org.clitherproject.clither.server.net.WebSocketHandler.java Source code

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Here is the source code for org.clitherproject.clither.server.net.WebSocketHandler.java

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/**
 * This file is part of Clither.
 *
 * Clither is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Clither is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Clither.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.clitherproject.clither.server.net;

import com.google.common.net.HttpHeaders;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.websocketx.CloseWebSocketFrame;
import io.netty.handler.codec.http.websocketx.PingWebSocketFrame;
import io.netty.handler.codec.http.websocketx.PongWebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketServerHandshaker;
import io.netty.handler.codec.http.websocketx.WebSocketServerHandshakerFactory;

@SuppressWarnings("rawtypes")
public class WebSocketHandler extends SimpleChannelInboundHandler {

    private WebSocketServerHandshaker handshaker;

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, Object req) throws Exception {
        if (req instanceof FullHttpRequest) {
            FullHttpRequest request = (FullHttpRequest) req;
            // ----- Client authenticity check code -----
            String origin = request.headers().get(HttpHeaders.ORIGIN);
            if (origin != null) {
                switch (origin) {
                case "http://slither.io":
                case "https://slither.io":
                case "http://localhost":
                case "https://localhost":
                case "http://127.0.0.1":
                case "https://127.0.0.1":
                    break;
                default:
                    ctx.channel().close();
                    return;
                }
            }
            // -----/Client authenticity check code -----

            WebSocketServerHandshakerFactory wsFactory = new WebSocketServerHandshakerFactory(
                    "ws://" + request.headers().get(HttpHeaders.HOST) + "/", null, true);
            handshaker = wsFactory.newHandshaker(request);
            if (handshaker == null) {
                WebSocketServerHandshakerFactory.sendUnsupportedVersionResponse(ctx.channel());
            } else {
                handshaker.handshake(ctx.channel(), request);
            }
        } else if (req instanceof WebSocketFrame) {
            WebSocketFrame frame = (WebSocketFrame) req;

            if (req instanceof CloseWebSocketFrame) {
                if (handshaker != null) {
                    handshaker.close(ctx.channel(), ((CloseWebSocketFrame) req).retain());
                }
            } else if (req instanceof PingWebSocketFrame) {
                ctx.channel().write(new PongWebSocketFrame(frame.content().retain()));
            } else {
                ctx.fireChannelRead(frame.retain());
            }
        }
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        ctx.flush();
    }

}