java框架之SpringCloud(2)-Rest微服务案例

在上一章节已经对微服务与 SpringCloud 做了介绍，为方便后面学习，下面以 Dept 部门模块为例做一个微服务通用 Demo —— Consumer 消费者（Client） 通过 REST 调用 Provider 提供者（Server）提供的服务，后续学习在该 Demo 基础上集成新功能。

环境

IDE：IDEA

SpringBoot 版本：1.5.20.RELEASE

SpringCloud 版本：Dalston.RELEASE

构建工具：Maven

开工

父工程构建

新建工程，打包方式为 pom ，工程名为 "microservicecloud" 依赖如下：

<?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>zze.springcloud</groupId>
  <artifactId>microservicecloud</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>pom</packaging>
  <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>
  </properties>

  <dependencyManagement>
    <dependencies>
      <!--Spring Cloud-->
      <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-dependencies</artifactId>
        <version>Dalston.RELEASE</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
      <!--Spring Boot-->
      <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-dependencies</artifactId>
        <version>1.5.20.RELEASE</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
      <!--Mysql Connector-->
      <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.47</version>
      </dependency>
      <!--DataSource-->
      <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>1.0.31</version>
      </dependency>
      <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
        <version>1.3.0</version>
      </dependency>
      <!--log-->
      <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-core</artifactId>
        <version>1.2.3</version>
      </dependency>
      <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>${log4j.version}</version>
      </dependency>
      <!--test-->
      <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>${junit.version}</version>
      </dependency>
    </dependencies>
  </dependencyManagement>
</project>

pom.xml

下面新建的子工程的父工程都为 microservicecloud ，打包方式都为 jar。

公共子模块

新建名为 "microservicecloud-api" 的子工程，依赖如下：

<?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>microservicecloud</artifactId>
        <groupId>zze.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
        <relativePath>../microservicecloud/pom.xml</relativePath>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <description>封装整体的 entity 、接口、公共配置等</description>

    <artifactId>microservicecloud-api</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
    </dependencies>
</project>

pom.xml

新建部门 Entity：

package zze.springcloud.entities;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.experimental.Accessors;

import java.io.Serializable;

@AllArgsConstructor
@NoArgsConstructor
@Data
@Accessors(chain = true)
public class Dept implements Serializable {
    private Long deptNo; // 主键
    private String deptName; // 部门名称
    private String dbSource; // 来自哪个数据库，因为微服务架构中一个服务可以对应一个数据库，信息可被存储到不同数据库
}

zze.springcloud.entities.Dept

微服务Provider

新建名为 "microservicecloud-provider-dept-8001" 的子工程作为微服务提供者，依赖如下：

<?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>microservicecloud</artifactId>
        <groupId>zze.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
        <relativePath>../microservicecloud/pom.xml</relativePath>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <description>部门微服务提供者</description>
    <artifactId>microservicecloud-provider-dept-8001</artifactId>

    <dependencies>
        <dependency>
            <groupId>zze.springcloud</groupId> <!--引入自定义的 api 通用包，可以使用 Dept 部门 Entity-->
            <artifactId>microservicecloud-api</artifactId>
            <version>${project.version}</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jetty</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
        <!--修改后立即生效，热部署-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>springloaded</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>
    </dependencies>
</project>

pom.xml

初始化数据库表结构及数据：

DROP DATABASE IF EXISTS springcloud_8001;
CREATE DATABASE springcloud_8001 CHARACTER SET UTF8;
USE springcloud_8001;

CREATE TABLE dept
(
  dept_no   BIGINT NOT NULL PRIMARY KEY AUTO_INCREMENT,
  dept_name ),
  db_source )
);

INSERT INTO dept(dept_name, db_source)
VALUES ('开发部', DATABASE());
INSERT INTO dept(dept_name, db_source)
VALUES ('人事部', DATABASE());
INSERT INTO dept(dept_name, db_source)
VALUES ('财务部', DATABASE());
INSERT INTO dept(dept_name, db_source)
VALUES ('市场部', DATABASE());
INSERT INTO dept(dept_name, db_source)
VALUES ('运维部', DATABASE());

SELECT * FROM dept;

dept.sql

配置数据源及 mybatis 相关，指定服务端口为 8001：

server:
  port: 8001

mybatis:
  config-location: classpath:mybatis/mybatis.cfg.xml # mybatis 配置文件路径
  type-aliases-package: zze.springcloud.entities # 所有 Entity 别名类所在包
  mapper-locations:
    - classpath:mybatis/mapper/**/*.xml # mapper 映射文件

spring:
  application:
    name: microservicecloud-dept # 当前微服务名称
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource # 数据源操作类型
    driver-class-name: org.gjt.mm.mysql.Driver # mysql 驱动包
    url: jdbc:mysql:///springcloud_8001 # 数据库连接 root
    username: root
    password: root
    dbcp2:
      min-idle: 5 # 数据库连接池的最小维持连接数
      initial-size: 5 # 初始化连接数
      max-total: 5 # 最大连接数
      max-wait-millis: 200 # 等待连接获取的最大超时时间

application.yml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <settings>
        <setting name="cacheEnabled" value="true"/> <!--二级缓存开启-->
        <!--启用驼峰命名，表字段 user_name 可映射到 userName -->
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
</configuration>

mybatis/mybatis.cfg.xml

编写部门 Dao：

package zze.springcloud.dao;

import org.apache.ibatis.annotations.Mapper;
import zze.springcloud.entities.Dept;

import java.util.List;

@Mapper
public interface DeptDao {
    public boolean addDept(Dept dept);

    public Dept findById(Long id);

    public List<Dept> findAll();
}

zze.springcloud.dao.DeptDao

<?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="zze.springcloud.dao.DeptDao">
    <select id="findById" resultType="Dept" parameterType="Long">
        select dept_no,dept_name,db_source from dept where dept_no=#{deptNo};
    </select>

    <select id="findAll" resultType="Dept">
        select dept_no,dept_name,db_source from dept;
    </select>

    <select id="addDept" parameterType="Dept">
        insert into dept(dept_name,db_source) values(#{deptName},DATABASE());
    </select>
</mapper>

mybatis/mapper/DeptMapper.xml

编写部门 Service：

package zze.springcloud.service;

import zze.springcloud.entities.Dept;

import java.util.List;

public interface DeptService {
    public boolean add(Dept dept);

    public Dept get(Long id);

    public List<Dept> list();
}

zze.springcloud.service.DeptService

package zze.springcloud.service.impl;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import zze.springcloud.dao.DeptDao;
import zze.springcloud.entities.Dept;
import zze.springcloud.service.DeptService;

import java.util.List;
@Service
public class DeptServiceImpl implements DeptService {
    @Autowired
    private DeptDao deptDao;

    @Override
    public boolean add(Dept dept) {
        return deptDao.addDept(dept);
    }

    @Override
    public Dept get(Long id) {
        return deptDao.findById(id);
    }

    @Override
    public List<Dept> list() {
        return deptDao.findAll();
    }
}

zze.springcloud.service.impl.DeptServiceImpl

编写部门 Controller：

package zze.springcloud.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import zze.springcloud.entities.Dept;
import zze.springcloud.service.DeptService;

import java.util.List;

@RestController
@RequestMapping("/dept")
public class DeptController {

    @Autowired
    private DeptService deptService;

    @PostMapping("/add")
    public boolean add(@RequestBody Dept dept) {
        return deptService.add(dept);
    }

    @GetMapping("/get/{id}")
    public Dept get(@PathVariable Long id) {
        return deptService.get(id);
    }

    @GetMapping("/list")
    public List<Dept> list() {
        return deptService.list();
    }
}

zze.springcloud.controller.DeptController

编写主启动类：

package zze.springcloud;

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

@SpringBootApplication
public class Application_8001 {

    public static void main(String[] args) {
        SpringApplication.run(Application_8001.class, args);
    }
}

zze.springcloud.Application_8001

测试：

运行主启动类，访问 http://localhost:8001/dept/list：

test

微服务Consumer

新建名为 "microservicecloud-consumer-dept-80" 的子工程作为微服务提供者，依赖如下：

<?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>microservicecloud</artifactId>
        <groupId>zze.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
        <relativePath>../microservicecloud/pom.xml</relativePath>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <description>部门微服务消费者</description>

    <artifactId>microservicecloud-consumer-dept-80</artifactId>

    <dependencies>
        <dependency>
            <groupId>zze.springcloud</groupId>
            <artifactId>microservicecloud-api</artifactId>
            <version>${project.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!--修改后立即生效，热部署-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>springloaded</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>
    </dependencies>

</project>

pom.xml

指定服务端口为 80：

server:
  port: 80

application.yml

新建配置类，注册 RestTemplate bean：

package zze.springcloud.cfgbeans;

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

@Configuration
public class ConfigBean {
    @Bean
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }
}

zze.springcloud.cfgbeans.ConfigBean

新建 Controller，通过 RestTemplate bean 使用 Provider 提供的服务：

package zze.springcloud.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.client.RestTemplate;
import zze.springcloud.entities.Dept;

import java.util.List;

@RestController
@RequestMapping("/consumer/dept")
public class DeptController {
    // 微服务 Provider 的服务地址
    private final static String REST_URL_PREFIX = "http://127.0.0.1:8001";

    @Autowired
    private RestTemplate restTemplate;

    @PostMapping("/add")
    public boolean add(@RequestBody Dept dept) {
        return restTemplate.postForObject(REST_URL_PREFIX + "/dept/add", dept,Boolean.class);
    }

    @GetMapping("/get/{id}")
    public Dept get(@PathVariable Long id){
        return restTemplate.getForObject(REST_URL_PREFIX + "/dept/get/" + id, Dept.class);
    }

    @GetMapping("/list")
    public List<Dept> list(){
        return restTemplate.getForObject(REST_URL_PREFIX + "/dept/list", List.class);
    }
}

zze.springcloud.controller.DeptController

编写主启动类：

package zze.springcloud;

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

@SpringBootApplication
public class Application_80 {

    public static void main(String[] args) {
        SpringApplication.run(Application_80.class, args);
    }
}

zze.springcloud.Application_80

测试：

1、先启动部门微服务提供者即 microservicecloud-provider-dept-8001 工程。
2、再启动部门微服务消费者即 microservicecloud-consumer-dept-80 工程，访问 http://localhost/consumer/dept/list：

test