/*
* Copyright 2014 Netflix, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.reactivex.netty.pipeline;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelPipeline;
import io.netty.util.concurrent.EventExecutorGroup;
import io.reactivex.netty.channel.ChannelMetricEventProvider;
import io.reactivex.netty.metrics.BytesInspector;
import io.reactivex.netty.metrics.MetricEventsSubject;
import rx.Observable;
/**
* An implementation of {@link PipelineConfigurator} which is ALWAYS added at the end of the pipeline. This
* pipeline configurator bridges between netty's pipeline processing and Rx {@link Observable}
*
* @param <I> Input type for the pipeline. This is the type one writes to this pipeline.
* @param <O> Output type of the emitted observable. This is the type one reads from this pipeline.
*
* @author Nitesh Kant
*/
public abstract class RxRequiredConfigurator<I, O> implements PipelineConfigurator<I, O> {
public static final String CONN_LIFECYCLE_HANDLER_NAME = "conn_lifecycle_handler";
public static final String BYTES_INSPECTOR_HANDLER_NAME = "bytes_inspector";
public static final String NETTY_OBSERVABLE_ADAPTER_NAME = "netty_observable_adapter";
private final BytesInspector bytesInspector;
private final EventExecutorGroup handlersExecutorGroup;
protected RxRequiredConfigurator(@SuppressWarnings("rawtypes") MetricEventsSubject eventsSubject,
ChannelMetricEventProvider metricEventProvider) {
this(eventsSubject, metricEventProvider, null);
}
/**
*
* @param eventsSubject Metrics event subject.
* @param metricEventProvider Metrics event provider.
* @param handlersExecutorGroup The {@link EventExecutorGroup} to be used for all the handlers added by this
* configurator. This can be {@code null} , in which case the eventloop for the
* underlying channel is used.
*/
protected RxRequiredConfigurator(@SuppressWarnings("rawtypes") MetricEventsSubject eventsSubject,
ChannelMetricEventProvider metricEventProvider,
EventExecutorGroup handlersExecutorGroup) {
bytesInspector = new BytesInspector(eventsSubject, metricEventProvider);
this.handlersExecutorGroup = handlersExecutorGroup;
}
@Override
public void configureNewPipeline(ChannelPipeline pipeline) {
/**
* This method is called for each new connection & the following two channel handlers are not shareable, so
* we need to create a new instance every time.
*/
ChannelHandler lifecycleHandler = newConnectionLifecycleHandler(pipeline);
ObservableAdapter observableAdapter = new ObservableAdapter();
pipeline.addFirst(BYTES_INSPECTOR_HANDLER_NAME, bytesInspector);
pipeline.addLast(getConnectionLifecycleHandlerExecutor(), CONN_LIFECYCLE_HANDLER_NAME, lifecycleHandler);
pipeline.addLast(getObservableAdapterExecutor(), NETTY_OBSERVABLE_ADAPTER_NAME, observableAdapter);
}
protected EventExecutorGroup getConnectionLifecycleHandlerExecutor() {
return handlersExecutorGroup;
}
protected EventExecutorGroup getObservableAdapterExecutor() {
return handlersExecutorGroup;
}
protected abstract ChannelHandler newConnectionLifecycleHandler(ChannelPipeline pipeline);
}