Package org.apache.dubbo.registry.client

Class ServiceDiscoveryRegistry

java.lang.Object
org.apache.dubbo.registry.support.AbstractRegistry
org.apache.dubbo.registry.support.FailbackRegistry
org.apache.dubbo.registry.client.ServiceDiscoveryRegistry
All Implemented Interfaces:
Node, Registry, RegistryService
public class ServiceDiscoveryRegistry extends FailbackRegistry
TODO, this bridge implementation is not necessary now, protocol can interact with service discovery directly.

ServiceDiscoveryRegistry is a very special Registry implementation, which is used to bridge the old interface-level service discovery model with the new service discovery model introduced in 3.0 in a compatible manner.

It fully complies with the extension specification of the Registry SPI, but is different from the specific implementation of zookeeper and Nacos, because it does not interact with any real third-party registry, but only with the relevant components of ServiceDiscovery in the process. In short, it bridges the old interface model and the new service discovery model:

- register() aggregates interface level data into MetadataInfo by mainly interacting with MetadataService. - subscribe() triggers the whole subscribe process of the application level service discovery model. - Maps interface to applications depending on ServiceNameMapping. - Starts the new service discovery listener (InstanceListener) and makes NotifierListeners part of the InstanceListener.

  • Constructor Details

    • ServiceDiscoveryRegistry

      public ServiceDiscoveryRegistry(URL registryURL, ApplicationModel applicationModel)

  • Method Details

    • getServiceDiscovery

      public ServiceDiscovery getServiceDiscovery()

    • register

      public final void register(URL url)
      Description copied from interface: RegistryService
      Register data, such as : provider service, consumer address, route rule, override rule and other data.

      Registering is required to support the contract:
      1. When the URL sets the check=false parameter. When the registration fails, the exception is not thrown and retried in the background. Otherwise, the exception will be thrown.
      2. When URL sets the dynamic=false parameter, it needs to be stored persistently, otherwise, it should be deleted automatically when the registrant has an abnormal exit.
      3. When the URL sets category=routers, it means classified storage, the default category is providers, and the data can be notified by the classified section.
      4. When the registry is restarted, network jitter, data can not be lost, including automatically deleting data from the broken line.
      5. Allow URLs which have the same URL but different parameters to coexist,they can't cover each other.

      Specified by:
      register in interface RegistryService
      Overrides:
      register in class FailbackRegistry
      Parameters:
      url - Registration information , is not allowed to be empty, e.g: dubbo://10.20.153.10/org.apache.dubbo.foo.BarService?version=1.0.0invalid input: '&application'=kylin

    • doRegister

      public void doRegister(URL url)
      Specified by:
      doRegister in class FailbackRegistry

    • unregister

      public final void unregister(URL url)
      Description copied from interface: RegistryService
      Unregister

      Unregistering is required to support the contract:
      1. If it is the persistent stored data of dynamic=false, the registration data can not be found, then the IllegalStateException is thrown, otherwise it is ignored.
      2. Unregister according to the full url match.

      Specified by:
      unregister in interface RegistryService
      Overrides:
      unregister in class FailbackRegistry
      Parameters:
      url - Registration information , is not allowed to be empty, e.g: dubbo://10.20.153.10/org.apache.dubbo.foo.BarService?version=1.0.0invalid input: '&application'=kylin

    • doUnregister

      public void doUnregister(URL url)
      Specified by:
      doUnregister in class FailbackRegistry

    • subscribe

      public final void subscribe(URL url, NotifyListener listener)
      Description copied from interface: RegistryService
      Subscribe to eligible registered data and automatically push when the registered data is changed.

      Subscribing need to support contracts:
      1. When the URL sets the check=false parameter. When the registration fails, the exception is not thrown and retried in the background.
      2. When URL sets category=routers, it only notifies the specified classification data. Multiple classifications are separated by commas, and allows asterisk to match, which indicates that all categorical data are subscribed.
      3. Allow interface, group, version, and classifier as a conditional query, e.g.: interface=org.apache.dubbo.foo.BarServiceinvalid input: '&version'=1.0.0
      4. And the query conditions allow the asterisk to be matched, subscribe to all versions of all the packets of all interfaces, e.g. :interface=*invalid input: '&group'=*invalid input: '&version'=*invalid input: '&classifier'=*
      5. When the registry is restarted and network jitter, it is necessary to automatically restore the subscription request.
      6. Allow URLs which have the same URL but different parameters to coexist,they can't cover each other.
      7. The subscription process must be blocked, when the first notice is finished and then returned.

      Specified by:
      subscribe in interface RegistryService
      Overrides:
      subscribe in class FailbackRegistry
      Parameters:
      url - Subscription condition, not allowed to be empty, e.g. consumer://10.20.153.10/org.apache.dubbo.foo.BarService?version=1.0.0invalid input: '&application'=kylin
      listener - A listener of the change event, not allowed to be empty

    • doSubscribe

      public void doSubscribe(URL url, NotifyListener listener)
      Specified by:
      doSubscribe in class FailbackRegistry

    • unsubscribe

      public final void unsubscribe(URL url, NotifyListener listener)
      Description copied from interface: RegistryService
      Unsubscribe

      Unsubscribing is required to support the contract:
      1. If you don't subscribe, ignore it directly.
      2. Unsubscribe by full URL match.

      Specified by:
      unsubscribe in interface RegistryService
      Overrides:
      unsubscribe in class FailbackRegistry
      Parameters:
      url - Subscription condition, not allowed to be empty, e.g. consumer://10.20.153.10/org.apache.dubbo.foo.BarService?version=1.0.0invalid input: '&application'=kylin
      listener - A listener of the change event, not allowed to be empty

    • doUnsubscribe

      public void doUnsubscribe(URL url, NotifyListener listener)
      Specified by:
      doUnsubscribe in class FailbackRegistry

    • lookup

      public List<URL> lookup(URL url)
      Description copied from interface: RegistryService
      Query the registered data that matches the conditions. Corresponding to the push mode of the subscription, this is the pull mode and returns only one result.
      Specified by:
      lookup in interface RegistryService
      Overrides:
      lookup in class AbstractRegistry
      Parameters:
      url - Query condition, is not allowed to be empty, e.g. consumer://10.20.153.10/org.apache.dubbo.foo.BarService?version=1.0.0invalid input: '&application'=kylin
      Returns:
      The registered information list, which may be empty, the meaning is the same as the parameters of NotifyListener.notify(List<URL>).
      See Also:

    • isAvailable

      public boolean isAvailable()

    • destroy

      public void destroy()
      Specified by:
      destroy in interface Node
      Overrides:
      destroy in class FailbackRegistry

    • isServiceDiscovery

      public boolean isServiceDiscovery()

    • supports

      public static boolean supports(URL registryURL)
      Supports or not ?
      Parameters:
      registryURL - the url of registry
      Returns:
      if supported, return true, or false

    • getServiceListeners

      public Map<String,ServiceInstancesChangedListener> getServiceListeners()

    • getAppSubscription

      public Lock getAppSubscription(String key)

    • removeAppSubscriptionLock

      public void removeAppSubscriptionLock(String key)