微服务架构编码构建

**约定>配置>编码**

1、构建父工程

1-1、创建项目

1-2、字符编码

1-3、注解生效激活

1-4、java编译版本选择：java8

1-5、父工程pom文件

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<?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.jcvv.springcloud</groupId>
    <artifactId>springCloud2023</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>pom</packaging>


    <!-- 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>

    <!-- 子块基础之后，提供作用：锁定版本 + 子module不用写 groupId 和 version -->
    <dependencyManagement>
        <dependencies>
            <!-- 下面三个基本是微服务架构的标配 -->
            <!--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 阿里巴巴-->
            <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>

            <!--mysql-->
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>${mysql.version}</version>
                <scope>runtime</scope>
            </dependency>
            <!-- druid-->
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid</artifactId>
                <version>${druid.version}</version>
            </dependency>
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>${mybatis.spring.boot.version}</version>
            </dependency>
            <!--junit-->
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>${junit.version}</version>
            </dependency>
            <!--log4j-->
            <dependency>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
                <version>${log4j.version}</version>
            </dependency>

        </dependencies>

    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>2.3.7.RELEASE</version>
                <configuration>
                    <fork>true</fork>
                    <addResources>true</addResources>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>
1-5-1、技术问题

问题一、

当导入完父类的pom文件时，会导入依赖失败

原因：maven仓库中不存在该依赖，dependencyManagement附庸于已存在的依赖

解决方案：把 标签去掉之后，填写依赖版本，下载完成后，在重新添加标签

问题二、

true爆红

解决方案：给pluin添加版本号 2.3.7.RELEASE

2、Rest微服务工程构建

2-1、创建支付模块moudle 8001

父pom变化

第一步:编写pom

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<?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>springCloud2023</artifactId>
        <groupId>com.jcvv.springcloud</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>
        <!-- 图形化显示-->
        <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>
        <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>

第二步：编写application.yml

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server:
  port: 8001

spring:
  application:
    name: cloud-payment-service # 项目名,也是注册的名字

  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://localhost:3306/db2019?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=UTC
    username: root
    password: root

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

第三步:编写主启动类

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package com.jcvv.springcloud;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * @Classname PaymentMain8001
 * @Description chengzhi
 * @Created by chengzhi
 */
@SpringBootApplication
public class PaymentMain8001 {
    public static void main(String[] args) {
        SpringApplication.run(PaymentMain8001.class, args);
    }
}

第四步：业务实现

1、建立SQL表(payment)

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DROP DATABASE IF EXISTS springcloud2023
CREATE DATABASE springcloud2023;
USE springcloud2023;
CREATE TABLE `payment`(
    `id` BIGINT(20) NOT NULL AUTO_INCREMENT COMMENT 'ID',
    `serial` VARCHAR(200) DEFAULT '',
    PRIMARY KEY (`id`)
)ENGINE=INNODB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
SELECT * FROM payment;

2、创建实体entities

抽取entities实体类到该模块中

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package com.jcvv.springcloud.entities;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

/**
 * @Classname CommonResult
 * @Description chengzhi
 * @Created by chengzhi
 */
@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);
    }
}

3、编写dao层

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package com.jcvv.springcloud.dao;
import com.jcvv.springcloud.entities.Payment;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;

/**
 * @Classname PaymentDao
 * @Description chengzhi
 * @Created by chengzhi
 */
@Mapper
public interface PaymentDao {
    public int create(Payment payment);
    public Payment getPaymentById(@Param("id")long id);
}

编写mybatis映射文件PaymentMapper.xml

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<?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.jcvv.springcloud.dao.PaymentDao">

    <insert id="create" parameterType="Payment" useGeneratedKeys="true" keyProperty="id">
        insert into payment(serial)
        values (#{serial});
    </insert>
    <resultMap id="BaseResultMap" type="com.jcvv.springcloud.entities.Payment">
        <id column="id" property="id" jdbcType="BIGINT"></id>
        <result column="serial" property="serial" jdbcType="VARCHAR"></result>
    </resultMap>
    <select id="getPaymentById" parameterType="Long" resultMap="BaseResultMap">
        select *
        from payment
        where id = #{id};
    </select>
</mapper>

4、编写service层

4.1、编写PaymentService

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package com.jcvv.springcloud.service;

import com.jcvv.springcloud.entities.Payment;
import org.apache.ibatis.annotations.Param;

/**
 * @Classname PaymentService
 * @Description chengzhi
 * @Created by chengzhi
 */
public interface PaymentService {
    public int create(Payment payment);
    public Payment getPaymentById(@Param("id")long id);
}

4.2、编写PaymentServiceImpl

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package com.jcvv.springcloud.service.impl;

import com.jcvv.springcloud.dao.PaymentDao;
import com.jcvv.springcloud.entities.Payment;
import com.jcvv.springcloud.service.PaymentService;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

/**
 * @Classname PaymentServiceImpl
 * @Description chengzhi
 * @Created by chengzhi
 */
@Service
public class PaymentServiceImpl implements PaymentService {
    @Resource
    private PaymentDao paymentDao;
    @Override
    public int create(Payment payment) {
        return paymentDao.create(payment);
    }

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

5、编写controller层

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package com.jcvv.springcloud.controller;

import com.jcvv.springcloud.entities.CommonResult;
import com.jcvv.springcloud.entities.Payment;
import com.jcvv.springcloud.service.PaymentService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

/**
 * @Classname PaymentController
 * @Description chengzhi
 * @Created by chengzhi
 */
@RestController
@Slf4j
public class PaymentController {
    @Resource
    private PaymentService paymentService;

    @PostMapping(value = "/payment/create")
    public CommonResult create(@RequestBody Payment payment) {
        int result = paymentService.create(payment);
        log.info("*******插入结果" + result);
        if (result > 0) {
            return new CommonResult(200, "插入数据成功!", result);

        } else {
            return new CommonResult(444, "插入数据失败", null);
        }
    }

    @GetMapping(value = "/payment/get/{id}")
    public CommonResult getPaymentById(@PathVariable("id") Long id) {
        Payment payment = paymentService.getPaymentById(id);
        log.info("*******插入结果" + payment);
        if (payment !=null) {
            return new CommonResult(200, "查询成功!", payment);

        } else {
            return new CommonResult(444, "查询失败，没有对应记录", null);
        }
    }
}

6、接口测试

2-2、热加载

1、方式一、DevTools

1、导入依赖

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

2、方式二、热加载之JRebel

安装JRebel

1、在IDEA中一次点击 File->Settings->Plugins->Brows Repositories
2、在搜索框中输入JRebel进行搜索
3、找到JRebel for intellij
4、install
5、安装好之后需要restart IDEA

激活

JRebel并非免费的插件，需要激活之后才能使用。
1、首先到github上去下载一个反向代理软件，我下载的是windows x64版本。

下载地址

2、双击运行我们下载的程序

3、激活JRebel配置信息

第一行输入 http://127.0.0.1:8888/d3545f42-7b88-4a77-a2da-5242c46d4bc2
第二行输入正确的邮箱格式，例如： test@123.com
勾选同意协议，再点击Activate JRebel 按钮验证激活
提示：d3545f42-7b88-4a77-a2da-5242c46d4bc2为UUID,可以自己生成，并且必须是UUID才能通过验证

4、之后还会弹出来页面，相信你能应付。最后别忘了把JRebel设置为offline模式 点一下work offline

3、进行系统设置

1、settings配置打勾

2、打开父类pom文件

按ctrl+alt+shift+/ 弹出窗口，然后进入Registry ，勾选自动编译 -> compiler.automake.allow.when.app.running

3、重启IDEA

2-3、创建消费者订单模块moudle

第一步：创建模块

创建模块cloud-consumer-order80

第二步 ：导入依赖

导入依赖（此处俺被坑了，没有用到的mybatis和数据库依赖不到导入，不然运行会出错）

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<?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>springCloud2023</artifactId>
        <groupId>com.jcvv.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloud-consumer-order80</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- 图形化显示-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!--  devtools-->
        <!--        <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>

第三步：编写application.yml

编写application.yml文件

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server:
  port: 80

第四步：编写主启动类

编写主启动类

com.jcvv.springcloud.OrderMain80

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package com.jcvv.springcloud;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * @Classname OrderMain80
 * @Description chengzhi
 * @Created by chengzhi
 */
@SpringBootApplication
public class OrderMain80 {
    public static void main(String[] args) {
        SpringApplication.run(OrderMain80.class);
    }
}

第五步业务实现

业务实现

1、编写实体类

Payment

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package com.jcvv.springcloud.entities;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.io.Serializable;

/**
 * @Classname Payment
 * @Description chengzhi
 * @Created by chengzhi
 */
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Payment implements Serializable {
    private  Long id;
    private String serial;
}

CommonResult

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package com.jcvv.springcloud.entities;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

/**
 * @Classname CommonResult
 * @Description chengzhi
 * @Created by chengzhi
 */
@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);
    }
}

2、controller层
3、RestTemplate介绍

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集。

官方网址：https://docs.spring.io/spring-framework/docs/5.2.2.RELEASE/javadoc-api/org/springframework/web/client/RestTemplate.html

使用

使用restTemplate访问restful接口非常的简单粗暴无脑。(url, requestMap, ResponseBean.class)这三个参数分别代表 REST请求地址、请求参数、HTTP响应转换被转换成的对象类型。

config配置类

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package com.jcvv.springcloud.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;

/**
 * @Classname ApplicationContextConfig
 * @Description chengzhi
 * @Created by chengzhi
 */
@Configuration
public class ApplicationContextConfig {
    @Bean
    public RestTemplate getRestTemplate() {
        return new RestTemplate();
    }
}

4、controller类
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package com.jcvv.springcloud.controller;

import com.jcvv.springcloud.entities.CommonResult;
import com.jcvv.springcloud.entities.Payment;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import javax.annotation.Resource;

/**
 * @Classname OrderController
 * @Description chengzhi
 * @Created by chengzhi
 */
@RestController
@Slf4j
public class OrderController {
    public static final String PAYMENT_URL = "http://localhost:8001";
    @Resource
    private RestTemplate restTemplate;

    /**
     * @param payment
     * @return
     */
    @GetMapping("/consumer/payment/create")
    public CommonResult<Payment> create(Payment payment) {
        //payment 参数,CommonResult.class返回类型
        return restTemplate.postForObject(PAYMENT_URL + "/payment/create", payment, CommonResult.class);

    }

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

2-4、使用Run Dashboard

第一步:

第二步:

第三步:选择springboot即可

ps：如果上述列表找不到Run Dashboard,则可以在工程目录下找到.idea文件夹下的workspace.xml，在其中相应位置加入以下代码（替换）即可：

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<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>

2-5、工程重构

1、创建模块cloud-api-common

2、导入pom文件

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<?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>springCloud2023</artifactId>
        <groupId>com.jcvv.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloud-api-common</artifactId>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    <dependencies>
        <!--  devtools-->
        <!--        <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>
        <!--    工具包，功能有时间转换...-->
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>5.1.0</version>
        </dependency>
    </dependencies>
</project>

3、抽取entities实体类到该模块中

相关链接：Eureka服务注册中心😶