SpringCloud-Rest Learning Environment Construction: Service Provider

1 Introduction

We will use a Dept department module to make a general case of microservices. The Consumer ( Client ) calls the services provided by the Provider ( Server ) through REST.
Review the previous knowledge of Spring, SpringMVC, Mybatis, etc.
A review of Maven's subcontracting and submodule architecture.

一个简单的Maven模块结构是这样的：
-- app-parent: 一个父项目(app-parent)聚合了很多子项目(app-util\app-dao\app-web...)
  |-- pom.xml
  |
  |-- app-core
  ||---- pom.xml
  |
  |-- app-web
  ||---- pom.xml
  ......

A parent project with multiple Moudule submodules

For the first time, there are 3 sub-modules (Module) under the parent project (Project) of MicroServiceCloud

microservicecloud-api [Encapsulated overall entity/interface/public configuration, etc.]
microservicecloud-consumer-dept-80 [Service Provider]
microservicecloud-provider-dept-8001 [Service Consumer]

2 SpringCloud version selection

Big Release Notes

SpringBoot	SpringCloud	relation
1.2.x	Angel Version (Angel)	Compatible with SpringBoot1.2x
1.3.x	Brixton version (Brixton)	Compatible with SpringBoot1.3x, also compatible with SpringBoot1.4x
1.4.x	Camden Version (Camden)	Compatible with SpringBoot1.4x, also compatible with SpringBoot1.5x
1.5.x	Dalston version (Dalston)	Compatible with SpringBoot1.5x, not compatible with SpringBoot2.0x
1.5.x	Edgware version (Edgewell)	Compatible with SpringBoot1.5x, not compatible with SpringBoot2.0x
2.0.x	Finchley Version (Finchley)	Compatible with SpringBoot2.0x, not compatible with SpringBoot1.5x
2.1.x	Greenwich version (Greenwich)

Actual development version relationship

spring-boot-starter-parent	spring-cloud-dependencles
version number	release date	version number	release date
1.5.2.RELEASE	2017-03	Dalston.RC1	2017-x
1.5.9.RELEASE	2017-11	Edgware.RELEASE	2017-11
1.5.16.RELEASE	2018-04	Edgware.SR5	2018-10
1.5.20.RELEASE	2018-09	Edgware.SR5	2018-10
2.0.2.RELEASE	2018-05	Fomchiey.BULD-SNAPSHOT	2018-x
2.0.6.RELEASE	2018-10	Fomchiey-SR2	2018-10
2.1.4.RELEASE	2019-04	Greenwich.SR1	2019-03

use the last two

3 Create the parent project

Create a new parent project springcloud, remember that Packageing is in pom mode
The main purpose is to define the POM file, and extract the jar packages common to the subsequent sub-modules, similar to an abstract parent class.

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">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.haust</groupId>
    <artifactId>springcloud</artifactId>
    <version>1.0-SNAPSHOT</version>
    <modules>
        <module>springcloud-api</module>
        <module>springcloud-provider-dept-8001</module>
        <module>springcloud-consumer-dept-80</module>
        <module>springcloud-eureka-7001</module>
        <module>springcloud-eureka-7002</module>
        <module>springcloud-eureka-7003</module>
        <module>springcloud-provider-dept-8002</module>
        <module>springcloud-provider-dept-8003</module>
        <module>springcloud-consumer-dept-feign</module>
        <module>springcloud-provider-dept-hystrix-8001</module>
        <module>springcloud-consumer-hystrix-dashboard</module>
        <module>springcloud-zuul-9527</module>
        <module>springcloud-config-server-3344</module>
        <module>springcloud-config-client-3355</module>
        <module>springcloud-config-eureka-7001</module>
        <module>springcloud-config-dept-8001</module>
    </modules>
    <!--打包方式  pom-->
    <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>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>0.2.0.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--springCloud的依赖-->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Greenwich.SR1</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--SpringBoot-->
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>2.1.4.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--数据库-->
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>5.1.47</version>
            </dependency>
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid</artifactId>
                <version>1.1.10</version>
            </dependency>
            <!--SpringBoot 启动器-->
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>1.3.2</version>
            </dependency>
            <!--日志测试~-->
            <dependency>
                <groupId>ch.qos.logback</groupId>
                <artifactId>logback-core</artifactId>
                <version>1.2.3</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>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>

The parent project is springcloud, and there are multiple sub-mudules under it. For details, please refer to the complete code.

springcloud-consumer-dept-80 uses REST to access the controller under springcloud-provider-dept-8001

Such as DeptConsumerController.java

/**
 * @Auther: csp1999
 * @Date: 2020/05/17/22:44
 * @Description:
 */
@RestController
public class DeptConsumerController {
    
    
    /**
     * 理解：消费者，不应该有service层~
     * RestTemplate .... 供我们直接调用就可以了！ 注册到Spring中
     * (地址：url, 实体：Map ,Class<T> responseType)
     * <p>
     * 提供多种便捷访问远程http服务的方法，简单的Restful服务模板~
     */
    @Autowired
    private RestTemplate restTemplate;
    /**
     * 服务提供方地址前缀
     * <p>
     * Ribbon:我们这里的地址，应该是一个变量，通过服务名来访问
     */
    private static final String REST_URL_PREFIX = "http://localhost:8001";
    //private static final String REST_URL_PREFIX = "http://SPRINGCLOUD-PROVIDER-DEPT";
    /**
     * 消费方添加部门信息
     * @param dept
     * @return
     */
    @RequestMapping("/consumer/dept/add")
    public boolean add(Dept dept) {
    
    
        // postForObject(服务提供方地址(接口),参数实体,返回类型.class)
        return restTemplate.postForObject(REST_URL_PREFIX + "/dept/add", dept, Boolean.class);
    }
    /**
     * 消费方根据id查询部门信息
     * @param id
     * @return
     */
    @RequestMapping("/consumer/dept/get/{id}")
    public Dept get(@PathVariable("id") Long id) {
    
    
        // getForObject(服务提供方地址(接口),返回类型.class)
        return restTemplate.getForObject(REST_URL_PREFIX + "/dept/get/" + id, Dept.class);
    }
    /**
     * 消费方查询部门信息列表
     * @return
     */
    @RequestMapping("/consumer/dept/list")
    public List<Dept> list() {
    
    
        return restTemplate.getForObject(REST_URL_PREFIX + "/dept/list", List.class);
    }
}

To use RestTemplete, you need to put it into the Spring container first

ConfigBean.java

@Configuration
public class ConfigBean {
    
    
    //@Configuration -- spring  applicationContext.xml
    //配置负载均衡实现RestTemplate
    // IRule
    // RoundRobinRule 轮询
    // RandomRule 随机
    // AvailabilityFilteringRule ： 会先过滤掉，跳闸，访问故障的服务~，对剩下的进行轮询~
    // RetryRule ： 会先按照轮询获取服务~，如果服务获取失败，则会在指定的时间内进行，重试
    @Bean
    public RestTemplate getRestTemplate(){
    
    
        return new RestTemplate();
    }
}

The mapper interface of springcloud-provider-dept-8001 calls the pojo under the springcloud-api module. You can use the pom file of springcloud-provider-dept-8001 to import the dependencies of the springcloud-api module:

<!--我们需要拿到实体类，所以需要配置api module-->
        <dependency>
            <groupId>com.kwok</groupId>
            <artifactId>springcloud-api</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>

The pom.xml of springcloud-consumer-dept-80 and springcloud-provider-dept-8001 is basically the same as the dependency under the parent project. You can directly read the complete code without adding repeated notes.