nacos源码分析==客户端从服务端读取配置文件-服务端服务注册

客户端从服务端读取配置文件

客户端启动的时候会扫描到boostrap.yml中的信息扫描到标签@ConditionalOnProperty会将NacosConfigBootstrapConfiguration 中的bean注入。其中NacosConfigProperties就是读取的boostrap.yml中spring.cloud.nacos.config下的配置项。NacosConfigBootstrapConfiguration创建除了NacosPropertySourceLocator对象并注入容器。

@Configuration(proxyBeanMethods = false)
@ConditionalOnProperty(name = "spring.cloud.nacos.config.enabled", matchIfMissing = true)
public class NacosConfigBootstrapConfiguration {

	@Bean
	@ConditionalOnMissingBean
//扫描bootstrap.yml中的spring.cloud.nacos.config下的配置项
	public NacosConfigProperties nacosConfigProperties() {
		return new NacosConfigProperties();
	}

	@Bean
	@ConditionalOnMissingBean
//得到NacosConfigService
	public NacosConfigManager nacosConfigManager(
			NacosConfigProperties nacosConfigProperties) {
		return new NacosConfigManager(nacosConfigProperties);
	}

	@Bean
//创建处NacosPropertySourceLocator
	public NacosPropertySourceLocator nacosPropertySourceLocator(
			NacosConfigManager nacosConfigManager) {
		return new NacosPropertySourceLocator(nacosConfigManager);
	}

	/**
	 * Compatible with bootstrap way to start.
	 */
	@Bean
	@ConditionalOnMissingBean(search = SearchStrategy.CURRENT)
	@ConditionalOnNonDefaultBehavior
	public ConfigurationPropertiesRebinder smartConfigurationPropertiesRebinder(
			ConfigurationPropertiesBeans beans) {
		// If using default behavior, not use SmartConfigurationPropertiesRebinder.
		// Minimize te possibility of making mistakes.
		return new SmartConfigurationPropertiesRebinder(beans);
	}

}

客户端启动的时候会与服务端建立连接其实是为了去服务端拉取配置文件当然会同时把连接创建了调用栈如下可见会执行到之前注入的NacosPropertySourceLocator中。

start:278, RpcClient (com.alibaba.nacos.common.remote.client)

ensureRpcClient:885, ClientWorker$ConfigRpcTransportClient (com.alibaba.nacos.client.config.impl)

getOneRunningClient:1044, ClientWorker$ConfigRpcTransportClient (com.alibaba.nacos.client.config.impl)

queryConfig:940, ClientWorker$ConfigRpcTransportClient (com.alibaba.nacos.client.config.impl)

getServerConfig:397, ClientWorker (com.alibaba.nacos.client.config.impl)
getConfigInner:166, NacosConfigService (com.alibaba.nacos.client.config)
getConfig:94, NacosConfigService (com.alibaba.nacos.client.config)
loadNacosData:85, NacosPropertySourceBuilder (com.alibaba.cloud.nacos.client)
build:73, NacosPropertySourceBuilder (com.alibaba.cloud.nacos.client)
loadNacosPropertySource:199, NacosPropertySourceLocator (com.alibaba.cloud.nacos.client)
loadNacosDataIfPresent:186, NacosPropertySourceLocator (com.alibaba.cloud.nacos.client)
loadNacosConfiguration:158, NacosPropertySourceLocator (com.alibaba.cloud.nacos.client)
loadSharedConfiguration:116, NacosPropertySourceLocator (com.alibaba.cloud.nacos.client)
locate:101, NacosPropertySourceLocator (com.alibaba.cloud.nacos.client)
locateCollection:51, PropertySourceLocator (org.springframework.cloud.bootstrap.config)
locateCollection:47, PropertySourceLocator (org.springframework.cloud.bootstrap.config)

initialize:95, PropertySourceBootstrapConfiguration (org.springframework.cloud.bootstrap.config)

applyInitializers:604, SpringApplication (org.springframework.boot)

prepareContext:373, SpringApplication (org.springframework.boot)
run:306, SpringApplication (org.springframework.boot)
run:1303, SpringApplication (org.springframework.boot)
run:1292, SpringApplication (org.springframework.boot)
main:22, RuoYiSystemApplication (com.ruoyi.system)

起始点是PropertySourceBootstrapConfiguration 这个类是由could-context注入容器

又因为PropertySourceBootstrapConfiguration实现了ApplicationContextInitializer接口所以会在springboot启动过程(refresh方法前)被调用到prepareContext-applyInitializers它的initialize方法会根据bootstarp.yml中指定的dev去加载对应的配置文件。initialize方法会调用之前已经注入的NacosPropertySourceLocator

 com.alibaba.cloud.nacos.client.NacosPropertySourceLocator#locate

该方法会一次加载三个配置文件

loadSharedConfiguration(composite);第一配置文件application-dev.yml 
loadExtConfiguration(composite);这里没配置就没有
loadApplicationConfiguration(composite, dataIdPrefix, nacosConfigProperties, env);第三配置文件ruoyi-system-dev.yml

加载的方法都差不多发起请求去server端获取

com.alibaba.cloud.nacos.client.NacosPropertySourceBuilder#loadNacosData

com.alibaba.nacos.client.config.NacosConfigService#getConfigInner

com.alibaba.nacos.client.config.impl.ClientWorker#getServerConfig

com.alibaba.nacos.client.config.impl.ClientWorker.ConfigRpcTransportClient#queryConfig

queryConfig方法中会创建RpcClient并调用start方法创建与服务端的连接已有就拿来用。

com.alibaba.nacos.client.config.impl.ClientWorker.ConfigRpcTransportClient#ensureRpcClient

                RpcClient rpcClient = RpcClientFactory
                        .createClient(uuid + "_config-" + taskId, getConnectionType(), newLabels);
                if (rpcClient.isWaitInitiated()) {
                    initRpcClientHandler(rpcClient);
                    rpcClient.setTenant(getTenant());
                    rpcClient.clientAbilities(initAbilities());
                    rpcClient.start();
                }

com.alibaba.nacos.common.remote.client.RpcClient#start

在start方法中创建了一个线程池提交了两个死循环的任务。

queryConfig方法中去请求服务端拿取配置文件

ConfigQueryResponse response = (ConfigQueryResponse) requestProxy(rpcClient, request, readTimeouts);

com.alibaba.nacos.common.remote.client.grpc.GrpcConnection#request该方法会在请求body中加入一个type字段实际就是request的类名获取配置文件的话就是ConfigQueryRequest。

读取到配置文件之后将配置项设置到环境变量中其他组件就能读取到了

com.alibaba.cloud.nacos.client.NacosPropertySourceLocator#addFirstPropertySource

org.springframework.core.env.CompositePropertySource#addFirstPropertySource

来自客户端的请求访问到服务端的handler为

com.alibaba.nacos.config.server.remote.ConfigQueryRequestHandler#handle

这个方法的由来为nacos服务端启动时注入了GrpcSdkServer它实现了BaseRpcServerBaseRpcServer中有个@PostConstruct标注的start方法

com.alibaba.nacos.core.remote.BaseRpcServer#start

com.alibaba.nacos.core.remote.grpc.BaseGrpcServer#startServer

    
    @Override
    public void startServer() throws Exception {
        final MutableHandlerRegistry handlerRegistry = new MutableHandlerRegistry();
        //指定处理请求的handler
        addServices(handlerRegistry, new GrpcConnectionInterceptor());
        
        server = ServerBuilder.forPort(getServicePort()).executor(getRpcExecutor())
                .maxInboundMessageSize(getMaxInboundMessageSize()).fallbackHandlerRegistry(handlerRegistry)
                .compressorRegistry(CompressorRegistry.getDefaultInstance())
                .decompressorRegistry(DecompressorRegistry.getDefaultInstance())
                .addTransportFilter(new AddressTransportFilter(connectionManager))
                .keepAliveTime(getKeepAliveTime(), TimeUnit.MILLISECONDS)
                .keepAliveTimeout(getKeepAliveTimeout(), TimeUnit.MILLISECONDS)
                .permitKeepAliveTime(getPermitKeepAliveTime(), TimeUnit.MILLISECONDS)
                .build();
        
        server.start();
    }

会创建一个io.grpc的Server这个是个抽象接口实现类为ServerImplServerImpl中有个InternalServerInternalServer因为引入了netty所以实现类为NettyServer 。并且调用addServices方法指定处理请求的acceptor为GrpcRequestAcceptor

com.alibaba.nacos.core.remote.grpc.BaseGrpcServer#addServices

 com.alibaba.nacos.core.remote.grpc.GrpcRequestAcceptor#request

然后根据请求参数中带的type=ConfigQueryRequest从服务端的持有的registryHandlers

Map<String, RequestHandler> registryHandlers = new HashMap<>();

中选出本次要用的ConfigQueryRequestHandler。

com.alibaba.nacos.core.remote.RequestHandler#handleRequest

com.alibaba.nacos.config.server.remote.ConfigQueryRequestHandler#handle

com.alibaba.nacos.config.server.remote.ConfigQueryRequestHandler#getContext

看来是提前将配置文件缓存到了服务端本地而没有放在数据库里。

 

=======================================================

断点设置

从上可以看到从客户端发到服务端的消息肯定要经过客户端的com.alibaba.nacos.common.remote.client.grpc.GrpcUtils#convert(com.alibaba.nacos.api.remote.request.Request)

所以只要在这打个断点就知道发往服务端的是什么根据type参数也知道同时服务端应该用哪个handler来处理。 后面发现服务注册竟然没走这个接口,她在自己的方法里new了个请求对象估计不是同一个人写的该统一转换吧。。。

到达服务端的请求肯定要经过服务端的com/alibaba/nacos/core/remote/grpc/GrpcRequestAcceptor.java:96

服务注册走了这

从这能看到服务端谁来处理。大概都是type+Handler。

=================

服务端服务注册

客户端发送注册请求

com.alibaba.nacos.client.naming.remote.gprc.NamingGrpcClientProxy#requestToServer

 

服务端收到注册请求

com.alibaba.nacos.naming.remote.rpc.handler.InstanceRequestHandler#handle

发现报错了

 

 原因是我之前将这个微服务设置成了非临时实例而现在我将它设置成了临时实例因为临时实例才是走GRPC注册否者是走InstancController去了,而我想看下GRPC。解决方法是停掉NACOS将存在本地的METAdata删掉,我这是

"D:\prj_idea\Nacos\distribution\data\protocol\raft\

重启后解决。

 

IP和端口都被服务端拿到了然后发布两个事件ClientRegisterServiceEvent  和InstanceMetadataEvent。事件发布后告知客户端注册成功剩下的事件在服务端异步处理。

 

    @Override
    public void registerInstance(Service service, Instance instance, String clientId) throws NacosException {
//检查合法性之前报错就从这出的
        NamingUtils.checkInstanceIsLegal(instance);
    
        Service singleton = ServiceManager.getInstance().getSingleton(service);
        if (!singleton.isEphemeral()) {
            throw new NacosRuntimeException(NacosException.INVALID_PARAM,
                    String.format("Current service %s is persistent service, can't register ephemeral instance.",
                            singleton.getGroupedServiceName()));
        }
//更改该客户端对应的client对象
        Client client = clientManager.getClient(clientId);
        if (!clientIsLegal(client, clientId)) {
            return;
        }
        InstancePublishInfo instanceInfo = getPublishInfo(instance);
        client.addServiceInstance(singleton, instanceInfo);
        client.setLastUpdatedTime();
        client.recalculateRevision();
//通知我注册完成了
        NotifyCenter.publishEvent(new ClientOperationEvent.ClientRegisterServiceEvent(singleton, clientId));
//通知我的元信息可能变了
        NotifyCenter
                .publishEvent(new MetadataEvent.InstanceMetadataEvent(singleton, instanceInfo.getMetadataId(), false));
    }

上面那两个事件在哪被处理

第一个ClientRegisterServiceEvent

com.alibaba.nacos.naming.core.v2.index.ClientServiceIndexesManager#onEvent

ClientServiceIndexesManager这个类里面两个map估计是把注册上来的客户端的某些信息存在这并且维护起来

存到map中后又发了个事件ServiceChangedEvent这个时间被NamingSubscriberServiceV2Impl监听。可以发现SmartSubscriber 、Subscriber

的实现类都是监听类

com.alibaba.nacos.naming.push.v2.NamingSubscriberServiceV2Impl#onEvent

将发生变化的客户端的最新信息推送给 订阅该客户端的其他客户端

    @Override
    public void onEvent(Event event) {
        if (event instanceof ServiceEvent.ServiceChangedEvent) {
            // If service changed, push to all subscribers.
            ServiceEvent.ServiceChangedEvent serviceChangedEvent = (ServiceEvent.ServiceChangedEvent) event;
            Service service = serviceChangedEvent.getService();
            delayTaskEngine.addTask(service, new PushDelayTask(service, PushConfig.getInstance().getPushTaskDelay()));
            MetricsMonitor.incrementServiceChangeCount(service.getNamespace(), service.getGroup(), service.getName());
        } else if (event instanceof ServiceEvent.ServiceSubscribedEvent) {
            // If service is subscribed by one client, only push this client.
            ServiceEvent.ServiceSubscribedEvent subscribedEvent = (ServiceEvent.ServiceSubscribedEvent) event;
            Service service = subscribedEvent.getService();

//将发生变化的客户端的信息推送给订阅该客户端的其他客户端
            delayTaskEngine.addTask(service, new PushDelayTask(service, PushConfig.getInstance().getPushTaskDelay(),
                    subscribedEvent.getClientId()));
        }
    }