ribbon源码全流程分析

ribbon源码分析：https://www.processon.com/view/link/615166bc079129511c8f2b88

    4.0.0

    
        org.springframework.boot
        spring-boot-starter-parent
        2.1.8.RELEASE
    

    com.zzhua
    demo-user-service
    1.0-SNAPSHOT


    
        
            org.springframework.boot
            spring-boot-starter-web
        
        
            org.springframework.cloud
            spring-cloud-starter-netflix-ribbon
            2.0.1.RELEASE
        
        
    

    
        
            
                org.springframework.boot
                spring-boot-maven-plugin
            
        
    

server:
  port: 8080
order:
  ribbon:
    listOfServers: http://127.0.0.1:8081/,http://127.0.0.1:8082/

package com.zzhua;

import com.netflix.client.config.IClientConfig;
import com.netflix.loadbalancer.*;
import com.zzhua.rule.FirstRule;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;

import java.util.List;

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

package com.zzhua.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
import org.springframework.context.annotation.Bean;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@RestController
public class UserController {

    @Autowired
    private LoadBalancerClient loadBalancerClient;

    @Autowired
    private RestTemplate restTemplate;

    @RequestMapping("user")
    public Object user() {
        ServiceInstance si = loadBalancerClient.choose("order");
        String result = new RestTemplate().getForObject(String.format("http://%s:%s/order", si.getHost(), si.getPort()), String.class);
        return result;
    }

    @RequestMapping("user2")
    public Object user2() {
        String result = restTemplate.getForObject("http://order/order", String.class);
        return result;
    }

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

    4.0.0

    
        org.springframework.boot
        spring-boot-starter-parent
        2.1.8.RELEASE
    

    com.zzhua
    demo-order-service
    1.0-SNAPSHOT

    
        
            org.springframework.boot
            spring-boot-starter-web
        
    

    
        
            
                org.springframework.boot
                spring-boot-maven-plugin
            
        
    

package com.zzhua;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

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

package com.zzhua.controller;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class OrderController {

    @Value("${server.port}")
    private int port;

    @RequestMapping("order")
    public Object order() {
        return "order: " + port;
    }
}

访问：localhost:8080/user & localhost:8080/user2 都可以看到负载均衡的效果