HttpClientUpgradeHandler.java — netty Source File

Source Code

/*
 * 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:
 *
 * https://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;

import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandler;
import io.netty.channel.ChannelPromise;
import io.netty.util.AsciiString;
import io.netty.util.ReferenceCountUtil;
import io.netty.util.internal.ObjectUtil;

import java.net.SocketAddress;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;

import static io.netty.handler.codec.http.HttpResponseStatus.SWITCHING_PROTOCOLS;
import static io.netty.util.ReferenceCountUtil.release;

/**
 * Client-side handler for handling an HTTP upgrade handshake to another protocol. When the first
 * HTTP request is sent, this handler will add all appropriate headers to perform an upgrade to the
 * new protocol. If the upgrade fails (i.e. response is not 101 Switching Protocols), this handler
 * simply removes itself from the pipeline. If the upgrade is successful, upgrades the pipeline to
 * the new protocol.
 */
public class HttpClientUpgradeHandler extends HttpObjectAggregator implements ChannelOutboundHandler {

    /**
     * User events that are fired to notify about upgrade status.
     */
    public enum UpgradeEvent {
        /**
         * The Upgrade request was sent to the server.
         */
        UPGRADE_ISSUED,

        /**
         * The Upgrade to the new protocol was successful.
         */
        UPGRADE_SUCCESSFUL,

        /**
         * The Upgrade was unsuccessful due to the server not issuing
         * with a 101 Switching Protocols response.
         */
        UPGRADE_REJECTED
// ... (225 more lines)