SpringCloud: polaris服务消费者

一、创建Spring Cloud项目，并加入polaris相关依赖：

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.tencent</groupId>
    <artifactId>polaris2022</artifactId>
    <version>1.0-SNAPSHOT</version>



    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.10</version>
    </parent>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.tencent.cloud</groupId>
                <artifactId>spring-cloud-tencent-dependencies</artifactId>
                <version>1.7.0-2021.0.3</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>2021.0.3</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

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

        <dependency>
            <groupId>com.tencent.cloud</groupId>
            <artifactId>spring-cloud-starter-tencent-polaris-discovery</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-bootstrap</artifactId>
        </dependency>
    </dependencies>

</project>

二、在bootstrap.yml中配置polaris相关地址：

server:
  port: 48084
spring:
  application:
    name: ConsumerExample
  cloud:
    polaris:
      address: grpc://127.0.0.1:8091
      discovery:
        enabled: true

三、配置RestTemplate并加上@LoadBalanced注解：

package cn.edu.tju.config;

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;

@Configuration
public class RestConfig {
    @Bean
    @LoadBalanced
    public RestTemplate getRestTemplate(){
        return new RestTemplate();
    }
}

四、创建控制器类，并注入RestTemplate,通过它来访问注册到polaris中的服务：

package cn.edu.tju.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@RestController
public class TestController {
    @Autowired
    private RestTemplate restTemplate;
    @GetMapping("/hi")
    public String hi(){
        String result = restTemplate.getForObject("http://BootEchoServer/echo/hi",String.class);
        return result;
    }
}

五、创建启动类，并启动程序：

package cn.edu.tju;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;


@SpringBootApplication
public class Start {

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