springboot动态修改配置文件

Posted 2021-09-04 岁月峥嵘走过

由于时间关系，仅记录要点：
1.引入 spring-boot-starter-actuator及spring-cloud-starter-config
2.对需要刷新的属性使用@Value注解，同时将类使用@RefreshScope注解进行标记

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
        
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-config</artifactId>
            <version>2.1.5.RELEASE</version>
        </dependency>
        
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
    </dependencies>

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

@SpringBootApplication
public class Main {
    public static void main(String[] args) {
        SpringApplication.run(Main.class);
    }

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.cloud.context.refresh.ContextRefresher;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.MapPropertySource;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import java.util.HashMap;

@RestController
@RefreshScope
public class TestController {

    @Autowired
    private ContextRefresher contextRefresher;

    @Autowired
    private ConfigurableEnvironment environment;

    @Value("${user.test1}")
    private String test1;


    @GetMapping("test1")
    public String getInxo1() {

        return this.test1;
    }


    @PostMapping("refresh")
    public String default02(@RequestParam String name){

        HashMap<String,Object> map = new HashMap<>();
        map.put("user.test1",name);
        MapPropertySource propertySource = new MapPropertySource("dynamic",map);
        environment.getPropertySources().addFirst(propertySource);
        new Thread(() -> contextRefresher.refresh()).start();
        return "success";
    }
    
}

3.application.properties配置。（注意2.0.3版本后暴露/refresh接入点的方式与旧版本不同，需要手动设置暴露点。）

server.port=8888
management.endpoints.web.exposure.include=refresh
user.test1="hello world"

4.测试
4.1 启动项目，访问 http://localhost:8888/test1
此时浏览器应显示 hello world
4.2 通过post请求，传参修改test1的内容 http://localhost:8888/refresh
4.3 http://localhost:8888/test1