SpringCloud 使用 nacos配置中心，nacos属性值自动刷新

野性酷女 2021-06-22 15:38 2810阅读 0赞

方式一：yaml中开启 refresh-enabled=true 时（默认开启），通过applicationContext.getEnvironment.getProperty 直接获取

方式二：standalone使用，@NacosValue获取最新值nacos配置信息需要写在配置类上

方式三：结合springcloud ，@Value获取最新值一定要加@RefreshScope注解，配置文件中配置refresh: true

1.原生api

@SpringBootApplication
    public class NacosConfigSimpleApplication {
        public static void main(String[] args) throws InterruptedException {
            ConfigurableApplicationContext applicationContext =
              		SpringApplication.run(NacosConfigSimpleApplication.class, args);
            //取到Spring的配置环境
            while(true){
                ConfigurableEnvironment environment = applicationContext.getEnvironment();
                String username = environment.getProperty("user.name");
                String age = environment.getProperty("user.age");
                System.out.println("username:"+username+" | age:"+age);
                TimeUnit.SECONDS.sleep(1);
            }
        }
    }

2.@NacosValue获取最新值

<dependency>
        <groupId>com.alibaba.boot</groupId>
        <artifactId>nacos-config-spring-boot-starter</artifactId>
        <version>0.2.7</version>
    </dependency>

配置类：

@Configuration
    @EnableNacosConfig(globalProperties = @NacosProperties(serverAddr = "127.0.0.1:8848"))
    @NacosPropertySource(dataId = "example", group="test",autoRefreshed = true)
    public class NacosConfiguration { }

测试类：

@Controller
    public class ConfigController {
        @NacosValue(value = "${test.data}", autoRefreshed = true)
        private boolean data;                                     
    
        @RequestMapping(value = "/test", method = GET)
        @ResponseBody
        public boolean get() { return data; }
    }

3.@Value获取最新值 + @RefreshScope

<dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
        <version>2.2.1.RELEASE</version>
    </dependency>

yaml

spring:
      application:
        name: example
      cloud:
        nacos:
          config:
            extension-configs[0]:
              dataId: test.yml
              group: test
              refresh: true
            server-addr:  127.0.0.1:8848
            namespace: c845e96f-4423-4618-8c26-5e4d510f566a
            enabled: true
            refresh-enabled: true

测试类：

@RestController
    @RefreshScope
    public class TestController {
        @NacosValue(value = "${test.data}", autoRefreshed = true)
        private String data;
        @Value(value = "${test.data}")
        private String datas;
        @GetMapping("test")
        public String test() {
            return "data ：" + data + ",datas="+datas;
        }
    }