02--创建一个工程并将其注册至nacos，并使用nacos配置-蒲公英云

nacos 环境搭建请参考

新建一maven项目spring-cloud-alibaba
删除 spring-cloud-alibaba 项目中的 src文件

pom.xml中引入springboot及springcloudalibab依赖

<?xml version=”1.0” encoding=”UTF-8”?>

<modelVersion>4.0.0</modelVersion>
<groupId>spring-cloud-alibaba</groupId>
<artifactId>spring-cloud-alibaba</artifactId>
<version>1.0-SNAPSHOT</version>
<name>spring-cloud-alibaba</name>
<url>http://www.xxx.xxx</url>
<description>spring-cloud-alibaba</description>
<properties>
    <java.version>1.8</java.version>
    <spring.cloud.version>Greenwich.SR6</spring.cloud.version>
</properties>
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.7.RELEASE</version>
</parent>

    <!-- 依赖声明 -->
    <dependencyManagement>
        <dependencies>
            <!-- SpringCloud 微服务 -->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring.cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!-- SpringCloud Alibaba 微服务 -->
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>2.1.0.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.2</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
    <build>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <filtering>true</filtering>
            </resource>
        </resources>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>8</source>
                    <target>8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

在spring-cloud-alibaba项目中新建producer-example模块
producer-example 模块中引入nacos开发包

<?xml version=”1.0” encoding=”UTF-8”?>

spring-cloud-alibaba
spring-cloud-alibaba
1.0-SNAPSHOT

4.0.0

producer-example

org.springframework.boot
spring-boot-starter-web

com.alibaba.cloud
spring-cloud-starter-alibaba-nacos-discovery

com.alibaba.cloud
spring-cloud-starter-alibaba-nacos-config

org.springframework.boot
spring-boot-maven-plugin

com.cloud.alibaba.ProducerApplication
producer-example模块中 java目录下新建开发目录 com.cloud.alibaba 并新建ProducerApplication启动类

package com.cloud.alibaba;

import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

/* @author 刘志强 @date 2020/11/17 09:29 @EnableDiscoveryClient 启动客户端 */
@EnableDiscoveryClient
@SpringBootApplication
@Slf4j
public class ProducerApplication implements CommandLineRunner {

    public static void main(String[] args) { 
        SpringApplication.run(ProducerApplication.class, args);
    }
    @Override
    public void run(String... args) { 
        log.info("producer已启动");
    }
}

resources 目录下新建 bootstrap.yml 文件。
bootstrap.yml和application.yml的区别。Bootstrap属性的优先级高，因此默认情况下不能被本地配置覆盖。

bootstrap.yml

spring:
application:

name: producer-example

profiles:

active: dev

main:

allow-bean-definition-overriding: true

cloud:

nacos:
  discovery:
    # 服务注册地址
    server-addr: 101.37.152.195:8848
  config:
    server-addr: 101.37.152.195:8848
    # 配置文件格式
    file-extension: yml
    # 共享配置
    shared-dataids: application-${ spring.profiles.active}.${ spring.cloud.nacos.config.file-extension}

服务启动 producer-example 服务会注册进nacos, 并读取nacos配置中的 producer-example-dev.yml,producer-example.yml 以及 application-dev.yml配置信息
nacos配置如下

Data ID: producer-example-dev.yml
Group：DEFAULT_GROUP
配置格式：YAML
配置内容：
author:
```
userName: 刘志强
mailbox: 2425358736@qq.com
```

Data ID: producer-example.yml
Group：DEFAULT_GROUP
配置格式：YAML
配置内容：
server:
  port: 10000
Data ID: application-dev.yml
Group：DEFAULT_GROUP
配置格式：YAML
配置内容：
author:
    weChat: Liu19940528

修改启动类 ProducerApplication，打印配置信息

package com.cloud.alibaba;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.core.env.Environment;

/* @author 刘志强 @date 2020/11/17 09:29 @EnableDiscoveryClient 启动客户端 */
@EnableDiscoveryClient
@SpringBootApplication
@Slf4j
public class ProducerApplication implements CommandLineRunner {
```
@Autowired
private Environment env;
public static void main(String[] args) { 
    SpringApplication.run(ProducerApplication.class, args);
}
@Override
public void run(String... args) { 
    log.info("producer已启动");
    log.info(env.getProperty("author.userName"));
    log.info(env.getProperty("author.mailbox"));
    log.info(env.getProperty("author.weChat"));
}
```
}
启动项目观察启动端口和打印信息是否来自nacos配置
观察nacos服务列表是否已将producer-example 注册
springcloud 默认支持热更新spring.cloud.refresh.enabled=true

@RefreshScope 注解刷新作用域。新增Author类

package com.cloud.alibaba.domain;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.stereotype.Component;

/* @author 刘志强 @date 2020/11/17 13:39 /
@RefreshScope
@Component
public class Author {

@Value("${author.userName}")
private String userName;
@Value("${author.mailbox}")
private String mailbox;
@Value("${author.weChat}")
private String weChat;
@Override
public String toString() { 
    return "Author{" +
            "userName='" + userName + '\'' +
            ", mailbox='" + mailbox + '\'' +
            ", weChat='" + weChat + '\'' +
            '}';
}

}

修改启动类

package com.cloud.alibaba;

import com.cloud.alibaba.domain.Author;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

/* @author 刘志强 @date 2020/11/17 09:29 @EnableDiscoveryClient 启动客户端 */
@EnableDiscoveryClient
@SpringBootApplication
@Slf4j
@RestController
public class ProducerApplication implements CommandLineRunner {
```
@Autowired
private Author author;
public static void main(String[] args) { 
    SpringApplication.run(ProducerApplication.class, args);
}
@Override
public void run(String... args) { 
    log.info("producer已启动");
    log.info(author.toString());
}
@GetMapping("/test")
public String test() { 
    return author.toString();
}
```
}
启动后修改配置在访问test接口观察返回值