【Spring】SpringCloudの環境構築（restTemplate+ribbon）-526互联

参考URL：<https://zhuanlan.zhihu.com/p/272663162?utm_id=0>

■紹介

SpringCloudの初心者に向け、簡単な手順を作成する。Eurekaサーバを利用して、「server」を立って。それにして、

提供者(provider)と消費者(consumer)を全て「server」に導入して、管理する。消費者(consumer)の内部に、ribbonの技術を利用して、

提供者(provider)を呼びます。三つのプロジェクトを別々に構築できるし、「server」で管理できる。

■構造

■説明

・spring-cloud-eureka-server：子項目（Module）、Eurekaのサービスを提供する

・spring-cloud-service-provider：子項目（Module）、Eurekaに導入し、提供者としてサービスを提供

・spring-cloud-client-ribbon：子項目（Module）、Eurekaに導入し、消費者として、内部で提供者に呼ぶ

■「POM.xml」の配置

・spring-cloud-eureka-server

<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>spring-cloud-eureka-server</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>spring-cloud-server</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.7</maven.compiler.source>
    <maven.compiler.target>1.7</maven.compiler.target>
    <!-- SpringBoot1.5.x -->
    <spring.cloud.dependencies.version>Edgware.SR5</spring.cloud.dependencies.version>
  </properties>

  <!-- 引入SpringBoot-Parent项目 -->
  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.7.RELEASE</version>
  </parent>

  <dependencies>
    <!-- Cloud Server依赖 -->
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
    </dependency>
  </dependencies>

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

</project>

pom.xml

・spring-cloud-service-provider

<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>spring-cloud-service-provider</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>spring-cloud-service</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.7</maven.compiler.source>
    <maven.compiler.target>1.7</maven.compiler.target>
    <spring.cloud.dependencies.version>Edgware.SR5</spring.cloud.dependencies.version>
  </properties>

  <!-- 引入SpringBoot-Parent项目 -->
  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.7.RELEASE</version>
  </parent>

  <dependencies>
    <!-- Cloud Client依赖 -->
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
    </dependency>
  </dependencies>

  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-dependencies</artifactId>
        <version>${spring.cloud.dependencies.version}</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
    </dependencies>
  </dependencyManagement>
</project>

pom.xml

・spring-cloud-client-ribbon

<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>spring-cloud-client-consumer</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>spring-cloud-client-ribbon</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.7</maven.compiler.source>
    <maven.compiler.target>1.7</maven.compiler.target>
    <spring.cloud.dependencies.version>Edgware.SR5</spring.cloud.dependencies.version>
  </properties>

  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.7.RELEASE</version>
  </parent>

  <dependencies>
    <!-- Cloud Client依赖 -->
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
    </dependency>
    <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-starter-ribbon</artifactId>
    </dependency>
  </dependencies>

  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-dependencies</artifactId>
        <version>${spring.cloud.dependencies.version}</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
    </dependencies>
  </dependencyManagement>
</project>

pom.xml

■「application.xml」の配置

・spring-cloud-eureka-server

server:
  port: 8700

eureka:
  instance:
    hostname: localhost
  client:
    register-with-eureka: false
    fetch-registry: false
    service-url:
      defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka
#如果需要开通多个端口时，使用下面方式
#      defaultZone: http://localhost:8699/eureka,http://localhost:8698/eureka
spring:
  application:
    name: eureka-server

application.xml

・spring-cloud-service-provider

server:
  port: 8701

eureka:
  instance:
    hostname: localhost

  client:
    service-url:
      defaultZone: http://${eureka.instance.hostname}:8700/eureka

spring:
  application:
    name: eureka-provider

application.xml

・spring-cloud-client-ribbon

server:
  port: 8702

eureka:
  instance:
    hostname: localhost
  client:
    service-url:
      defaultZone: http://${eureka.instance.hostname}:8700/eureka

spring:
  application:
    name: eureka-consumer

eureka-provider:
  ribbon:
    ActiveConnectionsLimit: 1000

application.xml

■「XXXApplication.java」の配置

・spring-cloud-eureka-server

package org.example;

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

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

CloudServerApplication.java

・spring-cloud-service-provider

package org.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

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

CloudServiceProviderApplication.java

・spring-cloud-client-ribbon

package org.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

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

CloudClientRibbonApplication.java

■「controller」の作成

・spring-cloud-service-provider(提供者側)

package org.example.controller;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/provider")
public class ProviderController {

    @RequestMapping("/hello")
    public String helloWorld(String str){
        System.out.println("str:"+str);
        return "parameter:"+str;
    }
}

ProviderController.java

・spring-cloud-client-ribbon(消費者側)

package org.example.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@RestController
@RequestMapping("/consumer")
public class ConsumerController {

    @Autowired
    private LoadBalancerClient loadBalancerClient;

    @Autowired
    private RestTemplate restTemplate;

    @RequestMapping("/hello")
    public String helloWorld(@RequestParam String str){
        System.out.println("str:"+str);
        String forObject = "";
        try{
            //第一种(需要bean注入，通过用Service名调用)
            forObject = restTemplate.getForObject("http://eureka-provider/provider/hello?str="+str,String.class);

            //第二种（只能通过IP+端口调用）
            //forObject = new RestTemplate().getForObject("http://localhost:8701/provider/hello?str="+str,String.class);

            //第三种（通过解析Service名转换IP+端口调用）
            //ServiceInstance serviceInstance =loadBalancerClient.choose("eureka-provider");
            //forObject = new RestTemplate().getForObject("http://"+serviceInstance.getHost()+":"+serviceInstance.getPort()+"/provider/hello?str="+str, String.class);

        }catch (Exception ex){
            throw ex;
        }
        return forObject;
    }
}

ConsumerController.java

package org.example.beans;

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

@Configuration
public class Beans {

    @Bean
    @LoadBalanced
    public RestTemplate getRestTemplate(){
        return new RestTemplate();
    }
}