/*
* Copyright 2012 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 io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundMessageHandlerAdapter;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpHeaders;
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.util.CharsetUtil;
import java.util.logging.Level;
import java.util.logging.Logger;
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.*;
/**
* Handles handshakes and messages
*/
public class AutobahnServerHandler extends ChannelInboundMessageHandlerAdapter<Object> {
private static final Logger logger = Logger.getLogger(AutobahnServerHandler.class.getName());
private WebSocketServerHandshaker handshaker;
@Override
public void messageReceived(ChannelHandlerContext ctx, Object msg) throws Exception {
if (msg instanceof FullHttpRequest) {
handleHttpRequest(ctx, (FullHttpRequest) msg);
} else if (msg instanceof WebSocketFrame) {
handleWebSocketFrame(ctx, (WebSocketFrame) msg);
}
}
private void handleHttpRequest(ChannelHandlerContext ctx, FullHttpRequest req) throws Exception {
// Handle a bad request.
if (!req.getDecoderResult().isSuccess()) {
sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, BAD_REQUEST));
return;
}
// Allow only GET methods.
if (req.getMethod() != GET) {
sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, FORBIDDEN));
return;
}
// Handshake
WebSocketServerHandshakerFactory wsFactory = new WebSocketServerHandshakerFactory(
getWebSocketLocation(req), null, false, Integer.MAX_VALUE);
handshaker = wsFactory.newHandshaker(req);
if (handshaker == null) {
WebSocketServerHandshakerFactory.sendUnsupportedWebSocketVersionResponse(ctx.channel());
} else {
handshaker.handshake(ctx.channel(), req);
}
}
private void handleWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame frame) {
if (logger.isLoggable(Level.FINE)) {
logger.fine(String.format(
"Channel %s received %s", ctx.channel().id(), frame.getClass().getSimpleName()));
}
if (frame instanceof CloseWebSocketFrame) {
handshaker.close(ctx.channel(), (CloseWebSocketFrame) frame.retain());
} else if (frame instanceof PingWebSocketFrame) {
ctx.nextOutboundMessageBuffer().add(
new PongWebSocketFrame(frame.isFinalFragment(), frame.rsv(), frame.data().retain()));
} else if (frame instanceof TextWebSocketFrame) {
ctx.nextOutboundMessageBuffer().add(frame.retain());
} else if (frame instanceof BinaryWebSocketFrame) {
ctx.nextOutboundMessageBuffer().add(frame.retain());
} else if (frame instanceof ContinuationWebSocketFrame) {
ctx.nextOutboundMessageBuffer().add(frame.retain());
} else if (frame instanceof PongWebSocketFrame) {
// Ignore
} else {
throw new UnsupportedOperationException(String.format("%s frame types not supported", frame.getClass()
.getName()));
}
}
@Override
public void endMessageReceived(ChannelHandlerContext ctx) throws Exception {
if (handshaker != null) {
ctx.flush().addListener(ChannelFutureListener.CLOSE_ON_FAILURE);
}
}
private static void sendHttpResponse(
ChannelHandlerContext ctx, FullHttpRequest req, FullHttpResponse res) {
// Generate an error page if response getStatus code is not OK (200).
if (res.getStatus().code() != 200) {
res.data().writeBytes(Unpooled.copiedBuffer(res.getStatus().toString(), CharsetUtil.UTF_8));
setContentLength(res, res.data().readableBytes());
}
// Send the response and close the connection if necessary.
ChannelFuture f = ctx.channel().write(res);
if (!isKeepAlive(req) || res.getStatus().code() != 200) {
f.addListener(ChannelFutureListener.CLOSE);
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
cause.printStackTrace();
ctx.close();
}
private static String getWebSocketLocation(FullHttpRequest req) {
return "ws://" + req.headers().get(HttpHeaders.Names.HOST);
}
}