SpringBoot 实现代码修改application.yaml，并动态刷新代码中的配置

1.修改配置文件

• 引入依赖

  # Gradle 配置
  implementation group: 'org.yaml', name: 'snakeyaml', version: '1.23'
  

• 读取application.yaml文件

  TestController.class.getClassLoader().getResource("application.yaml");
  

• 修改文件

  // 读取配置
  String src = EsUserController.class.getClassLoader().getResource("application.yaml").getPath();
  Yaml yaml = new Yaml();
  FileWriter fileWriter;
  FileInputStream fileInputStream = new FileInputStream(new File(src));
  Map<String, Object> yamlMap = yaml.load(fileInputStream);
  Map<String, Object> esMap = (Map<String, Object>) yamlMap.get("elasticsearch");
  // 修改配置
  esMap.put("password", "password");
  // 字符输出
  fileWriter = new FileWriter(new File(src));
  // 用yaml方法把map结构格式化为yaml文件结构
  // 重新写入yaml文件
  fileWriter.write(yaml.dumpAsMap(yamlMap));
  // 刷新
  fileWriter.flush();
  // 关闭流
  fileWriter.close();
  fileInputStream.close();
  

完整代码

public void updateYamlFile() throws IOException {
        String src = EsUserController.class.getClassLoader().getResource("application.yaml").getPath();
        Yaml yaml = new Yaml();
        FileWriter fileWriter;
        FileInputStream fileInputStream = new FileInputStream(new File(src));
        Map<String, Object> yamlMap = yaml.load(fileInputStream);
        Map<String, Object> esMap = (Map<String, Object>) yamlMap.get("elasticsearch");
        esMap.put("password", "password");
        //字符输出
        fileWriter = new FileWriter(new File(src));
        //用yaml方法把map结构格式化为yaml文件结构
        fileWriter.write(yaml.dumpAsMap(yamlMap));
        //刷新
        fileWriter.flush();
        //关闭流
        fileWriter.close();
        fileInputStream.close();
    }

2.动态刷新配置

2.1 创建配置类

@Component
@ConfigurationProperties(prefix="elasticsearch")
public class ESConfig {

    private String host;
    private int port;
    private String user;
    private String password;

		// ... 省略getter() setter()
}

2.2 使用配置类

@RestController
public class EsUserController {

		@Autowired
		private ContextRefresher contextRefresher;		
		@Autowired
		private EsConfig esConfig;

		@GetMapping("/api/refresh")
		public void refresh() {
				// 修改配置文件
				updateYamlFile();
				// 刷新配置文件
				contextRefresher.refresh();
				// 使用刷新后的配置
				System.out.print(esconfig.password)
		}

}

2.3 具体

添加依赖

implementation group: 'org.springframework.cloud', name: 'spring-cloud-context', version: '2.2.6.RELEASE'

借助org.springframework.cloud.context.refresh.ContextRefresher 这个类来实现配置刷新

使用时候直接注入 ContextRefresher, 调用refresh() 方法进行刷新配置

参考文章：

spring boot项目如何通过代码去修改yml里面配置项的值?

SpringBoot 动态加载配置文件及刷新Bean