One 、 Preface

Nacos In addition to being a registry for services , It can also be used as a configuration center for services , Be similar to Spring Cloud Config.
Nacos The configuration center supports hot loading , If necessary Bean Dynamic refresh , Add to class @RefreshScope or @ConfigurationProperties Annotations can be , When Nacos It will be triggered in real time when the server configuration changes org.springframework.cloud.context.refresh.ContextRefresher Of refresh Method , Push the new configuration to the client in real time .

Two 、Nacos Installation

Nacos Refer to this article for the installation of 《Nacos As a registry ( One ) Use Spring Cloud Develop consumer calls to providers 》

3、 ... and 、 Concept

3.1 Profile

Java There are usually multiple projects Profile To configure , Used to differentiate development environments , Test environment , Quasi production environment , Generation environment, etc , One for each environment properties file （ or yml/yaml file ）, And then by setting spring.profiles.active To determine which profile to use .Nacos Config The function of this is to move the contents of these files to a unified configuration center , It is convenient for maintenance and supports dynamic refresh of application after real-time modification .

3.2 Data ID

When using Nacos Config after ,Profile The configuration of is stored in Data ID Next , That is, a Profile Corresponding to one Data ID

Data ID The mosaic format of ：${prefix} - ${spring.profiles.active} . ${file-extension}

prefix The default is spring.application.name Value , You can also configure items through spring.cloud.nacos.config.prefix To configure the

spring.profiles.active take spring.profiles.active Value , That is, the current environment corresponds to profile

file-extension To configure the data format of the content , You can use the configuration item spring.cloud.nacos.config.file-extension To configure the

3.3 Group

Group The default is DEFAULT_GROUP, Can pass spring.cloud.nacos.config.group To configure the , When there are too many configuration items or there are duplicate names , It can be easily managed by grouping

Four 、 Configuration center configuration

4.1 establish 2 individual Data ID

open Nacos Configuration interface , Create... In turn 2 individual Data ID

• nacos-provider-dev.yaml      Configuration of development environment
• nacos-provider-test.yaml      Configuration of test environment

4.1.1 Configuration of development environment

4.1.2 Configuration of test environment  

5、 ... and 、 establish IDEA project

5.1 Create a project

 

 5.2 establish bootstrap.yml

spring:
  application:
    name: nacos-provider
  profiles:
    active: dev
  cloud:
    nacos:
      config:
        server-addr: 192.168.1.17:8848
        prefix: nacos-provider
        group: DEFAULT_GROUP
        file-extension: yaml

  5.3 NacosConfigApplication.java

package com.anron.nacosconfig;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class NacosConfigApplication {

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

}

  5.4 NacosConfigApplication.java

package com.anron.nacosconfig.controller;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 * @Author: Anron
 * @Date: 2020/9/15 17:31
 */
@RestController
@RefreshScope
@RequestMapping("/api")
public class ConfigController {
    Logger log = LoggerFactory.getLogger(this.getClass());

    @Value("${db.host:127.0.0.1}")
    private String dbhost;

    @Value("${db.port:80}")
    private String dbport;

    @RequestMapping("/getConfig")
    public String getConfig() {
        log.info("call db.host = [{}], db.port=[{}]", dbhost, dbport);
        return dbhost + ":" + dbport;
    }
}

6、 ... and 、 test

call URL To test  

http://localhost:8080/api/getConfig

And then modify Nacos Config Configuration data in

Call again URL To test , You can see that the configuration data has been updated

7、 ... and 、 Isolation of configuration

In practical applications , There are several requirements for environmental isolation ：

1、 development environment 、 Test environment 、 The quasi production environment and the production environment need to be isolated

2、 Different projects need to be segregated

3、 Same project , Different modules need to be isolated

Can pass Nacos Server for 、namespace Namespace 、group Group to isolate

• Nacos Server for         spring.cloud.nacos.config.server-addr
• Nacos The namespace of     spring.cloud.nacos.config.namespace, Is namespace ID It's not the name
• Nacos The grouping            spring.cloud.nacos.config.group

stay bootstrap.yml File can be configured by Nacos Of server-addr、namespace and group To distinguish between different configuration information .