com.fanavard.challenge.client.websocket.WebSocketClient.java Source code

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Here is the source code for com.fanavard.challenge.client.websocket.WebSocketClient.java

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/*
 * Copyright 2014 The Netty Project
 *
 * The Netty Project licenses 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 com.fanavard.challenge.client.websocket;

import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.ChannelInitializer;
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.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.CloseWebSocketFrame;
import io.netty.handler.codec.http.websocketx.PingWebSocketFrame;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketClientHandshakerFactory;
import io.netty.handler.codec.http.websocketx.WebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketVersion;
import io.netty.handler.codec.http.websocketx.extensions.compression.WebSocketClientCompressionHandler;
import io.netty.handler.ssl.SslContext;
import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
import io.netty.handler.ssl.util.SelfSignedCertificate;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URI;

/**
 * This is an example of a WebSocket client.
 * <p>
 * In order to run this example you need a compatible WebSocket server.
 * Therefore you can either start the WebSocket server from the examples
 * by running {@link io.netty.example.http.websocketx.server.WebSocketServer}
 * or connect to an existing WebSocket server such as
 * <a href="http://www.websocket.org/echo.html">ws://echo.websocket.org</a>.
 * <p>
 * The client will attempt to connect to the URI passed to it as the first argument.
 * You don't have to specify any arguments if you want to connect to the example WebSocket server,
 * as this is the default.
 */
public final class WebSocketClient {

    static final String URL = System.getProperty("url", "ws://127.0.0.1:8080/websocket");

    public static void main(String[] args) throws Exception {
        URI uri = new URI(URL);
        String scheme = uri.getScheme() == null ? "http" : uri.getScheme();
        final String host = uri.getHost() == null ? "127.0.0.1" : uri.getHost();
        final int port;
        if (uri.getPort() == -1) {
            if ("http".equalsIgnoreCase(scheme)) {
                port = 80;
            } else if ("https".equalsIgnoreCase(scheme)) {
                port = 443;
            } else {
                port = -1;
            }
        } else {
            port = uri.getPort();
        }

        if (!"ws".equalsIgnoreCase(scheme) && !"wss".equalsIgnoreCase(scheme)) {
            System.err.println("Only WS(S) is supported.");
            return;
        }

        final boolean ssl = "wss".equalsIgnoreCase(scheme);
        final SslContext sslCtx;
        if (ssl) {
            sslCtx = SslContext.newClientContext(InsecureTrustManagerFactory.INSTANCE);
        } else {
            sslCtx = null;
        }

        EventLoopGroup group = new NioEventLoopGroup();
        try {
            // Connect with V13 (RFC 6455 aka HyBi-17). You can change it to V08 or V00.
            // If you change it to V00, ping is not supported and remember to change
            // HttpResponseDecoder to WebSocketHttpResponseDecoder in the pipeline.
            final WebSocketClientHandler handler = new WebSocketClientHandler(WebSocketClientHandshakerFactory
                    .newHandshaker(uri, WebSocketVersion.V13, null, false, new DefaultHttpHeaders()));

            Bootstrap b = new Bootstrap();
            b.group(group).channel(NioSocketChannel.class).handler(new ChannelInitializer<SocketChannel>() {
                @Override
                protected void initChannel(SocketChannel ch) {
                    ChannelPipeline p = ch.pipeline();
                    if (sslCtx != null) {
                        p.addLast(sslCtx.newHandler(ch.alloc(), host, port));
                    }
                    p.addLast(new HttpClientCodec(), new HttpObjectAggregator(8192),
                            new WebSocketClientCompressionHandler(), handler);
                }
            });

            Channel ch = b.connect(uri.getHost(), port).sync().channel();
            handler.handshakeFuture().sync();

            BufferedReader console = new BufferedReader(new InputStreamReader(System.in));
            while (true) {
                String msg = console.readLine();
                if (msg == null) {
                    break;
                } else if ("bye".equals(msg.toLowerCase())) {
                    ch.writeAndFlush(new CloseWebSocketFrame());
                    ch.closeFuture().sync();
                    break;
                } else if ("ping".equals(msg.toLowerCase())) {
                    WebSocketFrame frame = new PingWebSocketFrame(
                            Unpooled.wrappedBuffer(new byte[] { 8, 1, 8, 1 }));
                    ch.writeAndFlush(frame);
                } else {
                    WebSocketFrame frame = new TextWebSocketFrame(msg);
                    ch.writeAndFlush(frame);
                }
            }
        } finally {
            group.shutdownGracefully();
        }
    }
}