/*
* 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.spdy;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelDuplexHandler;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelHandlerUtil;
import io.netty.channel.ChannelInboundByteHandler;
import io.netty.channel.ChannelInboundMessageHandler;
import io.netty.channel.ChannelPipeline;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpRequestDecoder;
import io.netty.handler.codec.http.HttpResponseEncoder;
import io.netty.handler.ssl.SslHandler;
import javax.net.ssl.SSLEngine;
/**
* {@link ChannelInboundByteHandler} which is responsible to setup the {@link ChannelPipeline} either for
* HTTP or SPDY. This offers an easy way for users to support both at the same time while not care to
* much about the low-level details.
*/
public abstract class SpdyOrHttpChooser extends ChannelDuplexHandler implements ChannelInboundByteHandler {
// TODO: Replace with generic NPN handler
public enum SelectedProtocol {
SPDY_2,
SPDY_3,
HTTP_1_1,
HTTP_1_0,
UNKNOWN
}
private final int maxSpdyContentLength;
private final int maxHttpContentLength;
protected SpdyOrHttpChooser(int maxSpdyContentLength, int maxHttpContentLength) {
this.maxSpdyContentLength = maxSpdyContentLength;
this.maxHttpContentLength = maxHttpContentLength;
}
/**
* Return the {@link SelectedProtocol} for the {@link SSLEngine}. If its not known yet implementations
* MUST return {@link SelectedProtocol#UNKNOWN}.
*
*/
protected abstract SelectedProtocol getProtocol(SSLEngine engine);
@Override
public ByteBuf newInboundBuffer(ChannelHandlerContext ctx) throws Exception {
return ChannelHandlerUtil.allocate(ctx);
}
@Override
public void discardInboundReadBytes(ChannelHandlerContext ctx) throws Exception {
// No need to discard anything because this handler will be replaced with something else very quickly.
}
@Override
public void freeInboundBuffer(ChannelHandlerContext ctx) throws Exception {
ctx.inboundByteBuffer().release();
}
@Override
public void inboundBufferUpdated(ChannelHandlerContext ctx) throws Exception {
if (initPipeline(ctx)) {
ctx.nextInboundByteBuffer().writeBytes(ctx.inboundByteBuffer());
// When we reached here we can remove this handler as its now clear what protocol we want to use
// from this point on.
ctx.pipeline().remove(this);
ctx.fireInboundBufferUpdated();
}
}
private boolean initPipeline(ChannelHandlerContext ctx) {
// Get the SslHandler from the ChannelPipeline so we can obtain the SslEngine from it.
SslHandler handler = ctx.pipeline().get(SslHandler.class);
if (handler == null) {
// SslHandler is needed by SPDY by design.
throw new IllegalStateException("SslHandler is needed for SPDY");
}
SelectedProtocol protocol = getProtocol(handler.engine());
switch (protocol) {
case UNKNOWN:
// Not done with choosing the protocol, so just return here for now,
return false;
case SPDY_2:
addSpdyHandlers(ctx, 2);
break;
case SPDY_3:
addSpdyHandlers(ctx, 3);
break;
case HTTP_1_0:
case HTTP_1_1:
addHttpHandlers(ctx);
break;
default:
throw new IllegalStateException("Unknown SelectedProtocol");
}
return true;
}
/**
* Add all {@link ChannelHandler}'s that are needed for SPDY with the given version.
*/
protected void addSpdyHandlers(ChannelHandlerContext ctx, int version) {
ChannelPipeline pipeline = ctx.pipeline();
pipeline.addLast("spdyDecoder", new SpdyFrameDecoder(version));
pipeline.addLast("spdyEncoder", new SpdyFrameEncoder(version));
pipeline.addLast("spdySessionHandler", new SpdySessionHandler(version, true));
pipeline.addLast("spdyHttpEncoder", new SpdyHttpEncoder(version));
pipeline.addLast("spdyHttpDecoder", new SpdyHttpDecoder(version, maxSpdyContentLength));
pipeline.addLast("spdyStreamIdHandler", new SpdyHttpResponseStreamIdHandler());
pipeline.addLast("httpRquestHandler", createHttpRequestHandlerForSpdy());
}
/**
* Add all {@link ChannelHandler}'s that are needed for HTTP.
*/
protected void addHttpHandlers(ChannelHandlerContext ctx) {
ChannelPipeline pipeline = ctx.pipeline();
pipeline.addLast("httpRquestDecoder", new HttpRequestDecoder());
pipeline.addLast("httpResponseEncoder", new HttpResponseEncoder());
pipeline.addLast("httpChunkAggregator", new HttpObjectAggregator(maxHttpContentLength));
pipeline.addLast("httpRquestHandler", createHttpRequestHandlerForHttp());
}
/**
* Create the {@link ChannelInboundMessageHandler} that is responsible for handling the http requests
* when the {@link SelectedProtocol} was {@link SelectedProtocol#HTTP_1_0} or
* {@link SelectedProtocol#HTTP_1_1}
*/
protected abstract ChannelInboundMessageHandler<?> createHttpRequestHandlerForHttp();
/**
* Create the {@link ChannelInboundMessageHandler} that is responsible for handling the http responses
* when the {@link SelectedProtocol} was {@link SelectedProtocol#SPDY_2} or
* {@link SelectedProtocol#SPDY_3}.
*
* Bye default this getMethod will just delecate to {@link #createHttpRequestHandlerForHttp()}, but
* sub-classes may override this to change the behaviour.
*/
protected ChannelInboundMessageHandler<?> createHttpRequestHandlerForSpdy() {
return createHttpRequestHandlerForHttp();
}
}