spring cloud组件搭建：一（eureka）

eureka与zookeeper同样都可以作为spring cloud的注册组件，但考虑到分布式领域的CAP理论、C（Consistency数据一致性），A（Availability服务可用性）、P（Partition Tolerance分区容错性）由于C与A不能共存
在保证用户可用的基本前提下，eureka就显得比zookeeper更加适合作为注册中心
下面先来创建一个聚合工程
表的信息

book.png

先创建服务的提供者provider
pom文件如下

<?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>

    <artifactId>service-provider</artifactId>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.2.RELEASE</version>
    </parent>

    <dependencies>
        <!-- Add typical dependencies for a web application -->

        <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>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.11</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.0</version>
        </dependency>

        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-spring-boot-starter</artifactId>
            <version>2.0.4</version>
        </dependency>

        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper</artifactId>
            <version>3.3.9</version>
        </dependency>
    </dependencies>

</project>

yml文件


server:
  port: 8082
  sessionTimeout: 20
  servlet:
    context-path: /provider


spring:
  datasource:
      driver-class-name: com.mysql.jdbc.Driver
      url : jdbc:mysql://localhost:3306/ampmysql?serverTimezone=GMT%2B8
      username : root
      password : 123
      max-active: 1
      max-idle: 1
      min-idle: 0
#logging:
#  config: classpath:config/logback.xml
#
#mybatis:
#        mapper-locations: classpath:mappers/*.xml

#显示jpa的执行sql
mybatis:
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

实体类pojo

import lombok.Data;

import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import java.io.Serializable;

@Data
@Table(name="bookinfo")
public class BookInfo implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private  String id;
    private String title;
    private  String author;


}

映射mapper

import com.flash.pojo.BookInfo;
import tk.mybatis.mapper.common.Mapper;

@org.apache.ibatis.annotations.Mapper
public interface BookInfoMapper extends Mapper<BookInfo> {
}

service接口

import com.flash.pojo.BookInfo;

public interface BookInfoService {

  public   BookInfo  findById(int id);
}

接口实现类

import com.flash.mapper.BookInfoMapper;
import com.flash.pojo.BookInfo;
import com.flash.service.BookInfoService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

@Service
public class BookInfoServiceImpl implements BookInfoService {

    @Resource
    private  BookInfoMapper bookInfoMapper;

    @Override
    public BookInfo findById(int id) {
        return bookInfoMapper.selectByPrimaryKey(id);
    }
}

controller层

import com.flash.pojo.BookInfo;
import com.flash.service.impl.BookInfoServiceImpl;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

@RestController
public class BookInfoController {

    @Resource
    private  BookInfoServiceImpl bookInfoServiceImpl;

    @RequestMapping("/findById/{id}")
    public BookInfo findById(@PathVariable(name="id") int id){

        return  bookInfoServiceImpl.findById(id);
    }
}

启动类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import tk.mybatis.spring.annotation.MapperScan;

@SpringBootApplication
@MapperScan(basePackages = "com.flash.mapper")
public class ProviderApp {
    public static void main(String[] args) {

        SpringApplication.run(ProviderApp.class,args);
    }
}

再来创建服务的消费者consumer
pom文件基本一致

<?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>

    <artifactId>server-consumer</artifactId>

    <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.0.2.RELEASE</version>
</parent>

<dependencies>

<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>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-logging</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-actuator</artifactId>
</dependency>

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

</project>

pojo类，service层基本一致

import lombok.Data;



@Data
public class BookInfo {

    private  String id;
    private String title;
    private  String author;


}

import com.flash.pojo.BookInfo;

public interface BookInfoService {

  public   BookInfo  findById(int id);
}

接口实现

import com.flash.pojo.BookInfo;
import com.flash.service.BookInfoService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

import javax.annotation.Resource;
import java.awt.print.Book;

@Service
public class BookInfoServiceImpl implements BookInfoService {


    @Autowired
    private RestTemplate restTemplate;

    @Override
    public BookInfo findById(int id) {
        BookInfo bookInfo =
                restTemplate.getForObject("http://localhost:8081/provider/findById/"+id,BookInfo.class);

        System.out.println(bookInfo);

        return bookInfo;
    }
}

使用rest方式调用

测试类

import com.flash.ComsumerApp;
import com.flash.service.BookInfoService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import javax.annotation.Resource;

@RunWith(SpringRunner.class)
@SpringBootTest(classes= ComsumerApp.class)
public class Test01 {

    @Resource
    private  BookInfoService bookInfoService;

    @Test
    public void test(){
        bookInfoService.findById(1);
    }
}

编写启动类ComsumerApp

启动提供者，然后测试

result.png

下面开始操作eureka
重新创建一个聚合工程
聚合工程的pom来做依赖的版本管理
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>org.example</groupId>
    <artifactId>cloudparent</artifactId>
    <version>1.0-SNAPSHOT</version>
    <modules>
        <module>eureka-server</module>
        <module>eureka-client-provider</module>
        <module>eureka-client-consumer</module>
        <module>eureka-client-provider02</module>
        <module>cloud-feign</module>
    </modules>
    <packaging>pom</packaging>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Finchley.RC1</spring-cloud.version>
    </properties>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.2.RELEASE</version>
    </parent>




    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-depndencies</artifactId>
                <version>${spring.cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>

        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

<packaging>pom</packaging>这个地方不要错

创建注册中心eureka
pom文件

<?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>cloudparent</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    
    <modelVersion>4.0.0</modelVersion>

    <artifactId>eureka-server</artifactId>


    <dependencies>

        <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-eureka-client -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
            <version>2.0.2.RELEASE</version>
        </dependency>


        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
    </dependencies>

</project>

yml文件


server:
  port: 8888




spring:
  application:
    name: eureka-server #注册中心命名




eureka:
  client:
    service-url:
      defaultZone: http://127.0.0.1:8888/eureka
#  server:
#    enable-self-preservation: false#关闭自我保护模式
#    eviction-interval-timer-in-ms: 1000扫描失效服务的间隔时间

编写启动类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;

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

然后启动

编写启动类的代码与上面一样
除启动类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import tk.mybatis.spring.annotation.MapperScan;

@SpringBootApplication
@MapperScan(basePackages = "com.flash.mapper")
@EnableEurekaClient
public class ProviderApp {
    public static void main(String[] args) {

        SpringApplication.run(ProviderApp.class,args);
    }
}

需要添加@EnableEurekaClient客户端注解

pom文件

<?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>cloudparent</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>eureka-client-provider</artifactId>


    <dependencies>
        <!-- Add typical dependencies for a web application -->

        <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>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
        </dependency>

        <!-- 加入actuator依赖后，应用启动后会创建一些基于Web的Endpoint -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.11</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.0</version>
        </dependency>

        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-spring-boot-starter</artifactId>
            <version>2.0.4</version>
        </dependency>

        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper</artifactId>
            <version>3.3.9</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
            <version>2.0.2.RELEASE</version>
        </dependency>
    </dependencies>
</project>

yml文件


server:
  port: 8081
  sessionTimeout: 20
  servlet:
    context-path: /provider


spring:
  datasource:
      driver-class-name: com.mysql.jdbc.Driver
      url : jdbc:mysql://localhost:3306/ampmysql?serverTimezone=GMT%2B8
      username : root
      password : 123
      max-active: 1
      max-idle: 1
      min-idle: 0
  application:
    name: eureka-client-provider




mybatis:
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

eureka:
  client:
    service-url:
      defaultZone: http://127.0.0.1:8888/eureka
#      defaultZone: http://127.0.0.1:8888/eureka,http://127.0.0.1:8889/eureka
  instance:
    prefer-ip-address: true
    ip-address: 127.0.0.1

然后启动

下面编写服务的消费者
消费者pom文件

<?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>cloudparent</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>eureka-client-consumer</artifactId>

    <dependencies>
        <!-- Add typical dependencies for a web application -->

        <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>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
        </dependency>

        <!-- 加入actuator依赖后，应用启动后会创建一些基于Web的Endpoint -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

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


        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
            <version>2.0.2.RELEASE</version>
        </dependency>

       

       

    </dependencies>
</project>

yml文件


server:
  port: 8082


spring:
  application:
    name: eureka-client-consumer





eureka:
  client:
    service-url:
#      defaultZone: ttp://127.0.0.1:8888/eureka,http://127.0.0.1:8889/eureka
      defaultZone: http://127.0.0.1:8888/eureka

消费者的接口实现

package com.flash.service.impl;

import com.flash.pojo.BookInfo;
import com.flash.service.BookInfoService;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixProperty;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
import org.springframework.cloud.netflix.ribbon.RibbonLoadBalancerClient;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

import javax.annotation.Resource;
import java.util.List;

@Service
public class BookInfoServiceImpl implements BookInfoService {

   

    @Autowired
    private RestTemplate restTemplate;

    @Resource
    DiscoveryClient discoveryClient;

 

    @Override
  
    public BookInfo findById(int id) {
        BookInfo bookInfo =
                restTemplate.getForObject("http://localhost:8081/provider/findById/"+id,BookInfo.class);

     

       
        return bookInfo;
    }


  
}

创建RestTemplateConfig配置类

import com.netflix.loadbalancer.IRule;
import com.netflix.loadbalancer.RandomRule;
import com.netflix.loadbalancer.RetryRule;


import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.client.OkHttp3ClientHttpRequestFactory;
import org.springframework.web.client.RestTemplate;

@Configuration
public class RestTemplateConfig {

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

   



}

启动类

package com.flash;

import com.flash.config.RestTemplateConfig;
import com.netflix.loadbalancer.IRule;
import com.netflix.loadbalancer.RandomRule;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.netflix.hystrix.EnableHystrix;
import org.springframework.cloud.netflix.ribbon.RibbonClient;
import org.springframework.context.annotation.Bean;

@SpringBootApplication
@EnableEurekaClient //客户端
public class ConsumApp {
    public static void main(String[] args) {
        SpringApplication.run(ConsumApp.class,args);

    }

}

启动
再次查看eureka页面信息

然后调用一把消费者
查看结果

ok！搞定收工

spring cloud组件搭建：一（eureka）

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