/*
* Copyright 2011 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.example.http.websocketx.autobahn;
import static io.netty.handler.codec.http.HttpHeaders.*;
import static io.netty.handler.codec.http.HttpMethod.*;
import static io.netty.handler.codec.http.HttpResponseStatus.*;
import static io.netty.handler.codec.http.HttpVersion.*;
import io.netty.buffer.ChannelBuffers;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ExceptionEvent;
import io.netty.channel.MessageEvent;
import io.netty.channel.SimpleChannelUpstreamHandler;
import io.netty.handler.codec.http.DefaultHttpResponse;
import io.netty.handler.codec.http.HttpHeaders;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.handler.codec.http.HttpResponse;
import io.netty.handler.codec.http.websocketx.BinaryWebSocketFrame;
import io.netty.handler.codec.http.websocketx.CloseWebSocketFrame;
import io.netty.handler.codec.http.websocketx.ContinuationWebSocketFrame;
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.logging.InternalLogger;
import io.netty.logging.InternalLoggerFactory;
import io.netty.util.CharsetUtil;
/**
* Handles handshakes and messages
*/
public class AutobahnServerHandler extends SimpleChannelUpstreamHandler {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(AutobahnServerHandler.class);
private WebSocketServerHandshaker handshaker;
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {
Object msg = e.getMessage();
if (msg instanceof HttpRequest) {
handleHttpRequest(ctx, (HttpRequest) msg);
} else if (msg instanceof WebSocketFrame) {
handleWebSocketFrame(ctx, (WebSocketFrame) msg);
}
}
private void handleHttpRequest(ChannelHandlerContext ctx, HttpRequest req) throws Exception {
// Allow only GET methods.
if (req.getMethod() != GET) {
sendHttpResponse(ctx, req, new DefaultHttpResponse(HTTP_1_1, FORBIDDEN));
return;
}
// Handshake
WebSocketServerHandshakerFactory wsFactory = new WebSocketServerHandshakerFactory(
this.getWebSocketLocation(req), null, false);
this.handshaker = wsFactory.newHandshaker(req);
if (this.handshaker == null) {
wsFactory.sendUnsupportedWebSocketVersionResponse(ctx.getChannel());
} else {
this.handshaker.handshake(ctx.getChannel(), req);
}
}
private void handleWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame frame) {
if (logger.isDebugEnabled()) {
logger.debug(String
.format("Channel %s received %s", ctx.getChannel().getId(), frame.getClass().getSimpleName()));
}
if (frame instanceof CloseWebSocketFrame) {
this.handshaker.close(ctx.getChannel(), (CloseWebSocketFrame) frame);
} else if (frame instanceof PingWebSocketFrame) {
ctx.getChannel().write(
new PongWebSocketFrame(frame.isFinalFragment(), frame.getRsv(), frame.getBinaryData()));
} else if (frame instanceof TextWebSocketFrame) {
// String text = ((TextWebSocketFrame) frame).getText();
ctx.getChannel().write(
new TextWebSocketFrame(frame.isFinalFragment(), frame.getRsv(), frame.getBinaryData()));
} else if (frame instanceof BinaryWebSocketFrame) {
ctx.getChannel().write(
new BinaryWebSocketFrame(frame.isFinalFragment(), frame.getRsv(), frame.getBinaryData()));
} else if (frame instanceof ContinuationWebSocketFrame) {
ctx.getChannel().write(
new ContinuationWebSocketFrame(frame.isFinalFragment(), frame.getRsv(), frame.getBinaryData()));
} else if (frame instanceof PongWebSocketFrame) {
// Ignore
} else {
throw new UnsupportedOperationException(String.format("%s frame types not supported", frame.getClass()
.getName()));
}
}
private void sendHttpResponse(ChannelHandlerContext ctx, HttpRequest req, HttpResponse res) {
// Generate an error page if response status code is not OK (200).
if (res.getStatus().getCode() != 200) {
res.setContent(ChannelBuffers.copiedBuffer(res.getStatus().toString(), CharsetUtil.UTF_8));
setContentLength(res, res.getContent().readableBytes());
}
// Send the response and close the connection if necessary.
ChannelFuture f = ctx.getChannel().write(res);
if (!isKeepAlive(req) || res.getStatus().getCode() != 200) {
f.addListener(ChannelFutureListener.CLOSE);
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) throws Exception {
e.getCause().printStackTrace();
e.getChannel().close();
}
private String getWebSocketLocation(HttpRequest req) {
return "ws://" + req.getHeader(HttpHeaders.Names.HOST);
}
}