Spring Cloud LoadBalancer的使用

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>vnacos</artifactId>
        <groupId>com.nacos</groupId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>

    <modelVersion>4.0.0</modelVersion>

    <artifactId>order-loadbalancer</artifactId>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

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

        <!--nacos-服务注册发现-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
            <exclusions>
                <!--将ribbon排除-->
                <exclusion>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
                </exclusion>
            </exclusions>
        </dependency>


        <!--添加loadbalanncer依赖, 添加spring-cloud的依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-loadbalancer</artifactId>
        </dependency>
    </dependencies>

</project>

 

启动类：

 

package com.order;

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

/**
 * @author vans on 2022/2/16 18:32
 */

/**
 * 此配 scanBasePackages={"com.netflix.client.config.IClientConfig"} 解决：
 *  Consider defining a bean of type 'com.netflix.client.config.IClientConfig' in your configuration.
 */

@SpringBootApplication(scanBasePackages={"com.netflix.client.config.IClientConfig","com.order"})
public class VnOrderApplication {


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

    /**
     *
     * @param restTemplateBuilder
     * @return
     *
     * @LoadBalanced  定义负载均衡器
     *
     */
    @Bean
    @LoadBalanced
    public RestTemplate getRestTemplate(RestTemplateBuilder restTemplateBuilder){
        RestTemplate restTemplate = restTemplateBuilder.build();
        return restTemplate;
    }

}

 

Controller类：

package com.order.controller;

import io.swagger.annotations.ApiImplicitParam;
import io.swagger.annotations.ApiOperation;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.client.RestTemplate;

/**
 * @author vans on 2022/2/16 18:13
 */

@RestController
@RequestMapping("/vn/order")
@Slf4j
public class OrderController {


    @Autowired
    private RestTemplate restTemplate;


    @ApiOperation(value = "获取所有用户列表", notes = "不需要任何参数")
    @ApiImplicitParam(name = "运单号", value = "mailNo", required = false, dataType = "String")
    @RequestMapping(value="/{mailNo}",method = RequestMethod.GET)
    public String getOrder(@PathVariable("mailNo") String mailNo) {

        String message = restTemplate.getForObject("http://stock-service:90/vn/stock", String.class);

        return message;
    }


}