SpringBoot整合Nacos

文章目录

Nacos安装启动

一键傻瓜试安装即可，官网写的很清楚这里不在赘述。这里以Window环境安装为例。

启动

Nacos

将模式改为单机模式。

启动成功

Nacos相关配置

demo-dev.yaml

server:port:8001config:info:"config info for dev from nacos config center"

demo-test.yaml

server:port:3333config:info:"config info for test from nacos config center"

user.yaml

user:name: zs1112222
  age:10address: 测试地址

整合Nacos代码

整合Nacos配置中心，注册中心，完整项目地址 gitee地址。

引入pom.xml依赖

<parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.2.2.RELEASE</version></parent><dependencies><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId><version>2.2.2.RELEASE</version></dependency><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId><version>2.2.2.RELEASE</version></dependency></dependencies>

bootstrap.yml

spring:profiles:# 指定环境 切换环境active: dev
  application:name: demo
  cloud:# nacos server dataId# ${spring.application.name)}-${spring.profiles.active}.${spring.cloud.nacos.config.file-extension}nacos:# Nacos服务注册中心discovery:serverAddr: @serverAddr@
        group: DEMO_GROUP
        namespace: 25af15f3-ae79-41c3-847d-960adb953185
        username: @username@
        password: @password@
      # Nacos作为配置中心config:server-addr: @serverAddr@
        file-extension: yaml
        group: DEMO_GROUP
        namespace: 25af15f3-ae79-41c3-847d-960adb953185
        username: @username@
        password: @password@
        # 加载多配置extension-configs:-data-id: user.yaml
            group: DEMO_GROUP
            refresh:true

UserConfig

@Data@Configuration@ConfigurationProperties(prefix ="user")publicclassUserConfig{privateString name;privateInteger age;privateString address;}

BeanAutoRefreshConfigExample

@RestControllerpublicclassBeanAutoRefreshConfigExample{@AutowiredprivateUserConfig userConfig;@GetMapping("/user/hello")publicStringhello(){return userConfig.getName()+ userConfig.getAge()+ userConfig.getAddress();}}

ValueAnnotationExample

@RestController@RefreshScopepublicclassValueAnnotationExample{@Value("${config.info}")privateString configInfo;@GetMapping("/config/info")publicStringgetConfigInfo(){return configInfo;}}

DemoApplication

@SpringBootApplicationpublicclassDemoApplication{publicstaticvoidmain(String[] args){SpringApplication.run(DemoApplication.class, args);}}

测试结果

补充-刷新静态配置

有时候一些老项目或者一些写法会遇到静态的配置，这时候可以利用Java的反射特性来刷新静态变量。大致原理为，通过监听

Nacos

配置改动确定改动的配置，进而缩小更新范围，通过反射更新变量。

<!-- https://mvnrepository.com/artifact/com.purgeteam/dynamic-config-spring-boot-starter --><dependency><groupId>com.purgeteam</groupId><artifactId>dynamic-config-spring-boot-starter</artifactId><version>0.1.1.RELEASE</version></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></dependency>

NacosRefreshStaticField

@Target({ElementType.TYPE})@Retention(RetentionPolicy.RUNTIME)@Documentedpublic@interfaceNacosRefreshStaticField{StringconfigPrefix()default"";}

NacosListener

@Slf4j@Component@EnableDynamicConfigEventpublicclassNacosListenerimplementsApplicationListener<ActionConfigEvent>{@AutowiredprivateApplicationContext applicationContext;@SneakyThrows@OverridepublicvoidonApplicationEvent(ActionConfigEvent environment){Map<String,HashMap> map = environment.getPropertyMap();for(Map.Entry<String,HashMap> entry : map.entrySet()){String key = entry.getKey();Map changeMap = entry.getValue();String before =String.valueOf(changeMap.get("before"));String after =String.valueOf(changeMap.get("after"));
            log.info("配置[key:{}]被改变，改变前before：{}，改变后after：{}",key,before,after);String[] configNameArr = key.split("\\.");String configPrefix = configNameArr[0];String configRealVal = configNameArr[configNameArr.length-1];AtomicReference<Class<?>> curClazz =newAtomicReference<>();Map<String,Object> refreshStaticFieldBeanMap = applicationContext.getBeansWithAnnotation(NacosRefreshStaticField.class);for(Map.Entry<String,Object> mapEntry : refreshStaticFieldBeanMap.entrySet()){String beanName = mapEntry.getKey();if(ObjectUtil.isEmpty(beanName)){continue;}String fullClassName = refreshStaticFieldBeanMap.get(beanName).toString().split("@")[0];Class<?> refreshStaticFieldClass;try{
                    refreshStaticFieldClass =Class.forName(fullClassName);}catch(ClassNotFoundException e){thrownewClassNotFoundException("监听nacos刷新当前静态类属性,未找到当前类",e);}NacosRefreshStaticField refreshStaticConfig = refreshStaticFieldClass.getAnnotation(NacosRefreshStaticField.class);if(Objects.nonNull(refreshStaticConfig)&& refreshStaticConfig.configPrefix().equalsIgnoreCase(configPrefix)){
                    curClazz.set(refreshStaticFieldClass);}}Class<?> aClass = curClazz.get();if(Objects.isNull(aClass)){return;}// 利用反射动态更新 静态变量Field[] declaredFields = aClass.getDeclaredFields();for(Field declaredField : declaredFields){if(declaredField.getName().equalsIgnoreCase(configRealVal)){
                    log.info("刷新当前配置 更新当前类[{}] 静态属性 [{}]",aClass.getSimpleName(),declaredField.getName());
                    declaredField.setAccessible(true);
                    declaredField.set(null,after);}}}}}

CommonWebConfig

@Data@Component@ConfigurationProperties(prefix ="common")@RefreshScopepublicclassCommonWebConfig{privateString apiUrl;}

ExampleComponent

@Component@NacosRefreshStaticField(configPrefix="common")publicclassExampleComponent{publicstaticString apiUrl =SpringUtil.getBean(CommonWebConfig.class).getApiUrl();}