Ribbon 负载均衡

四：Ribbon 负载均衡

分布式高并发

Spring Cloud 提供的一种负载均衡的解决方案，Ribbon 是Netfix发布的负载均衡器，springcloud Ribbon 的使用同样要结合Eureka Server

负载均衡算法：轮询、随机、加权轮询、加权随机

1.创建模块，配置环境

<?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>springCloud01</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>ribbon</artifactId>

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

2.application.yml

server:
  port: 8040
spring:
  application:
    name: ribbon
eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/
  instance:
    prefer-ip-address: true

3.创建启动类：

package com.southwind;

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

@SpringBootApplication
public class ribbonApplication {
    public static void main(String[] args) {
        SpringApplication.run(ribbonApplication.class,args);
    }
    @Bean
    @LoadBalanced
    public RestTemplate restTemplate(){
        return new RestTemplate();
    }
}

4.实体类：

package com.southwind.entity;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Student {
    private Integer id;
    private String name;

}

5.controller

package com.southwind.controller;

import com.southwind.entity.Student;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import java.util.Collection;

@RestController
@RequestMapping("/ribbon")
public class RibbonHandler {
    @Autowired
    private RestTemplate restTemplate;

    @GetMapping("/findall")
    public Collection<Student> findall(){
        return restTemplate.getForObject("http://provider/provider/findall",Collection.class);
    }
    @GetMapping("/index")
    public String index(){
        return restTemplate.getForObject("http://consumer/consumer/index",String.class);
    }
}

网关加不了逻辑，只是简单的路由的映射