jlibs.wamp4j.netty.NettyWebSocketClient.java Source code

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Here is the source code for jlibs.wamp4j.netty.NettyWebSocketClient.java

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/**
 * Copyright 2015 Santhosh Kumar Tekuri
 *
 * The JLibs authors license this file to you 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 jlibs.wamp4j.netty;

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.http.DefaultHttpHeaders;
import io.netty.handler.codec.http.HttpClientCodec;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.websocketx.*;
import jlibs.wamp4j.Util;
import jlibs.wamp4j.spi.ConnectListener;
import jlibs.wamp4j.spi.WebSocketClient;

import java.net.URI;
import java.util.concurrent.ThreadFactory;

/**
 * @author Santhosh Kumar Tekuri
 */
public class NettyWebSocketClient implements WebSocketClient {
    private static final NioEventLoopGroup eventLoopGroup = new NioEventLoopGroup(1, new ThreadFactory() {
        @Override
        public Thread newThread(Runnable r) {
            return new Thread(r, "NettyWebSocketClient");
        }
    });

    @Override
    public void connect(final URI uri, final ConnectListener listener, final String... subProtocols) {
        String protocol = uri.getScheme();
        if (!protocol.equals("ws"))
            throw new IllegalArgumentException("invalid protocol: " + protocol);
        int port = uri.getPort();
        if (port == -1)
            port = 80;

        Bootstrap bootstrap = new Bootstrap().group(eventLoopGroup).channel(NioSocketChannel.class)
                .handler(new ChannelInitializer<SocketChannel>() {
                    @Override
                    protected void initChannel(SocketChannel ch) throws Exception {
                        WebSocketClientHandshaker handshaker = WebSocketClientHandshakerFactory.newHandshaker(uri,
                                WebSocketVersion.V13, Util.toString(subProtocols), false, new DefaultHttpHeaders());
                        ch.pipeline().addLast(new HttpClientCodec(), new HttpObjectAggregator(8192),
                                new WebSocketClientProtocolHandler(handshaker),
                                new HandshakeListener(handshaker, listener));
                    }
                });
        bootstrap.connect(uri.getHost(), port).addListener(new ChannelFutureListener() {
            @Override
            public void operationComplete(ChannelFuture future) throws Exception {
                if (!future.isSuccess()) {
                    assert !future.channel().isOpen();
                    listener.onError(future.cause());
                }
            }
        });
    }

    @Override
    public boolean isEventLoop() {
        return eventLoopGroup.next().inEventLoop();
    }

    @Override
    public void submit(Runnable r) {
        eventLoopGroup.submit(r);
    }

    private static class HandshakeListener extends SimpleChannelInboundHandler<Object> {
        private final WebSocketClientHandshaker handshaker;
        private final ConnectListener connectListener;

        public HandshakeListener(WebSocketClientHandshaker handshaker, ConnectListener connectListener) {
            this.handshaker = handshaker;
            this.connectListener = connectListener;
        }

        @Override
        protected void channelRead0(ChannelHandlerContext ctx, Object msg) {
        }

        @Override
        public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
            if (handshaker.isHandshakeComplete()) {
                super.exceptionCaught(ctx, cause);
            } else {
                connectListener.onError(cause);
                ctx.close();
            }
        }

        @Override
        public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
            if (evt == WebSocketClientProtocolHandler.ClientHandshakeStateEvent.HANDSHAKE_COMPLETE) {
                NettyWebSocket webSocket = new NettyWebSocket(null, handshaker.actualSubprotocol());
                ctx.pipeline().addLast("ws-aggregator", new WebSocketFrameAggregator(16 * 1024 * 1024)); // 16MB
                ctx.pipeline().addLast("websocket", webSocket);
                ctx.pipeline().remove(this);
                webSocket.channelActive(ctx);
                connectListener.onConnect(webSocket);
            } else
                ctx.fireUserEventTriggered(evt);
        }
    }

}