/*
* 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.handler.codec.http.websocketx;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandler;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.channel.ChannelPipeline;
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.HttpResponseStatus;
import io.netty.util.AttributeKey;
import java.util.List;
import static io.netty.handler.codec.http.HttpVersion.*;
/**
* This handler does all the heavy lifting for you to run a websocket server.
*
* It takes care of websocket handshaking as well as processing of control frames (Close, Ping, Pong). Text and Binary
* data frames are passed to the next handler in the pipeline (implemented by you) for processing.
*
* See <tt>io.netty.example.http.websocketx.html5.WebSocketServer</tt> for usage.
*
* The implementation of this handler assumes that you just want to run a websocket server and not process other types
* HTTP requests (like GET and POST). If you wish to support both HTTP requests and websockets in the one server, refer
* to the <tt>io.netty.example.http.websocketx.server.WebSocketServer</tt> example.
*
* To know once a handshake was done you can intercept the
* {@link ChannelInboundHandler#userEventTriggered(ChannelHandlerContext, Object)} and check if the event was instance
* of {@link HandshakeComplete}, the event will contain extra information about the handshake such as the request and
* selected subprotocol.
*/
public class WebSocketServerProtocolHandler extends WebSocketProtocolHandler {
/**
* Events that are fired to notify about handshake status
*/
public enum ServerHandshakeStateEvent {
/**
* The Handshake was completed successfully and the channel was upgraded to websockets.
*
* @deprecated in favor of {@link HandshakeComplete} class,
* it provides extra information about the handshake
*/
@Deprecated
HANDSHAKE_COMPLETE
}
/**
* The Handshake was completed successfully and the channel was upgraded to websockets.
*/
public static final class HandshakeComplete {
private final String requestUri;
private final HttpHeaders requestHeaders;
private final String selectedSubprotocol;
HandshakeComplete(String requestUri, HttpHeaders requestHeaders, String selectedSubprotocol) {
this.requestUri = requestUri;
this.requestHeaders = requestHeaders;
this.selectedSubprotocol = selectedSubprotocol;
}
public String requestUri() {
return requestUri;
}
public HttpHeaders requestHeaders() {
return requestHeaders;
}
public String selectedSubprotocol() {
return selectedSubprotocol;
}
}
private static final AttributeKey<WebSocketServerHandshaker> HANDSHAKER_ATTR_KEY =
AttributeKey.valueOf(WebSocketServerHandshaker.class, "HANDSHAKER");
private final String websocketPath;
private final String subprotocols;
private final boolean allowExtensions;
private final int maxFramePayloadLength;
private final boolean allowMaskMismatch;
private final boolean checkStartsWith;
public WebSocketServerProtocolHandler(String websocketPath) {
this(websocketPath, null, false);
}
public WebSocketServerProtocolHandler(String websocketPath, boolean checkStartsWith) {
this(websocketPath, null, false, 65536, false, checkStartsWith);
}
public WebSocketServerProtocolHandler(String websocketPath, String subprotocols) {
this(websocketPath, subprotocols, false);
}
public WebSocketServerProtocolHandler(String websocketPath, String subprotocols, boolean allowExtensions) {
this(websocketPath, subprotocols, allowExtensions, 65536);
}
public WebSocketServerProtocolHandler(String websocketPath, String subprotocols,
boolean allowExtensions, int maxFrameSize) {
this(websocketPath, subprotocols, allowExtensions, maxFrameSize, false);
}
public WebSocketServerProtocolHandler(String websocketPath, String subprotocols,
boolean allowExtensions, int maxFrameSize, boolean allowMaskMismatch) {
this(websocketPath, subprotocols, allowExtensions, maxFrameSize, allowMaskMismatch, false);
}
public WebSocketServerProtocolHandler(String websocketPath, String subprotocols,
boolean allowExtensions, int maxFrameSize, boolean allowMaskMismatch, boolean checkStartsWith) {
this.websocketPath = websocketPath;
this.subprotocols = subprotocols;
this.allowExtensions = allowExtensions;
maxFramePayloadLength = maxFrameSize;
this.allowMaskMismatch = allowMaskMismatch;
this.checkStartsWith = checkStartsWith;
}
@Override
public void handlerAdded(ChannelHandlerContext ctx) {
ChannelPipeline cp = ctx.pipeline();
if (cp.get(WebSocketServerProtocolHandshakeHandler.class) == null) {
// Add the WebSocketHandshakeHandler before this one.
ctx.pipeline().addBefore(ctx.name(), WebSocketServerProtocolHandshakeHandler.class.getName(),
new WebSocketServerProtocolHandshakeHandler(websocketPath, subprotocols,
allowExtensions, maxFramePayloadLength, allowMaskMismatch, checkStartsWith));
}
if (cp.get(Utf8FrameValidator.class) == null) {
// Add the UFT8 checking before this one.
ctx.pipeline().addBefore(ctx.name(), Utf8FrameValidator.class.getName(),
new Utf8FrameValidator());
}
}
@Override
protected void decode(ChannelHandlerContext ctx, WebSocketFrame frame, List<Object> out) throws Exception {
if (frame instanceof CloseWebSocketFrame) {
WebSocketServerHandshaker handshaker = getHandshaker(ctx.channel());
if (handshaker != null) {
frame.retain();
handshaker.close(ctx.channel(), (CloseWebSocketFrame) frame);
} else {
ctx.writeAndFlush(Unpooled.EMPTY_BUFFER).addListener(ChannelFutureListener.CLOSE);
}
return;
}
super.decode(ctx, frame, out);
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
if (cause instanceof WebSocketHandshakeException) {
FullHttpResponse response = new DefaultFullHttpResponse(
HTTP_1_1, HttpResponseStatus.BAD_REQUEST, Unpooled.wrappedBuffer(cause.getMessage().getBytes()));
ctx.channel().writeAndFlush(response).addListener(ChannelFutureListener.CLOSE);
} else {
ctx.fireExceptionCaught(cause);
ctx.close();
}
}
static WebSocketServerHandshaker getHandshaker(Channel channel) {
return channel.attr(HANDSHAKER_ATTR_KEY).get();
}
static void setHandshaker(Channel channel, WebSocketServerHandshaker handshaker) {
channel.attr(HANDSHAKER_ATTR_KEY).set(handshaker);
}
static ChannelHandler forbiddenHttpRequestResponder() {
return new ChannelInboundHandlerAdapter() {
@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
if (msg instanceof FullHttpRequest) {
((FullHttpRequest) msg).release();
FullHttpResponse response =
new DefaultFullHttpResponse(HTTP_1_1, HttpResponseStatus.FORBIDDEN);
ctx.channel().writeAndFlush(response);
} else {
ctx.fireChannelRead(msg);
}
}
};
}
}