Add Guice module to bind StreamEventPublisher

Add Guice module to setup all necessary bindings for
StreamEventPublisher.

Bug: Issue 14909
Change-Id: I6c04b07b67cea814ff610d8e2be8826f38b76238
2 files changed
tree: 3825971e139d43b3a2611b286eae432a0bb12cc7
  1. src/
  2. .gitignore
  3. BUILD
  4. Jenkinsfile
  5. LICENSE
  6. pom.xml
  7. README.md
README.md

Events Broker API for Gerrit Code Review

API of a generic events broker for use with Gerrit Code Review.

Enables the de-coupling between Gerrit, plugins and the different implementations of a generic events broker.

Stream Events Publisher

It is a quite common use case for consumers of this library to listen for Gerrit events and to stream them on a specific topic.

Since the implementation of such logic is always the same, this library provides a generic stream events publisher which will perform the relevant operations.

In order to listen and stream gerrit events, consumers of this API need to provide a binding for the StreamEventPublisherConfig configuration and java.util.concurrent.Executor binding annotated with StreamEventPublisherExecutor annotation. A default single threaded implementation (StreamEventPublisherExecutor) is provided by the library. The last step is to explicitly bind the Stream Events Publisher, as such:

import com.gerritforge.gerrit.eventbroker.publisher.StreamEventPublisher;
import com.google.gerrit.extensions.registration.DynamicSet;
import com.google.gerrit.server.events.EventListener;
import com.google.inject.AbstractModule;

public class SomeModule extends AbstractModule {
    @Override
    protected void configure() {
        long messagePublishingTimeout = 1000L;

        bind(StreamEventPublisherConfig.class)
                .toInstance(new StreamEventPublisherConfig(
                    "name_of_the_stream_events_topic",
                    messagePublishingTimeout));
        
        bind(Executor.class).annotatedWith(StreamEventPublisherExecutor.class).toProvider(StreamEventPublisherExecutorProvider.class);
        DynamicSet.bind(binder(), EventListener.class).to(StreamEventPublisher.class);
    }
}

Alternative way to setup Stream Event Publisher is to use default Guice module:


import com.gerritforge.gerrit.eventbroker.publisher.StreamEventPublisherModule; import com.google.inject.AbstractModule; import com.google.inject.TypeLiteral; import com.google.inject.name.Names; public class SomeModule extends AbstractModule { @Override protected void configure() { long messagePublishingTimeout = 1000L; bind(StreamEventPublisherConfig.class) .toInstance(new StreamEventPublisherConfig( "name_of_the_stream_events_topic", messagePublishingTimeout)); install(new StreamEventPublisherModule()); } }

Note: To avoid message duplication Stream Events Publisher uses gerrit.instanceId and Event.instanceId to filter out forwarded events.