static void main(String[] args) {
        SpringApplication.run(PaymentMain.class,args);
    }
}

2.4 业务类（简单演示）

建表

entities

主实体 与 Json封装体

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Payment implements Serializable {
    private Long id;
    private String serial;

}

@Data
@AllArgsConstructor
@NoArgsConstructor
public class CommonResult<T> {
    private Integer code;
    private String message;
    private T data;

    public CommonResult(Integer code, String message){
        this(code,message,null);
    }
}

dao

接口PaymentDao与mybatis映射文件PaymentMapper

@Mapper
public interface PaymentDao {

    int save(Payment payment);

    Payment getPaymentById(@Param("id") Long id);
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >

<mapper namespace="com.polaris.springcloud.dao.PaymentDao">

    <insert id="save" parameterType="Payment" useGeneratedKeys="true" keyProperty="id">
        insert into payment(serial)  values(#{serial});
    </insert>

    <resultMap id="BaseResultMap" type="com.polaris.springcloud.entities.Payment">
        <id column="id" property="id" jdbcType="BIGINT"/>
        <id column="serial" property="serial" jdbcType="VARCHAR"/>
    </resultMap>

    <select id="getPaymentById" parameterType="Long" resultMap="BaseResultMap">
        select * from payment where id=#{id};
    </select>

</mapper>

service

接口与实现类

@Service
public class PaymentServiceImpl implements PaymentService {
    @Resource
    private PaymentDao paymentDao;

    @Override
    public int save(Payment payment) {
        return paymentDao.save(payment);
    }

    @Override
    public Payment getPaymentById(Long id) {
        return paymentDao.getPaymentById(id);
    }
}

controller

@RestController
@Slf4j
@RequestMapping("/payment")
public class PaymentController {
    @Resource
    private PaymentService paymentService;

    @PostMapping("/save")
    public CommonResult save(Payment payment) {
        int result = paymentService.save(payment);
        log.info("===> result: " + result);
        if(result > 0) {
            return new CommonResult(200,"保存到数据库成功",result);
        }
        return new CommonResult(400,"保存到数据库失败",null);
    }

    @GetMapping("/get/{id}")
    public CommonResult<Payment> save(@PathVariable("id") Long id) {
        Payment paymentById = paymentService.getPaymentById(id);
        log.info("===> payment: " + paymentById);
        if(paymentById != null) {
            return new CommonResult(200,"查询成功",paymentById);
        }
        return new CommonResult(400,"查询失败",null);
    }
}

3. 开启Devtools热部署

3.1 聚合父类总工程pom.xml添加配置

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
            <configuration>
                <fork>true</fork>
                <addResources>true</addResources>
            </configuration>
        </plugin>
    </plugins>
</build>

3.2 当前工程添加devtools依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-devtools</artifactId>
    <scope>runtime</scope>
    <optional>true</optional>
</dependency>

3.3 Idea开启自动编译选项

3.4 开启热注册

快捷键 ctrl + shift + alt + /，打开Registry

勾选

重启Idea，即可测试代码时不用手动重启

注意：该功能只能在开发阶段使用，上线前一定要关闭

4. 微服务消费者订单Module模块

cloud-consumer-order80

4.1 pom.xml

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <scope>runtime</scope>
        <optional>true</optional>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

4.2 yml配置文件

server:
  port: 80

4.3 主启动类

4.4 RestTemplate引入

是什么

RestTemplate提供了多种便捷 访问远程Http服务 的方法，是一种简单便捷的访问restful服务模板类，是Spring提供的用于访问Rest服务的 客户端模板工具类

如何使用

官网使用：https://docs.spring.io/spring-framework/docs/5.2.2.RELEASE/javadoc-api/org/springframework/web/client/RestTemplate.html

使用restTemplate访问restful接口非常的简单粗暴。

• url REST请求地址
• requestMap 请求参数
• ResponseBean.classs HTTP响应转换被转换成的对象类型

config配置类

@Configuration
public class ApplicationContextConfig {
    @Bean
    public RestTemplate getRestTemplate() {
        return new RestTemplate();
    }
}

4.5 业务类

entities

与提供者支付模块一致

controller

@RestController
@Slf4j
@RequestMapping("/consumer")
public class OrderController {
    @Resource
    private RestTemplate restTemplate;

    private static final String PAYMENT_URL = "http://localhost:8001";

    @GetMapping("/payment/save")
    public CommonResult<Payment> save(Payment payment) {
        return restTemplate.postForObject(PAYMENT_URL + "/payment/save",
                payment,CommonResult.class);
    }

    @GetMapping("/payment/get/{id}")
    public CommonResult<Payment> get(@PathVariable("id") Long id) {
        return restTemplate.getForObject(PAYMENT_URL + "/payment/get/" + id,
                CommonResult.class);
    }
}

4.6 启动两个模块测试

启动两个模块没有出现Run Dashbord的问题

在工程目录下找.idea文件夹下的workspace.xml添加如下代码即可

<component name="RunDashboard">
    <option name="configurationTypes">
      <set>
        <option value="SpringBootApplicationConfigurationType" />
      </set>
    </option>
    <option name="ruleStates">
      <list>
        <RuleState>
          <option name="name" value="ConfigurationTypeDashboardGroupingRule" />
        </RuleState>
        <RuleState>
          <option name="name" value="StatusDashboardGroupingRule" />
        </RuleState>
      </list>
    </option>
</component>

插入成功但是没有内容的问题

解决：支付模块这里一定要加@RequestBody注解

@PostMapping("/save")
public CommonResult save(@RequestBody Payment payment) {
	int result = paymentService.save(payment);
	log.info("===> result: " + result);
	if(result > 0) {
	return new CommonResult(200,"保存到数据库成功",result);
	}
	return new CommonResult(400,"保存到数据库失败",null);
}

5. 工程重构 - 公共工程模块

5.1 发现问题 - 系统中有重复代码 entities

5.2 新建公共工程 cloud-api-common

重复代码，公共接口，第三方接口，工具类等都可以放在这里

pom.xml

Hutool是一个小而全的Java工具类库，是项目中“util”包友好的替代

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <scope>runtime</scope>
        <optional>true</optional>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
    <!-- hutool工具类 -->
    <dependency>
        <groupId>cn.hutool</groupId>
        <artifactId>hutool-all</artifactId>
        <version>5.1.0</version>
    </dependency>
</dependencies>

5.3 抽取多个模块的共同代码

将cloud-api-common安装到maven仓库

修改订单80和支付8001代码

• 删除各自原先的enntities

• 各自添加pom内容

<!-- 公共模块 -->
<dependency>
    <groupId>com.polaris</groupId>
    <artifactId>cloud-api-common</artifactId>
    <version>${project.version}</version>
</dependency>