Java tutorial
/** * Copyright 2012 Ronen Hamias, Anton Kharenko * * Licensed 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.scalecube.socketio.pipeline; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.net.SocketAddress; import java.util.Map; import java.util.concurrent.ConcurrentHashMap; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelFutureListener; import io.netty.channel.ChannelHandler; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; import io.netty.handler.codec.http.FullHttpRequest; import io.netty.handler.codec.http.HttpHeaders; import io.netty.handler.codec.http.HttpMethod; import io.netty.handler.codec.http.HttpRequest; import io.netty.handler.codec.http.QueryStringDecoder; 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.TextWebSocketFrame; import io.netty.handler.codec.http.websocketx.WebSocketFrame; import io.netty.handler.codec.http.websocketx.WebSocketServerHandshaker; import io.netty.handler.codec.http.websocketx.WebSocketServerHandshakerFactory; import io.netty.util.ReferenceCountUtil; import io.scalecube.socketio.TransportType; import io.scalecube.socketio.packets.ConnectPacket; import io.scalecube.socketio.packets.Packet; import io.scalecube.socketio.serialization.PacketDecoder; /** * * @author Anton Kharenko * */ @ChannelHandler.Sharable public class WebSocketHandler extends ChannelInboundHandlerAdapter { private final Logger log = LoggerFactory.getLogger(getClass()); private final Map<Object, String> sessionIdByChannel = new ConcurrentHashMap<Object, String>(); private final String connectPath; private final boolean secure; private final String remoteAddressHeader; private final int maxWebSocketFrameSize; public WebSocketHandler(final String handshakePath, final boolean secure, final int maxWebSocketFrameSize, final String remoteAddressHeader) { this.connectPath = handshakePath + getTransportType().getName(); this.secure = secure; this.remoteAddressHeader = remoteAddressHeader; this.maxWebSocketFrameSize = maxWebSocketFrameSize; } protected TransportType getTransportType() { return TransportType.WEBSOCKET; } @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { // ? if (msg instanceof FullHttpRequest) { FullHttpRequest req = (FullHttpRequest) msg; if (req.getMethod() == HttpMethod.GET && req.getUri().startsWith(connectPath)) { final QueryStringDecoder queryDecoder = new QueryStringDecoder(req.getUri()); final String requestPath = queryDecoder.path(); if (log.isDebugEnabled()) log.debug("Received HTTP {} handshake request: {} {} from channel: {}", getTransportType().getName(), req.getMethod(), requestPath, ctx.channel()); handshake(ctx, req, requestPath); ReferenceCountUtil.release(msg); return; } } else if (msg instanceof WebSocketFrame && isCurrentHandlerSession(ctx)) { handleWebSocketFrame(ctx, (WebSocketFrame) msg); return; } ctx.fireChannelRead(msg); } @Override public void channelInactive(ChannelHandlerContext ctx) throws Exception { sessionIdByChannel.remove(ctx.channel()); super.channelInactive(ctx); } private boolean isCurrentHandlerSession(ChannelHandlerContext ctx) { return sessionIdByChannel.containsKey(ctx.channel()); } private boolean handshake(final ChannelHandlerContext ctx, final FullHttpRequest req, final String requestPath) { WebSocketServerHandshakerFactory wsFactory = new WebSocketServerHandshakerFactory(getWebSocketLocation(req), null, false, maxWebSocketFrameSize); WebSocketServerHandshaker handshaker = wsFactory.newHandshaker(req); if (handshaker != null) { handshaker.handshake(ctx.channel(), req).addListener(new ChannelFutureListener() { @Override public void operationComplete(ChannelFuture future) throws Exception { if (future.isSuccess()) { final String sessionId = PipelineUtils.getSessionId(requestPath); connect(ctx, req, sessionId); } } }); return true; } else { WebSocketServerHandshakerFactory.sendUnsupportedVersionResponse(ctx.channel()); } return false; } private String getWebSocketLocation(HttpRequest req) { String protocol = secure ? "wss://" : "ws://"; String webSocketLocation = protocol + req.headers().get(HttpHeaders.Names.HOST) + req.getUri(); if (log.isDebugEnabled()) log.debug("Created {} at: {}", getTransportType().getName(), webSocketLocation); return webSocketLocation; } private void connect(ChannelHandlerContext ctx, HttpRequest req, String sessionId) throws Exception { sessionIdByChannel.put(ctx.channel(), sessionId); SocketAddress clientIp = PipelineUtils.getHeaderClientIPParamValue(req, remoteAddressHeader); final ConnectPacket packet = new ConnectPacket(sessionId, PipelineUtils.getOrigin(req)); packet.setTransportType(getTransportType()); packet.setRemoteAddress(clientIp); ctx.fireChannelRead(packet); } private void handleWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame msg) throws Exception { if (log.isDebugEnabled()) log.debug("Received {} WebSocketFrame: {} from channel: {}", getTransportType().getName(), msg, ctx.channel()); if (msg instanceof CloseWebSocketFrame) { sessionIdByChannel.remove(ctx.channel()); ChannelFuture f = ctx.writeAndFlush(msg); f.addListener(ChannelFutureListener.CLOSE); return; } else if (msg instanceof PingWebSocketFrame) { ctx.writeAndFlush(new PongWebSocketFrame(msg.content())); return; } else if (!(msg instanceof TextWebSocketFrame)) { msg.release(); log.warn(String.format("%s frame types not supported", msg.getClass().getName())); return; } TextWebSocketFrame frame = (TextWebSocketFrame) msg; Packet packet = PacketDecoder.decodePacket(frame.content()); packet.setTransportType(getTransportType()); String sessionId = sessionIdByChannel.get(ctx.channel()); packet.setSessionId(sessionId); msg.release(); ctx.fireChannelRead(packet); } }