Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF 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 org.apache.tinkerpop.gremlin.server.handler; import io.netty.channel.ChannelHandler; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; import io.netty.channel.ChannelPipeline; import io.netty.channel.EventLoopGroup; import io.netty.handler.codec.http.HttpMessage; import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler; import io.netty.handler.codec.http.HttpServerCodec; import org.apache.tinkerpop.gremlin.server.Channelizer; import org.apache.tinkerpop.gremlin.server.channel.HttpChannelizer; import org.apache.tinkerpop.gremlin.server.channel.WebSocketChannelizer; import org.apache.tinkerpop.gremlin.server.channel.WsAndHttpChannelizer; import org.apache.tinkerpop.gremlin.server.handler.HttpGremlinEndpointHandler; import org.apache.tinkerpop.gremlin.server.handler.WsAndHttpChannelizerHandler; import org.apache.tinkerpop.gremlin.server.handler.WebSocketHandlerUtil; import org.apache.tinkerpop.gremlin.server.util.ServerGremlinExecutor; import static io.netty.handler.codec.http.HttpHeaders.Names.UPGRADE; import static io.netty.handler.codec.http.HttpHeaders.Names.CONNECTION; import static org.apache.tinkerpop.gremlin.server.channel.WebSocketChannelizer.PIPELINE_AUTHENTICATOR; import static org.apache.tinkerpop.gremlin.server.channel.WebSocketChannelizer.PIPELINE_REQUEST_HANDLER; import static org.apache.tinkerpop.gremlin.server.channel.WebSocketChannelizer.PIPELINE_HTTP_RESPONSE_ENCODER; /** * A ChannelInboundHandlerAdapter for use with {@link WsAndHttpChannelizer} that toggles between WebSockets * and http. * * @author Keith Lohnes lohnesk@gmail.com */ @ChannelHandler.Sharable public class WsAndHttpChannelizerHandler extends ChannelInboundHandlerAdapter { private final WebSocketChannelizer wsChannelizer = new WebSocketChannelizer(); private HttpGremlinEndpointHandler httpGremlinEndpointHandler; public void init(final ServerGremlinExecutor serverGremlinExecutor, final HttpGremlinEndpointHandler httpGremlinEndpointHandler) { //WebSocketChannelizer has everything needed for the http endpoint to work wsChannelizer.init(serverGremlinExecutor); this.httpGremlinEndpointHandler = httpGremlinEndpointHandler; } public Channelizer getWsChannelizer() { return wsChannelizer; } public void configure(final ChannelPipeline pipeline) { wsChannelizer.configure(pipeline); } @Override public void channelRead(final ChannelHandlerContext ctx, final Object obj) { final ChannelPipeline pipeline = ctx.pipeline(); if (obj instanceof HttpMessage && !WebSocketHandlerUtil.isWebSocket((HttpMessage) obj)) { if (null != pipeline.get(PIPELINE_AUTHENTICATOR)) { pipeline.remove(PIPELINE_REQUEST_HANDLER); final ChannelHandler authenticator = pipeline.get(PIPELINE_AUTHENTICATOR); pipeline.remove(PIPELINE_AUTHENTICATOR); pipeline.addAfter(PIPELINE_HTTP_RESPONSE_ENCODER, PIPELINE_AUTHENTICATOR, authenticator); pipeline.addAfter(PIPELINE_AUTHENTICATOR, PIPELINE_REQUEST_HANDLER, this.httpGremlinEndpointHandler); } else { pipeline.remove(PIPELINE_REQUEST_HANDLER); pipeline.addAfter(PIPELINE_HTTP_RESPONSE_ENCODER, PIPELINE_REQUEST_HANDLER, this.httpGremlinEndpointHandler); } } ctx.fireChannelRead(obj); } @Override public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) { ctx.close(); } }