Dubbo服务暴露源码分析

暴露服务，通过protocol.export方法完成invoker到exporter的转换dubbo:   DubboProtocol.export(invoker)rmi:  RmiProtocol.export(invoker)injvm:    InjvmProtocol.export(invoker)

AbstractRegistry

client.create().withMode(CreateMode.EPHEMERAL).forPath(path)

new HeaderExchangeServer(server)

createRegistry(url)

register(URL url)

HeaderExchangeServer

RegistryProtocol.OverrideListener

notify(url.getBackupUrls());

exporters.add(exporter)

doRegister(url)

先从缓存中取，没有创建

registedProviderUrl :dubbo://192.168.3.1:20881/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&dubbo=2.0.0&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=16932&side=provider×tamp=1567304294714

loadRegistries(true)

注册中心异步（默认）保存文件C:\\Users\\chaos/.dubbo/dubbo-registry-demo-provider-127.0.0.1:2181.cache

AbstractRegistry

FailbackRegistry

ProtocolFilterWrapper

onApplicationEvent

invoker.getUrl().getServiceKey()

启动服务

synchronizeddoExport()

暴露服务方式：1.serviceBean初始化过程中2.事件通知机制（所有bean初始化完成后）关键： delay

createServer(url)

远程暴露

JavassistProxyFactory

ProxyFactory$Adaptive

Transporter

返回ZookeeperRegistry

listener.notify(categoryList)

protocol.export(invoker)

doExportUrls()

调父类构造器

Protocol$Adaptive

ServiceConfig

final Registry registry = getRegistry(originInvoker)

overrideSubscribeUrl ：provider://192.168.3.1:20881/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&category=configurators&check=false&dubbo=2.0.0&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=16932&side=provider×tamp=1567304294714

子节点变化执行

监听zk的providers，configurators节点变化，通过notify更新url列表合并url:   读取configurators 节点下的数据，两种方案OverrideConfigurator ：  覆盖添加   AbsentConfigurator ：当配置不存在的时候添加 更新exporter

ZookeeperClient

恢复，父类实现

recover()

RegistryProtocol

Protocol

ZookeeperRegistry

openServer(url)

会在com.alibaba.dubbo.demo.DemoService/providers 节点下创建子节点toUrlPath(url) ：/dubbo/com.alibaba.dubbo.demo.DemoService/providers/dubbo%3A%2F%2F192.168.3.1%3A20880%2Fcom.alibaba.dubbo.demo.DemoService%3Fanyhost%3Dtrue%26application%3Ddemo-provider%26dubbo%3D2.0.0%26generic%3Dfalse%26interface%3Dcom.alibaba.dubbo.demo.DemoService%26methods%3DsayHello%26pid%3D20536%26side%3Dprovider%26timestamp%3D1567607129193创建持久节点： /dubbo创建持久节点： /dubbo/com.alibaba.dubbo.demo.DemoService创建持久节点：/dubbo/com.alibaba.dubbo.demo.DemoService/providers创建临时节点： toUrlPath(url)

注册中心协议

createEphemeral(path)

ZookeeperRegistryFactory

DubboNamespaceHandler

doLocalExport(originInvoker)

内部逻辑

getSubscribedOverrideUrl(registedProviderUrl)

获取注册中心 URL

暴露服务到远程

监听zk的节点变化，通过notify更新url列表此处不做处理： getSubscribed().entrySet() 为空

RegistryFactory

创建节点

线程安全

export(invoker)

获得Invoker

serviceKey(url)

CuratorZookeeperClient

ProtocolListenerWrapper

包装业务实现类

URL registryUrl = getRegistryUrl(originInvoker);

provider.xml

path:  /dubbo/com.alibaba.dubbo.demo.DemoService/configurators创建持久节点： path

retryPeriod ： 重试周期 5秒retry();  重试 ， 重新注册和订阅failedRegistered： 缓存了注册失败的url

Spring IOC

模板方法，子类实现

订阅overrideSubscribeUrl

zkClient.addStateListener

RegistryFactory$Adaptive

scope = none，不暴露服务scope != remote，暴露到本地scope != local，暴露到远程默认：服务先暴露到本地，再暴露到远程

registryUrl：zookeeper://127.0.0.1:2181/com.alibaba.dubbo.registry.RegistryService?application=demo-provider&dubbo=2.0.0&export=dubbo%3A%2F%2F192.168.3.1%3A20881%2Fcom.alibaba.dubbo.demo.DemoService%3Fanyhost%3Dtrue%26application%3Ddemo-provider%26bind.ip%3D192.168.3.1%26bind.port%3D20881%26dubbo%3D2.0.0%26generic%3Dfalse%26interface%3Dcom.alibaba.dubbo.demo.DemoService%26methods%3DsayHello%26pid%3D16932%26qos.port%3D22222%26side%3Dprovider%26timestamp%3D1567304294714&pid=16932&qos.port=22222×tamp=1567304294686

AbstractZookeeperClient

DubboExporter

getRegistry(URL url)

组装的url:dubbo://192.168.3.1:20880/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&bind.ip=192.168.3.1&bind.port=20880&dubbo=2.0.0&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=21676&qos.port=22222&side=provider×tamp=1567515993022本地的url: injvm://127.0.0.1/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&bind.ip=192.168.3.1&bind.port=20880&dubbo=2.0.0&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=15756&qos.port=22222&side=provider×tamp=1567517466326registryURL:registry://127.0.0.1:2181/com.alibaba.dubbo.registry.RegistryService?application=demo-provider&dubbo=2.0.0&export=dubbo%3A%2F%2F192.168.3.1%3A20880%2Fcom.alibaba.dubbo.demo.DemoService%3Fanyhost%3Dtrue%26application%3Ddemo-provider%26bind.ip%3D192.168.3.1%26bind.port%3D20880%26dubbo%3D2.0.0%26generic%3Dfalse%26interface%3Dcom.alibaba.dubbo.demo.DemoService%26methods%3DsayHello%26pid%3D11924%26qos.port%3D22222%26side%3Dprovider%26timestamp%3D1567587629400&pid=11924&qos.port=22222®istry=zookeeper×tamp=1567587629383 

protocol.export(invokerDelegete)

启动netty服务

从注册中心订阅overrideSubscribeUrl

解析注册中心配置，获取registryUrls

本地暴露

new DecodeHandler(handler) 

client.create().forPath(path)

doRegister(URL url)

使用了SPI的Adaptive注解，利用javassit生成动态字节码通过代理工厂获取Invoker

getProviderUrl(originInvoker) ：dubbo://192.168.3.1:20880/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&bind.ip=192.168.3.1&bind.port=20880&dubbo=2.0.0&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=19756&qos.port=22222&side=provider×tamp=1567595847730bounds :   map(  providerurl <--> exporter )    避免服务重复暴露 ，先从缓存中去

retry() 

定时器重试机制

Registry

createPersistent(path)

afterPropertiesSet

HeaderExchanger

创建ChildListener，监听子节点变化

AbstractRegistryFactory

ServiceBean

Wrapper.getWrapper(com.alibaba.dubbo.demo.provider.DemoServiceImpl) 

获取订阅url

ProxyFactory

创建监听器

export()

解析并注册

StubProxyFactoryWrapper

通过 ProxyFactory 类的 getInvoker 方法使用 ref 生成一个 AbstractProxyInvoker 实例

new HeaderExchangeHandler(handler)

registryUrls是否有值

连接zookeeper，创建节点，注册服务

服务暴露逻辑执行，先从缓存bounds.get(key)中获取，没有就创建exporter

ExchangeServer

返回server

saveProperties(url)

scope

暴露服务

notify(categoryList)

设置url协议为injvm

暴露服务到本地

返回Invoker

FailbackRegistry

getRegistedProviderUrl(originInvoker)

 loadProperties();        

根据URL获取Registry实现类

InjvmProtocol

缓存exporter

ZookeeperRegistry

exportLocal(url)

url: provider://192.168.3.1:20880/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&category=configurators&check=false&dubbo=2.0.0&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=27480&side=provider×tamp=1567663400836urls.get(0) :empty://192.168.3.1:20880/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&category=configurators&check=false&dubbo=2.0.0&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=27480&side=provider×tamp=1567663400836

NettyServer.doOpen()

获取已注册的服务提供者url