小刘学习笔记

创建服务消费者

#概述

服务消费者的创建与服务提供者大同小异，这里采用最原始的一种方式，即显示的使用 LoadBalanceClient 和 RestTemplate 结合的方式来访问。

#POM

创建一个工程名为 hello-spring-cloud-alibaba-consumer 的服务消费者项目，pom.xml 配置如下：

<?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>

    <parent>
        <groupId>ml.yompc</groupId>
        <artifactId>hello-spring-cloud-alibaba</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <relativePath>../pom.xml</relativePath>
    </parent>
    <artifactId>hello-spring-cloud-alibaba-consumer</artifactId>
    <packaging>jar</packaging>

    <name>hello-spring-cloud-alibaba-consumer</name>

    <dependencies>
        <!-- Spring Boot Begin -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>

        <!-- Spring Boot End -->

        <!-- Spring Cloud Begin -->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        </dependency>
        <!-- Spring Cloud End -->
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <mainClass>ml.yompc.hello.spring.cloud.alibaba.consumer.ConsumerApplication</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

Application

package ml.yompc.hello.spring.cloud.alibaba.consumer;

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

/**
 * @email yom535@outlook.com
 * @author: 有民(yom535)
 * @date: 2019/8/20
 * @time: 20:49
 */
@EnableDiscoveryClient
@SpringBootApplication
public class ConsumerApplication {
    public static void main(String[] args) {
        SpringApplication.run(ConsumerApplication.class,args);
    }
}

Configuration

创建一个名为 NacosConsumerConfiguration 的 Java 配置类，主要作用是为了注入 RestTemplate

package ml.yompc.hello.spring.cloud.alibaba.consumer.configure;

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;

/**
 * @email yom535@outlook.com
 * @author: 有民(yom535)
 * @date: 2019/8/20
 * @time: 20:49
 */
@Configuration
public class ConsumerConfiguretion {

    @Bean
    @LoadBalanced
    public RestTemplate restTemplate(){

        return new RestTemplate();
    }

}

Controller

创建一个名为 ConsumerController 测试用的 Controller

package ml.yompc.hello.spring.cloud.alibaba.consumer.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

/**
 * @email yom535@outlook.com
 * @author: 有民(yom535)
 * @date: 2019/8/20
 * @time: 20:49
 */
@RestController
public class ConsumerController {


    private final RestTemplate restTemplate;
    @Autowired
    public ConsumerController(RestTemplate restTemplate) {
        this.restTemplate = restTemplate;
    }

    @GetMapping(value = "/{echo}")
    public String echo(@PathVariable String echo){
        return restTemplate.getForObject("http://hello-spring-cloud-alibaba-provider/"+echo,String.class);
    }
}

配置

application.yml

spring:
  application:
    name: nacos-consumer
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

server:
  port: 9091

management:
  endpoints:
    web:
      exposure:
        include: "*"

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