SpingCloud 2020微服务教程【46】Nacos模块搭建_springcloud 增加nacosmodule-优快云博客

本文链接：https://blog.youkuaiyun.com/REX1129/article/details/112557026

视频链接：2020最新版SpringCloud框架开发教程-周阳
文章源码：https://github.com/geyiwei-suzhou/cloud2020/

服务提供者

cloudalibaba-provider-payment9001模块

1. 建module

New --> Module --> Maven[Module SDK:1.8.0_191] --> name[cloudalibaba-provider-payment9001] --> Finish

2. 改pom

<?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>cloud2020</artifactId>
    <groupId>com.antherd.springcloud</groupId>
    <version>1.0-SNAPSHOT</version>
  </parent>
  <modelVersion>4.0.0</modelVersion>

  <artifactId>cloudalibaba-provider-payment9001</artifactId>

  <dependencies>
    <!-- Spring Cloud alibaba Nacos -->
    <dependency>
      <groupId>com.alibaba.cloud</groupId>
      <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    </dependency>
    <!--引入公共api包-->
    <dependency>
      <groupId>com.antherd.springcloud</groupId>
      <artifactId>cloud-api-commons</artifactId>
      <version>${project.version}</version>
    </dependency>
    <!-- boot web actuator-->
    <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>
    <!-- 一般通用配置-->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-devtools</artifactId>
      <scope>runtime</scope>
      <optional>true</optional>
    </dependency>
    <dependency>
      <groupId>org.projectlombok</groupId>
      <artifactId>lombok</artifactId>
      <optional>true</optional>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
      <scope>test</scope>
    </dependency>
  </dependencies>
</project>

3. 写yml

server:
  port: 9001

spring:
  application:
    name: nacos-payment-provider
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848 # 配置Nacos地址

management:
  endpoints:
    web:
      exposure:
        include: '*'

4. 主启动

新建类：com.antherd.springcloud.PaymentMain9001

package com.antherd.springcloud;

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

@SpringBootApplication
@EnableDiscoveryClient
public class PaymentMain9001 {

  public static void main(String[] args) {

    SpringApplication.run(PaymentMain9001.class, args);
  }
}

5 写业务

新建类：com.antherd.springcloud.service.IMessageProvider

package com.antherd.springcloud.service;

public interface IMessageProvider {

  public String send();
}

新建类：com.antherd.springcloud.controller.PaymentController

package com.antherd.springcloud.controller;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class PaymentController {

  @Value("${server.port}")
  private String serverPort;

  @GetMapping(value = "/payment/nacos/{id}")
  public String getPayment(@PathVariable("id") Integer id) {
    return "nacos registry，serverPort：" + serverPort + "，id：" + id;
  }
}

6. 启动测试

启动：cloudalibaba-provider-payment9001 模块

访问：http://localhost:8848/nacos/ 点击服务列表，可以看到nacos-payment-provider服务

cloudalibaba-provider-payment9011模块

方法一
右击Idea Services中的PaymentMain9001 --> Copy Configuation --> Name[PaymentMain9011 copy of 9001]、VM option[-DServer.port=9011]、JRE[1.8]
方法二
参照cloudalibaba-provider-payment9001模块新建cloudalibaba-provider-payment9002模块

启动：cloudalibaba-provider-payment9001、cloudalibaba-provider-payment9002 两个模块

访问：http://localhost:8848/nacos/ 点击服务列表，可以看到nacos-payment-provider服务实例数为2

服务消费者

cloudalibaba-consumer-nacos-order83模块

1. 建module

New --> Module --> Maven[Module SDK:1.8.0_191] --> name[cloudalibaba-consumer-nacos-order83] --> Finish

2. 改pom

<?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>cloud2020</artifactId>
    <groupId>com.antherd.springcloud</groupId>
    <version>1.0-SNAPSHOT</version>
  </parent>
  <modelVersion>4.0.0</modelVersion>

  <artifactId>cloudalibaba-consumer-nacos-order83</artifactId>

  <dependencies>
    <!-- SpringCloud alibaba nacos -->
    <dependency>
      <groupId>com.alibaba.cloud</groupId>
      <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    </dependency>
    <!--引入公共api包-->
    <dependency>
      <groupId>com.antherd.springcloud</groupId>
      <artifactId>cloud-api-commons</artifactId>
      <version>${project.version}</version>
    </dependency>
    <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-devtools</artifactId>
      <scope>runtime</scope>
      <optional>true</optional>
    </dependency>
    <dependency>
      <groupId>org.projectlombok</groupId>
      <artifactId>lombok</artifactId>
      <optional>true</optional>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
      <scope>test</scope>
    </dependency>
  </dependencies>
</project>

3. 写yml

server:
  port: 83

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

# 消费者将要去访问的微服务名称（注册成功进nacos的微服务提供者）
service-url:
  nocos-user-service: http://nacos-payment-provider

4. 主启动

新建类：com.antherd.springcloud.OrderNacosMain83

package com.antherd.springcloud.alibaba;

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

@SpringBootApplication
@EnableDiscoveryClient
public class OrderNacosMain83 {

  public static void main(String[] args) {

    SpringApplication.run(OrderNacosMain83.class, args);
  }
}

5 写业务

新建类：com.antherd.springcloud.alibaba.config.ApplicationContextConfig

package com.antherd.springcloud.alibaba.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 ApplicationContextConfig {

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

新建类：com.antherd.springcloud.alibaba.controller.OrderNacosController

package com.antherd.springcloud.alibaba.controller;

import javax.annotation.Resource;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
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;

@RestController
@Slf4j
public class OrderNacosController {

  @Resource
  private RestTemplate restTemplate;

  @Value("${service-url.nocos-user-service}")
  private String serverURL;

  @GetMapping(value = "/consumer/payment/nacos/{id}")
  public String paymentInfo(@PathVariable("id") Long id) {
    return restTemplate.getForObject(serverURL + "/payment/nacos/" + id, String.class);
  }
}

6. 启动测试

启动：cloudalibaba-provider-payment9001、cloudalibaba-provider-payment9002、cloudalibaba-consumer-nacos-order83 三个模块

访问：http://localhost:83/consumer/payment/nacos/1 发现nacos自带负载均衡，依次调用cloudalibaba-provider-payment9001、cloudalibaba-provider-payment9002两个模块

Nacos AP/CP 切换

如果不需要存储服务级别的信息且服务实例是通过nacos-client注册，并能够保持心跳上报，那么可以选择AP模式。当前主流的服务如Spring Cloud和Dubbo服务，都适用于AP模式，AP模式为了服务的可能性而减弱了一致性，因此AP模式下只支持注册临时实例
如果需要在服务级别编辑或者存储配置信息，那么CP是必须，K8S服务和DNS服务则适用于CP模式。CP模式下则支持注册持久化，此时则是以Raft协议为集群运行模式，该模式下注册实例之前必须先注册服务，如果服务不存在，则返回错误

Nacos 切换AP/CP使用如下命令：

curl -X PUT '$NACOS_SERVER:8848/nacos/v1/ns/operator/switches?entry=serverMode&value=CP'