SpringCloud-2.0（4. Rest工程构建）

Posted 2021-06-30 ABin-阿斌

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文章目录

2 . 热部署 Devtools
3 . 系统重构
4 . 项目目录

Rest微服务工程构建

我们现在要构建的是一个支付订单的模块

1 . 单个模块的建立步骤

思路：
- 新建模块
- 修改 POM
- 编写 YAML
- 配置主启动类
- 编写业务类

2 . 构建服务提供者模块

端口号：8001

新建一个 Maven 模块： cloud-provider-payment-8001

编写 POM 文件，引入依赖

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

编写 YML 配置文件，application.yml

# 配置端口号
server:
  port: 8001

spring:
  # 配置服务名称
  application:
    name: cloud-payment-service
  # 配置数据源
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: org.gjt.mm.mysql.Driver
    url: jdbc:mysql://localhost:3306/spring_cloud_01?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=UTC
    username: root
    password: 123456

# 配置 Mybatis 的包扫描
mybatis:
  mapperLocations: classpath:mapper/*.xml
  type-aliases-package: com.demo.springcloud.pojo

新建一个主启动类，PaymentMain8001

@SpringBootApplication
public class PaymentMain8001 {
    public static void main(String[] args) {
        SpringApplication.run(PaymentMain8001.class, args);
    }
}

业务类

建立 SQL 表：自己插入点数据

CREATE TABLE `payment` (
  `id` bigint(20) NOT NULL COMMENT '编号',
  `serial` varchar(200) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci DEFAULT NULL COMMENT '流水号',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

编写订单的实体类：Payment

@Data
@AllArgsConstructor
@NoArgsConstructor
@Accessors(chain = true) /** Lombok链式编程 */
public class Payment implements Serializable {
	/** 编号 */
	private Long id;
    
	/** 流水号 */
	private String serial;
}

编写用于封装返回数据的实体类：CommonResult

@Data
@AllArgsConstructor
@NoArgsConstructor
public class CommonResult<T> {
    /** 返回的结果代码 */
    private Integer code;

    /** 返回的结果的说明 */
    private String message;

    /** 得到的结果集 */
    private T data;

    /** 自定义一个没有结果集的情况的构造 */
    public CommonResult(Integer code, String message){
        this(code, message, null);
    }
}

Dao：PaymentMapper

@Mapper
public interface PaymentMapper {
	public int create(Payment payment);
	public Payment getPaymentById(@Param("id") Long id);
}

Mapper : PaymentMapper.xml

<?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.demo.springcloud.dao.PaymentMapper">

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

Service：PaymentService

@Mapper
public interface PaymentService {
	public int create(Payment payment);
	public Payment getPaymentById(@Param("id") Long id);
}

ServiceImpl :PaymentServiceImpl

@Service
public class PaymentServiceImpl implements PaymentService {
    @Resource
    private PaymentDao paymentDao;
    public int create(Payment payment){
        return paymentDao.create(payment);
    }
    public Payment getPaymentById( Long id){
        return paymentDao.getPaymentById(id);
    }
}

Controller ：PaymentController

@RestController
@Slf4j
public class PaymentController {

    @Resource
    private PaymentService paymentService;

    @PostMapping(value = "/payment/create")
    // 这个的 @RequestBody 在测试 provider 的时候可以不写
    // 但是通过 RestTemlate 远程访问该方法时，就要加上了，不然识别不到该参数
    public CommonResult create(@RequestBody Payment payment){
       int result = paymentService.create(payment);
       log.info("*****插入结果："+result);
       if (result>0){  //成功
           return new CommonResult(200,"插入数据库成功",result);
       }else {
           return new CommonResult(444,"插入数据库失败",null);
       }
    }
    @GetMapping(value = "/payment/get/{id}")
    public CommonResult getPaymentById(@PathVariable("id") Long id){
        Payment payment = paymentService.getPaymentById(id);
        log.info("*****查询结果："+payment);
        if (payment!=null){  //说明有数据，能查询成功
            return new CommonResult(200,"查询成功",payment);
        }else {
            return new CommonResult(444,"没有对应记录，查询ID："+id,null);
        }
    }
}

注意： 这个的 @RequestBody 在测试 provider 的时候可以不写，但是通过 RestTemlate 远程访问该方法时，就要加上了，不然识别不到该参数

测试 provider 模块

3 . 构建服务消费者模块

端口号：80

新建一个 Maven 项目： cloud-consumer-order-80
修改 POM 文件

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

编写 YML
```
server:
  port: 80
```

配置主启动类

@SpringBootApplication
public class orderMain80 {
    public static void main(String[] args) {
        SpringApplication.run(orderMain80.class, args);
    }
}

业务类：
- 实体类，先把服务端的实体类复制过来
RestTemplate 大致概述：
- 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 服务的模板类，是 Spring 提供的用于访问 Rest 服务的客户端模板工具

ApplicationContextConfig配置类

@Configuration
public class ApplicationContextConfig {
    /** 将 RestTemplate 注入 Bean */
    @Bean
    public RestTemplate getRestTemplate(){
        return new RestTemplate();
    }
}

Controller ：OrderController

@RestController
@Slf4j
public class OrderController {

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

    @Resource
    private RestTemplate restTemplate;

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

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

测试 consumer 模块

2 . 热部署 Devtools

添加 devtools 依赖

<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-devtools -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <scope>runtime</scope>
        <optional>true</optional>
    </dependency>

在父工程的 POM 中配置插件

<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>

开启自动编译的选项
更新值
快捷键：Ctrl + Shift + Alt + /
重启 IDEA

3 . 系统重构

在上面的 provider 和 consumer 中都重复的部分，为减少代码冗余，需要进行重构、提出共用部分
新建一个工程：cloud-api-commons
- 这个工程中，不但可以存放重复的代码，还可以存放接口、工具类…… 该工程不对外暴露

修改 POM 文件

<dependencies>
    <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-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>
    <!--轻量级的 JAVA 工具包-->
    <!-- https://mvnrepository.com/artifact/cn.hutool/hutool-all -->
    <dependency>
        <groupId>cn.hutool</groupId>
        <artifactId>hutool-allSpringCloud-2.0（5. 服务注册发现 - Eureka）
 SpringCloud-2.0-周阳（21. Sentinel 环境搭建）
 SpringCloud-2.0-周阳（13. 分布式配置中心 - SpringCloud Config）
 SpringCloud-2.0 （9. 负载均衡 - OpenFeign）
 SpringCloud-2.0-周阳：（12. 服务网关 - Gateway）
 SpringCloud-2.0-周阳（24. 分布式事务 - Seata）