All Downloads are FREE. Search and download functionalities are using the official Maven repository.

io.netty.handler.codec.http.websocketx.WebSocketClientProtocolHandler Maven / Gradle / Ivy

Go to download

This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

There is a newer version: 33.0.2.Final
Show newest version
/*
 * Copyright 2013 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 io.netty.handler.codec.http.websocketx;

import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandler;
import io.netty.channel.ChannelPipeline;
import io.netty.handler.codec.http.HttpHeaders;

import java.net.URI;
import java.util.List;

/**
 * This handler does all the heavy lifting for you to run a websocket client.
 *
 * It takes care of websocket handshaking as well as processing of Ping, Pong frames. Text and Binary
 * data frames are passed to the next handler in the pipeline (implemented by you) for processing.
 * Also the close frame is passed to the next handler as you may want inspect it before close the connection if
 * the {@code handleCloseFrames} is {@code false}, default is {@code true}.
 *
 * This implementation will establish the websocket connection once the connection to the remote server was complete.
 *
 * To know once a handshake was done you can intercept the
 * {@link ChannelInboundHandler#userEventTriggered(ChannelHandlerContext, Object)} and check if the event was of type
 * {@link ClientHandshakeStateEvent#HANDSHAKE_ISSUED} or {@link ClientHandshakeStateEvent#HANDSHAKE_COMPLETE}.
 */
public class WebSocketClientProtocolHandler extends WebSocketProtocolHandler {

    private final WebSocketClientHandshaker handshaker;
    private final boolean handleCloseFrames;

    /**
     * Returns the used handshaker
     */
    public WebSocketClientHandshaker handshaker() { return handshaker; }

    /**
     * Events that are fired to notify about handshake status
     */
    public enum ClientHandshakeStateEvent {
        /**
         * The Handshake was started but the server did not response yet to the request
         */
        HANDSHAKE_ISSUED,

        /**
         * The Handshake was complete succesful and so the channel was upgraded to websockets
         */
        HANDSHAKE_COMPLETE
    }

    /**
     * Base constructor
     *
     * @param webSocketURL
     *            URL for web socket communications. e.g "ws://myhost.com/mypath". Subsequent web socket frames will be
     *            sent to this URL.
     * @param version
     *            Version of web socket specification to use to connect to the server
     * @param subprotocol
     *            Sub protocol request sent to the server.
     * @param customHeaders
     *            Map of custom headers to add to the client request
     * @param maxFramePayloadLength
     *            Maximum length of a frame's payload
     * @param handleCloseFrames
     *            {@code true} if close frames should not be forwarded and just close the channel
     */
    public WebSocketClientProtocolHandler(URI webSocketURL, WebSocketVersion version, String subprotocol,
                                                   boolean allowExtensions, HttpHeaders customHeaders,
                                                   int maxFramePayloadLength, boolean handleCloseFrames) {
        this(WebSocketClientHandshakerFactory.newHandshaker(webSocketURL, version, subprotocol,
                allowExtensions, customHeaders, maxFramePayloadLength), handleCloseFrames);
    }

    /**
     * Base constructor
     *
     * @param webSocketURL
     *            URL for web socket communications. e.g "ws://myhost.com/mypath". Subsequent web socket frames will be
     *            sent to this URL.
     * @param version
     *            Version of web socket specification to use to connect to the server
     * @param subprotocol
     *            Sub protocol request sent to the server.
     * @param customHeaders
     *            Map of custom headers to add to the client request
     * @param maxFramePayloadLength
     *            Maximum length of a frame's payload
     */
    public WebSocketClientProtocolHandler(URI webSocketURL, WebSocketVersion version, String subprotocol,
                                          boolean allowExtensions, HttpHeaders customHeaders,
                                          int maxFramePayloadLength) {
        this(webSocketURL, version, subprotocol,
                allowExtensions, customHeaders, maxFramePayloadLength, true);
    }

    /**
     * Base constructor
     *
     * @param handshaker
     *            The {@link WebSocketClientHandshaker} which will be used to issue the handshake once the connection
     *            was established to the remote peer.
     * @param handleCloseFrames
     *            {@code true} if close frames should not be forwarded and just close the channel
     */
    public WebSocketClientProtocolHandler(WebSocketClientHandshaker handshaker, boolean handleCloseFrames) {
        this.handshaker = handshaker;
        this.handleCloseFrames = handleCloseFrames;
    }

    /**
     * Base constructor
     *
     * @param handshaker
     *            The {@link WebSocketClientHandshaker} which will be used to issue the handshake once the connection
     *            was established to the remote peer.
     */
    public WebSocketClientProtocolHandler(WebSocketClientHandshaker handshaker) {
        this(handshaker, true);
    }

    @Override
    protected void decode(ChannelHandlerContext ctx, WebSocketFrame frame, List out) throws Exception {
        if (handleCloseFrames && frame instanceof CloseWebSocketFrame) {
            ctx.close();
            return;
        }
        super.decode(ctx, frame, out);
    }

    @Override
    public void handlerAdded(ChannelHandlerContext ctx) {
        ChannelPipeline cp = ctx.pipeline();
        if (cp.get(WebSocketClientProtocolHandshakeHandler.class) == null) {
            // Add the WebSocketClientProtocolHandshakeHandler before this one.
            ctx.pipeline().addBefore(ctx.name(), WebSocketClientProtocolHandshakeHandler.class.getName(),
                    new WebSocketClientProtocolHandshakeHandler(handshaker));
        }
    }
}