保姆教程系列二、Nacos实现注册中心

前言：

请各大网友尊重本人原创知识分享，谨记本人博客：南国以南i

上篇我们介绍到  保姆教程系列一、Linux搭建Nacos

注册中心原理

一、环境准备

• Java版本：1.8+   (Linux centos7虚拟机下安装Jdk1.8)
• MySQL服务：5.6.5+   (Linux Centos7 安装MySQL5.7 图文详解)

二、创建项目

2.1 创建项目父工程

IDEA中创建聚合项目nacos作为父工程,其pom.xml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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <!--SpringBoot版本-->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.3.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <groupId>com.example</groupId>
    <artifactId>nacos</artifactId>
    <version>0.0.1</version>
    <name>nacos</name>
    <description>Spring Cloud Nacos</description>

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

    <!--引入子模块-->
    <modules>
        <module>provider</module><!--生产者-->
        <module>consumer</module><!--消费者-->
    </modules>

    <dependencies>
        <!--web依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--测试依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!--nacos配置中心依赖-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
            <version>2.1.1.RELEASE</version>
        </dependency>
        <!--nacos配置中心依赖-->
        <!--<dependency>-->
            <!--<groupId>org.springframework.cloud</groupId>-->
            <!--<artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>-->
            <!--<version>0.2.1.RELEASE</version>-->
        <!--</dependency>-->
        <!--lombok依赖-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <!--注册中心依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
            <version>0.2.2.RELEASE</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Greenwich.SR2</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>

2.2 创建Provider服务生产者

在父工程Nacos下创建springboot子工程provider，其pom.xml文件为：

<?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>
    <!--父工程-->
    <parent>
        <groupId>com.example</groupId>
        <artifactId>nacos</artifactId>
        <version>0.0.1</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <groupId>com.example</groupId>
    <artifactId>provider</artifactId>
    <version>0.0.1</version>
    <name>provider</name>
    <description>Provider Nacos</description>

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

    <dependencies>
        <!--lombok依赖-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

在启动类ProviderApplication.java中增加@EnableDiscoveryClient注解

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

@SpringBootApplication
@EnableDiscoveryClient//开启注册
public class ProviderApplication {

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

}

配置文件application.yml进行如下配置

#生产者配置
server:
  port: 8081

spring:
  application:
    name: nacos-provider #服务名称
  cloud:
    nacos:
      discovery:  #使用注册中心
        server-addr: 192.168.36.135:8848 #Nacos访问地址
        enabled: true

在服务提供方创建一个对外接口

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RequestMapping("/provider")
@RestController
public class IndexController {

    @GetMapping("/hello")
    public String hello() {
        return "我是provider服务生产者";
    }
}

2.3 创建Consumer服务消费者

在父工程Nacos下创建springboot子工程consumer，其pom.xml文件为：

<?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>
    <!--父工程-->
    <parent>
        <groupId>com.example</groupId>
        <artifactId>nacos</artifactId>
        <version>0.0.1</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <groupId>com.example</groupId>
    <artifactId>consumer</artifactId>
    <version>0.0.1</version>
    <name>consumer</name>
    <description>Consumer Nacos</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <!--feign依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <!--hystrix断路器-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

在启动类ConsumerApplication.java中增加注解

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

@SpringBootApplication
@EnableDiscoveryClient //开启注册
@EnableFeignClients //开启Feign服务
public class ConsumerApplication {

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

}

配置文件application.yml进行如下配置

#消费者配置
server:
  port: 8082

spring:
  application:
    name: nacos-consumer
  cloud:
    nacos:
      discovery:  #使用注册中心
        server-addr: 192.168.36.135:8848
        enabled: true

#开启断路器
feign:
 hystrix:
   enabled: true

使用FeginClient进行服务调用,hystrix进行熔断

import com.example.consumer.hystrix.HystrixUtils;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;

@FeignClient(name = "nacos-provider",fallback = HystrixUtils.class)//服务出现异常进行容错
public interface ProviderFeignClient {

    /**
     * .
     * 调用生产者服务
     * @return
     */
    @GetMapping("/provider/hello")
    String hello();
}

HystrixUtils.class容错类

import com.example.consumer.client.ProviderFeignClient;
import org.springframework.stereotype.Component;

@Component
public class HystrixUtils implements ProviderFeignClient {

    /**
     * .
     * 方法重写
     *
     * @return
     */
    @Override
    public String hello() {
        return "断路器容错,服务开小差了，稍等片刻...";
    }
}

service层服务调用

import com.example.consumer.client.ProviderFeignClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class IndexService {

    @Autowired
    private ProviderFeignClient client; //注入

    public String hello() {
        return client.hello(); // 服务调用
    }
}

在controller中调用service的接口,像一般的接口调用一样

import com.example.consumer.service.IndexService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RequestMapping("/consumer")
@RestController
public class IndexController {

    @Autowired
    private IndexService service;

    @GetMapping("/hello")
    public String hello(){
          return service.hello();
    }
}

三、服务调用测试

3.1 项目启动

启动完成后，在服务提供者和消费者的日志中应该可以分别看到如下信息

INFO 18388 --- [           main] o.s.c.a.n.registry.NacosServiceRegistry  : nacos registry, nacos-provider 192.168.22.1:8081 register finished

3.2 登录Nacos控制台

你会发现服务列表中，已经显示了我们刚才创建的两个项目，并可以对其进行简单的监控和管理。

3.3 使用样例项目

打开浏览器输入：http://localhost:8082/consumer/hello

 Nacos服务发现与Eureak服务发现无差异

敬请关注下篇 保姆教程系列三、Nacos Config–服务配置中心

总结：

我是南国以南i记录点滴每天成长一点点，学习是永无止境的！转载请附原文链接！！！

参考链接