/*
* 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 com.facebook.presto.jdbc.internal.netty.handler.codec.spdy;
import javax.net.ssl.SSLEngine;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelEvent;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelHandler;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelHandlerContext;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelPipeline;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelUpstreamHandler;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpChunkAggregator;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpRequest;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpRequestDecoder;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpResponseEncoder;
import com.facebook.presto.jdbc.internal.netty.handler.ssl.SslHandler;
/**
* {@link ChannelUpstreamHandler} 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 implements ChannelUpstreamHandler {
public enum SelectedProtocol {
SpdyVersion2,
SpdyVersion3,
HttpVersion1_1,
HttpVersion1_0,
None
}
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#None}.
*
*/
protected abstract SelectedProtocol getProtocol(SSLEngine engine);
public void handleUpstream(ChannelHandlerContext ctx, ChannelEvent e) throws Exception {
// Get the SslHandler from the ChannelPipeline so we can obtain the SslEngine from it.
SslHandler handler = ctx.getPipeline().get(SslHandler.class);
if (handler == null) {
// SslHandler is needed by SPDY by design.
throw new IllegalStateException("SslHandler is needed for SPDY");
}
ChannelPipeline pipeline = ctx.getPipeline();
SelectedProtocol protocol = getProtocol(handler.getEngine());
switch (protocol) {
case None:
// Not done with choosing the protocol, so just return here for now,
return;
case SpdyVersion2:
addSpdyHandlers(ctx, 2);
break;
case SpdyVersion3:
addSpdyHandlers(ctx, 3);
break;
case HttpVersion1_0:
case HttpVersion1_1:
addHttpHandlers(ctx);
break;
default:
throw new IllegalStateException("Unknown SelectedProtocol");
}
// When we reached here we can remove this handler as its now clear what protocol we want to use
// from this point on.
pipeline.remove(this);
ctx.sendUpstream(e);
}
/**
* Add all {@link ChannelHandler}'s that are needed for SPDY with the given version.
*/
protected void addSpdyHandlers(ChannelHandlerContext ctx, int version) {
ChannelPipeline pipeline = ctx.getPipeline();
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.getPipeline();
pipeline.addLast("httpRquestDecoder", new HttpRequestDecoder());
pipeline.addLast("httpResponseEncoder", new HttpResponseEncoder());
pipeline.addLast("httpChunkAggregator", new HttpChunkAggregator(maxHttpContentLength));
pipeline.addLast("httpRquestHandler", createHttpRequestHandlerForHttp());
}
/**
* Create the {@link ChannelUpstreamHandler} that is responsible for handling the {@link HttpRequest}'s
* when the {@link SelectedProtocol} was {@link SelectedProtocol#HttpVersion1_0} or
* {@link SelectedProtocol#HttpVersion1_1}
*/
protected abstract ChannelUpstreamHandler createHttpRequestHandlerForHttp();
/**
* Create the {@link ChannelUpstreamHandler} that is responsible for handling the {@link HttpRequest}'s
* when the {@link SelectedProtocol} was {@link SelectedProtocol#SpdyVersion2} or
* {@link SelectedProtocol#SpdyVersion3}.
*
* Bye default this method will just delecate to {@link #createHttpRequestHandlerForHttp()}, but
* sub-classes may override this to change the behaviour.
*/
protected ChannelUpstreamHandler createHttpRequestHandlerForSpdy() {
return createHttpRequestHandlerForHttp();
}
}