spring-cloud-使用Ribbon实现负载均衡

必看提示以及声明:

请合理选择适合自己使用的方式,因个人原因产生的问题,均与博主无关

大致流程

1:确认注册中心已启动

2:确认客户端已启动(上节是2222端口为服务端,我们可以创建并配置一模一样的端口号为2223的客户端)

3:开发工具创建maven项目(博主这里选择与客户端一样的创建流程,稍后修改下pom)

4:配置pom,并创建controller

图片暂无

准备

1:启动注册中心(博主这里端口号为:1111)以及2222端口2223端口的客户端

2:idea工具

具体流程

1:启动注册中心,访问http://localhost:1111,出现注册中心页面

2:启动客户端,访问http://localhost:1111,客户端已注册

3:打开idea,选择file->new->project->Spring Initializr,在弹出页面填写信息,默认就好,然后选择Cloud Discovery->Eureka client,最后finish

4:在启动类**Application,添加服务注释,使用@EnableDiscoveryClient注解在将其注册在注册中心。并且提供一个返回RestTemplate的bean实例,使用@LoadBalanced注解对这个实例进行负载均衡这样,使用这个实例去获取服务的时候,就会帮我们进行负载均衡了。

代码如下

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.circuitbreaker.EnableCircuitBreaker;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;

@SpringBootApplication
@EnableDiscoveryClient
@EnableCircuitBreaker
public class Client2333Application {

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

 public static void main(String[] args) {
     SpringApplication.run(Client2333Application.class, args);
 }
}

5:在application.properties中配置如下:

spring.application.name=ribbon-consumer
server.port=2333
eureka.client.serviceUrl.defaultZone=http://localhost:1111/eureka/

6:最后修改pom文件
按照步骤通过idea 修改的pom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>com.vf.eureka</groupId>
    <artifactId>client-2333</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>client-2333</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <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.SR1</spring-cloud.version>
    </properties>

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

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-hystrix</artifactId>
            <version>1.4.2.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.netflix.hystrix</groupId>
            <artifactId>hystrix-core</artifactId>
            <version>1.5.12</version>
        </dependency>
    </dependencies>

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

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


</project>

7:创建文件 ConsumerController
创建了bean实例,我们就可以通过@Autowired来获取这个RestTemplate了,并且使用这个实例去调用服务。

@Autowired
private ComputeService computeService;

@RequestMapping(value = "/add", method = RequestMethod.GET)
public String add() {
    return computeService.addService();
}

8:最后在启动类**Application右键启动,访问配置的地址:http://localhost:2333/add
即可看到 两个客户端分别输出信息,但是页面只有一个回复

碰到的问题以及解决方法

参考文章

https://blog.csdn.net/a60782885/article/details/69267934