netty.server.WebSocketServerHandler.java Source code

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/*
 * Copyright 2012 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 netty.server;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.websocketx.*;
import io.netty.util.CharsetUtil;
import netty.parser.Controller;
import netty.parser.ControllerChannel;
import netty.parser.SAXPars;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.Socket;
import java.nio.charset.StandardCharsets;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Scanner;
import java.util.concurrent.BlockingQueue;
import java.util.logging.Level;
import java.util.logging.Logger;

import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE;
import static io.netty.handler.codec.http.HttpHeaders.Names.HOST;
import static io.netty.handler.codec.http.HttpHeaders.isKeepAlive;
import static io.netty.handler.codec.http.HttpHeaders.setContentLength;
import static io.netty.handler.codec.http.HttpMethod.GET;
import static io.netty.handler.codec.http.HttpResponseStatus.*;
import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;

/**
 * Handles handshakes and messages
 */
public class WebSocketServerHandler extends SimpleChannelInboundHandler<Object> {
    private static final Logger logger = Logger.getLogger(WebSocketServerHandler.class.getName());
    private SAXPars pars;
    private Controller controller = null;
    private ControllerChannel controllerChannel = new ControllerChannel();
    private Socket socket;
    private Scanner scanner;
    private InputStream inStream;
    private String line;

    private static final String WEBSOCKET_PATH = "/websocket";

    private WebSocketServerHandshaker handshaker;
    private String controllerData = "";

    private BlockingQueue<Controller> controllerBlockingQueue;

    @Override
    public void messageReceived(ChannelHandlerContext ctx, Object msg) throws Exception {

        Date today = new Date(System.currentTimeMillis());
        DateFormat dateFormat = new SimpleDateFormat("dd-MM-yy:HH:mm:SS");
        String date = dateFormat.format(today);

        if (msg instanceof FullHttpRequest) {
            handleHttpRequest(ctx, (FullHttpRequest) msg);
        } else if (msg instanceof WebSocketFrame) {
            handleWebSocketFrame(ctx, (WebSocketFrame) msg);
        }
        //        System.out.println( ctx + " " + msg);
        System.out.println("Client " + date);
        // Close the connection if the client has sent '20'.
        if ("exit".equals(msg)) {
            ctx.close();
            System.out.println("  ? ");
        }

    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        //        System.out.println("ChannelHandlerContext" + ctx);
        ctx.flush();
    }

    private void handleHttpRequest(ChannelHandlerContext ctx, FullHttpRequest req) throws Exception {
        // Handle a bad request.
        if (!req.getDecoderResult().isSuccess()) {
            sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, BAD_REQUEST));
            return;
        }

        // Allow only GET methods.
        if (req.getMethod() != GET) {
            sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, FORBIDDEN));
            return;
        }

        // Send the list of controllers
        if (req.headers().contains("getList") && req.headers().get("getList") == "true") {
            // insert into response the list of controllers
            return;
        }

        // Receive the number of controller to send data
        if (req.headers().contains("choseController")) {
            String controllerNumber = req.headers().get("choseController");
            FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, OK, null);
            setContentLength(res, 0);
            sendHttpResponse(ctx, req, res);
            return;
        }

        // Send the demo page and favicon.ico
        if ("/".equals(req.getUri())) {
            ByteBuf content = WebSocketServerIndexPage.getContent(getWebSocketLocation(req));
            //            ByteBuf content = Unpooled.copiedBuffer(controllerData,CharsetUtil.UTF_8);
            FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, OK, content);

            res.headers().set(CONTENT_TYPE, "text/html; charset=UTF-8");
            setContentLength(res, content.readableBytes());

            sendHttpResponse(ctx, req, res);
            return;
        }
        if ("/favicon.ico".equals(req.getUri())) {
            FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, NOT_FOUND);
            sendHttpResponse(ctx, req, res);
            return;
        }

        // Handshake
        WebSocketServerHandshakerFactory wsFactory = new WebSocketServerHandshakerFactory(getWebSocketLocation(req),
                null, false);
        handshaker = wsFactory.newHandshaker(req);
        if (handshaker == null) {
            WebSocketServerHandshakerFactory.sendUnsupportedWebSocketVersionResponse(ctx.channel());
        } else {
            handshaker.handshake(ctx.channel(), req);
        }
    }

    private void handleWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame frame) throws Exception {

        // Check for closing frame
        if (frame instanceof CloseWebSocketFrame) {
            handshaker.close(ctx.channel(), (CloseWebSocketFrame) frame.retain());
            return;
        }
        if (frame instanceof PongWebSocketFrame) {
            ctx.channel().write(new PingWebSocketFrame(frame.content().retain()));
        }
        if (frame instanceof PingWebSocketFrame) {
            ctx.channel().write(new PongWebSocketFrame(frame.content().retain()));
            return;
        }
        if (!(frame instanceof TextWebSocketFrame)) {
            throw new UnsupportedOperationException(
                    String.format("%s frame types not supported", frame.getClass().getName()));
        }

        controllerData = ((TextWebSocketFrame) frame).text();
        if (controllerData != null) {
            System.out.println(controllerData);
            ctx.writeAndFlush(new TextWebSocketFrame(controllerData));
        }
        // Send the uppercase string back.
        sendStringBack(ctx, (TextWebSocketFrame) frame);
        // Close the connection if the client has sent '20'.
        if ("exit".equals(((TextWebSocketFrame) frame).text())) {
            ctx.close();
            System.out.println("  ? ");
            System.exit(0);
        }
    }

    private void sendStringBack(ChannelHandlerContext ctx, TextWebSocketFrame frame) throws Exception {
        String request = frame.text();
        if (logger.isLoggable(Level.FINE)) {
            logger.fine(String.format("%s received %s", ctx.channel(), request));
        }

        readInputStream();
        if (line != null) {
            //            System.out.println(line);
            ctx.channel().writeAndFlush(new TextWebSocketFrame(line));
        } else {
            ctx.channel().writeAndFlush(new TextWebSocketFrame("No data!"));
        }

        ctx.channel().writeAndFlush(new TextWebSocketFrame(request));
        System.out.println("Send the uppercase string back " + request);
    }

    private void readInputStream() throws ParserConfigurationException, SAXException, IOException {
        try {

            socket = new Socket("192.168.0.107", 33335);

            inStream = socket.getInputStream();

            scanner = new Scanner(inStream);

            //                scanner = new Scanner(new FileReader(new File(fileName)));

            while (scanner.hasNextLine()) {
                line = scanner.nextLine();
                System.out.println(line);
            }
            //                socket.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

        //        try {
        //            controller = controllerBlockingQueue.poll(50, TimeUnit.MILLISECONDS);
        //        } catch (InterruptedException e) {
        //            e.printStackTrace();
        //        }
        SAXParserFactory factory = SAXParserFactory.newInstance();
        SAXParser parser = factory.newSAXParser();
        SAXPars saxp = new SAXPars();

        InputStream stringStream = new ByteArrayInputStream(line.getBytes(StandardCharsets.UTF_8));
        parser.parse(new InputSource(stringStream), saxp);
    }

    private static void sendHttpResponse(ChannelHandlerContext ctx, FullHttpRequest req, FullHttpResponse res) {
        // Generate an error page if response getStatus code is not OK (200).
        if (res.getStatus().code() != 200) {
            ByteBuf buf = Unpooled.copiedBuffer(res.getStatus().toString(), CharsetUtil.UTF_8);
            res.content().writeBytes(buf);
            buf.release();
            setContentLength(res, res.content().readableBytes());
            //            System.out.println( "sendHttpResponse = " + res);
        }

        // Send the response and close the connection if necessary.
        ChannelFuture f = ctx.channel().writeAndFlush(res);
        if (!isKeepAlive(req) || res.getStatus().code() != 200) {
            f.addListener(ChannelFutureListener.CLOSE);
        }
    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        //        pars.startElement(msg);

        //        System.out.println("ChannelHandlerContext = " + ctx.name() + " Object = " + msg);

        super.channelRead(ctx, msg);
    }

    private static String getWebSocketLocation(FullHttpRequest req) {
        return "ws://" + req.headers().get(HOST) + WEBSOCKET_PATH;
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        cause.printStackTrace();
        ctx.close();
    }

}