源码分析：apollo、nacos 读取配置动态刷新

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apollo—代码
nacos—代码

apollo

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结论（放在上面）：@Value 会刷新，Environment获取也会刷新，@ApolloConfigChangeListener 标记方法来监听ConfigChangeEvent事件
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启动：

# 手动 @EnableApolloConfig
# 自动 apollo-client-1.1.0.jar / META-INF / spring.factories / ApolloAutoConfiguration
        -> 注册 @Bean  ConfigPropertySourcesProcessor
                ->      postProcessBeanDefinitionRegistry (方法)   
                        -> SpringValueProcessor       @Value更新-属性
                        -> ApolloAnnotationProcessor  @ApolloConfigChangeListener触发-方法
                ->      postProcessBeanFactory (方法-继承于父类   extends PropertySourcesProcessor)
                        -> initializePropertySources   (添加 ApolloPropertySources)
                        -> initializeAutoUpdatePropertiesFeature   (添加广播 AutoUpdateConfigChangeListener   @Value更新-属性)
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仓库工厂类 DefaultConfigFactory
依赖关系 1.RemoteConfigRepository -> 2.LocalFileConfigRepository -> 3.DefaultConfig

1. RemoteConfigRepository.onLongPollNotified (长轮询通知)
          -> sync (HTTP GET 获取最新配置)
          -> fireRepositoryChange 下游
2. LocalFileConfigRepository.onRepositoryChange
          -> persistLocalCacheFile (持久化本地文件)
          -> fireRepositoryChange 下游
3. DefaultConfig.onRepositoryChange
          -> updateAndCalcConfigChanges (原子更新 properties)
          -> fireConfigChange(ConfigChangeEvent)
          -> for  m_listeners.onChange
                 => AutoUpdateConfigChangeListener.onChange   @Value更新-属性
                 => ApolloAnnotationProcessor.processMethod   @ApolloConfigChangeListener触发-方法
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nacos

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部分参考：     Spring-Cloud源码：@RefreshScope   ===> https://blog.csdn.net/qq_42187215/article/details/130969120
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apollo 会自动刷新（刷新属性值）
Nacos 不会自动刷新（需加 @RefreshScope，而且调用刷新的值，需要是 方法调用才可以）


@NacosValue 测试失败
抽象类 public protected 都测试成功
Nacos要配合 @RefreshScope 才能刷新（方法调用）

环境变量 -> Spring环境中获取，每次都成功
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spring-cloud-context-3.1.1 / META-INF / spring.factories
RefreshAutoConfiguration
    RefreshScope extends GenericScope
    -> super.setName("refresh");
    -> GenericScope.postProcessBeanFactory   --> beanFactory.registerScope(this.name, this);// "refresh"   RefreshScope
    LegacyContextRefresher       (RefreshScope)   @ConditionalOnBootstrapEnabled   √√√
    ConfigDataContextRefresher   (RefreshScope)   @ConditionalOnBootstrapDisabled  ×××
    RefreshEventListener (LegacyContextRefresher)
    -> refreshEnvironment() 与 refreshAll()

@RefreshScope
===> @Scope("refresh")   ---> 默认 NO --- ScopedProxyMode proxyMode() default ScopedProxyMode.DEFAULT;
===> ScopedProxyMode proxyMode() default ScopedProxyMode.TARGET_CLASS;
ClassPathBeanDefinitionScanner.doScan
---> candidate.setScope(scopeMetadata.getScopeName());
---> AnnotationConfigUtils.applyScopedProxyMode ---> ScopedProxyUtils.createScopedProxy
    -> String targetBeanName = getTargetBeanName(originalBeanName);   --- "scopedTarget." + originalBeanName;// scopedTarget.testController
    -> RootBeanDefinition proxyDefinition = new RootBeanDefinition(ScopedProxyFactoryBean.class);
    -> targetDefinition.setAutowireCandidate(false);// 原始Bean定义 不能被依赖
    -> registry.registerBeanDefinition(targetBeanName, targetDefinition);// 注册 "scopedTarget.testController"，原始Bean定义
    -> return new BeanDefinitionHolder(proxyDefinition, originalBeanName, definition.getAliases());// 注册 "testController"，代理Bean定义
GenericScope.postProcessBeanDefinitionRegistry
---> LockedScopedProxyFactoryBean （实现 FactoryBean---getObject()---proxy === 别人依赖它，都会依赖 proxy 代理对象，每次从容器中获取新的对象）
---> LockedScopedProxyFactoryBean.setBeanFactory ---> ScopedProxyFactoryBean.setBeanFactory
    -> this.scopedTargetSource.setBeanFactory(beanFactory);
    -> pf.setTargetSource(this.scopedTargetSource);// SimpleBeanTargetSource
    -> this.proxy = pf.getProxy(cbf.getBeanClassLoader());// CGLIB 代理对象

CglibAopProxy.DynamicAdvisedInterceptor.intercept
-> TargetSource targetSource = this.advised.getTargetSource();// SimpleBeanTargetSource
-> target = targetSource.getTarget();// SimpleBeanTargetSource.getTarget   ------> getBeanFactory().getBean(getTargetBeanName());
-> retVal = new CglibMethodInvocation(proxy, target, method, args, targetClass, chain, methodProxy).proceed();
        -> LockedScopedProxyFactoryBean.invoke
        -> return ReflectionUtils.invokeMethod(method, advised.getTargetSource().getTarget(), invocation.getArguments());

AbstractBeanFactory.doGetBean   -> scope='refresh'
GenericScope.get
    -> this.cache.put ---> this.cache.putIfAbsent(name, value);
    -> return value.getBean();     --->  if (this.bean == null) { this.bean = this.objectFactory.getObject(); }
AbstractAutowireCapableBeanFactory.doCreateBean
    -> populateBean
    -> postProcessProperties   Autowired处理器填充属性    最终环境变量里面解析占位符

只有发布的时候，才会刷新 this，重新创建
===> Controller拦截器 getBean 会判断缓存，如果有就直接返回，没有才创建
===> 只有 Nacos配置更新，长轮询发送 RefreshEvent，从而 refreshEnvironment()，scope.refreshAll()---destroy()---cache.clear() 清空缓存，下次请求重新创建
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ClientWorker.LongPollingRunnable.run
-> cacheData.checkListenerMd5();
-> listener.receiveConfigInfo(contentTmp);  ---> AbstractSharedListener.receiveConfigInfo
    NacosContextRefresher (NacosConfigAutoConfiguration)
    -> registerNacosListener   configService.addListener
    -> RefreshEvent
    
    RefreshEventListener.onApplicationEvent (RefreshAutoConfiguration)
    -> handle((RefreshEvent) event);
        -> this.refresh.refresh()   (LegacyContextRefresher)
        -> ContextRefresher.refresh
            		Set<String> keys = refreshEnvironment();
		            this.scope.refreshAll();  ---> super.destroy();    GenericScope.destroy()
		                -> this.cache.clear()
		                -> wrapper.destroy();      this.bean = null;

@RefreshScope 修饰的类，调用方法时，会被 CGLIB 代理
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