springcloudDemo入门

一、注册、配置中心

​ 1.nacos是阿里巴巴研发的一个集注册中心与配置中心于一体的管理平台，使用其他非常的简单。下载地址为：

https://github.com/alibaba/nacos/releases

​ 2.其中默认的登录名和密码是：nacos/nacos

二、 服务提供方

1.创建maven父工程 springcloud-alibaba-microservice-manager ，修改 pom.xml 文件，添加如下代码：

<packaging>pompackaging>

<parent>
    <groupId>org.springframework.bootgroupId>
    <artifactId>spring-boot-starter-parentartifactId>
    <version>2.2.9.RELEASEversion>
    <relativePath/> 
parent>

2.创建子工程 springcloud-alibaba-microserivce-commons ，创建 User 类

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {

    private Integer uid;
    private String username;

}

3.创建子工程 springcloud-alibaba-microservice-provider-7070 ，修改 pom.xml 文件，添加如下代码：

<?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>springcloud-alibaba-microservice-manager</artifactId>
        <groupId>com.qf</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>springcloud-alibaba-microservice-provider-7070</artifactId>

    <dependencies>

        <dependency>
            <groupId>com.wei</groupId>
            <artifactId>springcloud-alibaba-microserivce-commons</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>

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

        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>2.2.1.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Hoxton.SR6</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

</project>

3.在 resources 目录下创建 application.yml

spring:
  application:
    # 服务提供方的名称
    name: microservice-provider

  cloud:
    nacos:
      discovery:
        enabled: true
        server-addr: 127.0.0.1:8848

server:
  port: 7070

4.在子工程 springcloud-alibaba-microservice-provider-7070中，创建 MicroServiceProvider 类

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

@SpringBootApplication
@EnableDiscoveryClient
public class MicroServiceProvider {

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

5.创建 UserController

import com.qf.pojo.User;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.Arrays;
import java.util.List;

@RestController
@RequestMapping("provider-user")
public class UserController {

    @RequestMapping("findAll")
    public List findAll(){

        return Arrays.asList(new User(1001,"jack"),new User(1002,"tom"));
    }
}

三. 服务消费方

1.创建子工程 springcloud-alibaba-microservice-consumer-8080，修改 pom.xml 文件，添加如下代码：

<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>springcloud-alibaba-microservice-managerartifactId>
        <groupId>com.qfgroupId>
        <version>1.0-SNAPSHOTversion>
    parent>
    <modelVersion>4.0.0modelVersion>

    <artifactId>springcloud-alibaba-microservice-consumer-8080artifactId>


    <dependencies>

        <dependency>
            <groupId>com.weigroupId>
            <artifactId>springcloud-alibaba-microserivce-commonsartifactId>
            <version>1.0-SNAPSHOTversion>
        dependency>

        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-webartifactId>
        dependency>

        <dependency>
            <groupId>com.alibaba.cloudgroupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discoveryartifactId>
        dependency>
    dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.alibaba.cloudgroupId>
                <artifactId>spring-cloud-alibaba-dependenciesartifactId>
                <version>2.2.1.RELEASEversion>
                <type>pomtype>
                <scope>importscope>
            dependency>
            <dependency>
                <groupId>org.springframework.cloudgroupId>
                <artifactId>spring-cloud-dependenciesartifactId>
                <version>Hoxton.SR6version>
                <type>pomtype>
                <scope>importscope>
            dependency>
        dependencies>
    dependencyManagement>

project>

2.在 resources 目录下创建 application.yml

spring:
  application:
    # 服务消费方的名称
    name: microservice-consumer

  cloud:
    nacos:
      discovery:
        enabled: true
        server-addr: 127.0.0.1:8848

server:
  port: 8080

4.在子工程 springcloud-alibaba-microservice-consumer-8080中，创建 MicroServiceConsumer类

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

@SpringBootApplication
public class MicroServiceConsumer {

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

5.创建 WebConfig

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

@Configuration
public class WebConfig {

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

6.创建 UserController

import com.qf.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import java.util.List;

@RestController
@RequestMapping("consumer-user")
public class UserController {

    @Autowired
    private DiscoveryClient discoveryClient;

    @Autowired
    private RestTemplate restTemplate;//用于发送网络请求

    @RequestMapping("getUsers")
    public List<User> getUsers(){
        //通过服务提供方的名称拿到服务，由于服务提供方可能是集群，所以使用List封装：每一个服务封装成一个ServiceInstance
        List<ServiceInstance> serviceInstances = discoveryClient.getInstances("microservice-provider");
        ServiceInstance serviceInstance = serviceInstances.get(0);//获取服务
        String host = serviceInstance.getHost();//获取主机名
        int port = serviceInstance.getPort();//获取端口号
        String url = "http://"+host+":"+port+"/provider-user/findAll";

        List<User> users = (List<User>)restTemplate.getForObject(url, List.class);

        return users;
    }
}

分别启动服务方以及消费方，然后访问：http://localhost:8080/consumer-user/getUsers 进行测试

也可在nacos上查看注册的服务。