5.Spring Cloud Alibaba 創(chuàng)建服務消費者

目錄：Spring Cloud Alibaba 系列教程
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概述

服務消費者的創(chuàng)建與服務提供者大同小異枷踏，這里采用最原始的一種方式仇味，即顯示的使用 LoadBalanceClient 和 RestTemplate 結(jié)合的方式來訪問学赛。

POM

創(chuàng)建一個工程名為 hello-spring-cloud-alibaba-nacos-consumer 的服務消費者項目财岔，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>com.wsl</groupId>
        <artifactId>hello-spring-cloud-alibaba-dependencies</artifactId>
        <version>1.0.0-SNAPSHOT</version>
        <relativePath>../hello-spring-cloud-alibaba-dependencies/pom.xml</relativePath>
    </parent>

    <artifactId>hello-spring-cloud-alibaba-consumer</artifactId>
    <packaging>jar</packaging>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <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>
        <!-- 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>com.wsl.consumer.ConsumerApplication</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

Application

package com.wsl.hello.consumer;

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

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

Configuration

創(chuàng)建一個名為 NacosConsumerConfiguration 的 Java 配置類，主要作用是為了注入 RestTemplate

package com.wsl.hello.consumer.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;

@Configuration
public class NacosConsumerConfiguration {

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

Controller

創(chuàng)建一個名為NacosConsumerController測試用的 Controller

package com.wsl.hello.consumer.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@RestController
public class NacosConsumerController {

    @Autowired
    private LoadBalancerClient loadBalancerClient;

    @Autowired
    private RestTemplate restTemplate;

    @Value("${spring.application.name}")
    private String appName;

    @GetMapping(value = "/test/app/name")
    public String test() {
        //使用 LoadBalanceClient 和 RestTemplate 結(jié)合的方式來訪問
        ServiceInstance serviceInstance = loadBalancerClient.choose("nacos-provider");
        String url = String.format("http://%s:%s/test/%s", serviceInstance.getHost(), serviceInstance.getPort(), appName);
        return restTemplate.getForObject(url, String.class);
    }
}

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: "*"

目錄結(jié)構(gòu)

啟動工程

通過瀏覽器訪問 http://localhost:8848/nacos哭懈，即 Nacos Server 網(wǎng)址

你會發(fā)現(xiàn)多了一個名為 nacos-consumer 的服務

這時打開 http://localhost:9091/test/app/name 灾馒，你會在瀏覽器上看到：

Hello Nacos Discovery nacos-consumer

服務的端點檢查

通過瀏覽器訪問 http://localhost:9091/actuator/nacos-discovery 你會在瀏覽器上看到：