org.restlet.engine.netty.NettyServerHelper.java Source code

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Here is the source code for org.restlet.engine.netty.NettyServerHelper.java

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/**
 * Copyright 2005-2016 Restlet
 * 
 * The contents of this file are subject to the terms of one of the following
 * open source licenses: Apache 2.0 or or EPL 1.0 (the "Licenses"). You can
 * select the license that you prefer but you may not use this file except in
 * compliance with one of these Licenses.
 * 
 * You can obtain a copy of the Apache 2.0 license at
 * http://www.opensource.org/licenses/apache-2.0
 * 
 * You can obtain a copy of the EPL 1.0 license at
 * http://www.opensource.org/licenses/eclipse-1.0
 * 
 * See the Licenses for the specific language governing permissions and
 * limitations under the Licenses.
 * 
 * Alternatively, you can obtain a royalty free commercial license with less
 * limitations, transferable or non-transferable, directly at
 * http://restlet.com/products/restlet-framework
 * 
 * Restlet is a registered trademark of Restlet S.A.S.
 */

package org.restlet.engine.netty;

import java.net.InetSocketAddress;

import org.reactivestreams.Processor;
import org.restlet.Server;
import org.restlet.engine.connector.ServerHelper;

import com.typesafe.netty.HandlerPublisher;
import com.typesafe.netty.HandlerSubscriber;
import com.typesafe.netty.http.HttpStreamsServerHandler;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.handler.codec.http.HttpRequestDecoder;
import io.netty.handler.codec.http.HttpResponse;
import io.netty.handler.codec.http.HttpResponseEncoder;

/**
 * Base Netty server connector. Here is the list of parameters that are
 * supported. They should be set in the Server's context before it is started:
 * <table>
 * <tr>
 * <th>Parameter name</th>
 * <th>Value type</th>
 * <th>Default value</th>
 * <th>Description</th>
 * </tr>
 * <tr>
 * <td>useForwardedForHeader</td>
 * <td>boolean</td>
 * <td>false</td>
 * <td>Lookup the "X-Forwarded-For" header supported by popular proxies and
 * caches and uses it to populate the Request.getClientAddresses() method
 * result. This information is only safe for intermediary components within your
 * local network. Other addresses could easily be changed by setting a fake
 * header and should not be trusted for serious security checks.</td>
 * </tr>
 * <tr>
 * <td>adapter</td>
 * <td>String</td>
 * <td>org.restlet.engine.adapter.ServerAdapter</td>
 * <td>Class name of the adapter of low-level HTTP calls into high level
 * requests and responses.</td>
 * </tr>
 * </table>
 * 
 * @author Jerome Louvel
 */
public abstract class NettyServerHelper extends ServerHelper implements Processor<HttpRequest, HttpResponse> {

    private ServerBootstrap serverBootstrap;

    private Channel serverChannel;

    private EventLoopGroup bossGroup;

    private EventLoopGroup workerGroup;

    private Processor<HttpRequest, HttpResponse> processor;

    /**
     * Constructor.
     * 
     * @param server
     *            The server to help.
     */
    public NettyServerHelper(Server server) {
        super(server);
    }

    protected EventLoopGroup getBossGroup() {
        return bossGroup;
    }

    public Processor<HttpRequest, HttpResponse> getProcessor() {
        return processor;
    }

    protected ServerBootstrap getServerBootstrap() {
        return serverBootstrap;
    }

    protected Channel getServerChannel() {
        return serverChannel;
    }

    protected EventLoopGroup getWorkerGroup() {
        return workerGroup;
    }

    protected void setBossGroup(EventLoopGroup eventGroup) {
        this.bossGroup = eventGroup;
    }

    public void setProcessor(Processor<HttpRequest, HttpResponse> processor) {
        this.processor = processor;
    }

    protected void setServerBootstrap(ServerBootstrap serverBootstrap) {
        this.serverBootstrap = serverBootstrap;
    }

    protected void setServerChannel(Channel channel) {
        this.serverChannel = channel;
    }

    protected void setWorkerGroup(EventLoopGroup workerGroup) {
        this.workerGroup = workerGroup;
    }

    @Override
    public void start() throws Exception {
        super.start();
        setBossGroup(new NioEventLoopGroup());
        setWorkerGroup(new NioEventLoopGroup());
        setServerBootstrap(new ServerBootstrap());
        getServerBootstrap().option(ChannelOption.SO_BACKLOG, 1024);
        getServerBootstrap().group(getBossGroup(), getWorkerGroup()).channel(NioServerSocketChannel.class)
                .childOption(ChannelOption.AUTO_READ, false).localAddress(getHelped().getPort())
                .childHandler(new ChannelInitializer<SocketChannel>() {
                    @Override
                    protected void initChannel(SocketChannel ch) throws Exception {
                        ChannelPipeline pipeline = ch.pipeline();

                        pipeline.addLast(new HttpRequestDecoder(), new HttpResponseEncoder())
                                .addLast("serverStreamsHandler", new HttpStreamsServerHandler());

                        HandlerSubscriber<HttpResponse> subscriber = new HandlerSubscriber<>(ch.eventLoop(), 2, 4);
                        HandlerPublisher<HttpRequest> publisher = new HandlerPublisher<>(ch.eventLoop(),
                                HttpRequest.class);

                        pipeline.addLast("serverSubscriber", subscriber);
                        pipeline.addLast("serverPublisher", publisher);

                        publisher.subscribe(NettyServerHelper.this);
                        NettyServerHelper.this.subscribe(subscriber);
                    }
                });

        setServerChannel(getServerBootstrap().bind().sync().channel());
        setEphemeralPort(((InetSocketAddress) getServerChannel().localAddress()).getPort());
        getLogger().info("Starting the Netty " + getProtocols() + " server on port " + getHelped().getPort());
    }

    @Override
    public void stop() throws Exception {
        getLogger().info("Stopping the Netty " + getProtocols() + " server on port " + getHelped().getPort());
        getServerChannel().close().sync();
        getBossGroup().shutdownGracefully();
        getWorkerGroup().shutdownGracefully();
        super.stop();
    }

}