/*
* 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 com.facebook.presto.jdbc.internal.netty.buffer.ChannelBuffer;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelDownstreamHandler;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelEvent;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelFuture;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelFutureListener;
import com.facebook.presto.jdbc.internal.netty.channel.ChannelHandlerContext;
import com.facebook.presto.jdbc.internal.netty.channel.Channels;
import com.facebook.presto.jdbc.internal.netty.channel.DownstreamMessageEvent;
import com.facebook.presto.jdbc.internal.netty.channel.MessageEvent;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpChunk;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpChunkTrailer;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpHeaders;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpMessage;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpRequest;
import com.facebook.presto.jdbc.internal.netty.handler.codec.http.HttpResponse;
import java.net.SocketAddress;
import java.util.List;
import java.util.Map;
import static com.facebook.presto.jdbc.internal.netty.handler.codec.spdy.SpdyCodecUtil.*;
/**
* Encodes {@link HttpRequest}s, {@link HttpResponse}s, and {@link HttpChunk}s
* into {@link SpdySynStreamFrame}s and {@link SpdySynReplyFrame}s.
*
* <h3>Request Annotations</h3>
*
* SPDY specific headers must be added to {@link HttpRequest}s:
* <table border=1>
* <tr>
* <th>Header Name</th><th>Header Value</th>
* </tr>
* <tr>
* <td>{@code "X-SPDY-Stream-ID"}</td>
* <td>The Stream-ID for this request.
* Stream-IDs must be odd, positive integers, and must increase monotonically.</td>
* </tr>
* <tr>
* <td>{@code "X-SPDY-Priority"}</td>
* <td>The priority value for this request.
* The priority should be between 0 and 7 inclusive.
* 0 represents the highest priority and 7 represents the lowest.
* This header is optional and defaults to 0.</td>
* </tr>
* </table>
*
* <h3>Response Annotations</h3>
*
* SPDY specific headers must be added to {@link HttpResponse}s:
* <table border=1>
* <tr>
* <th>Header Name</th><th>Header Value</th>
* </tr>
* <tr>
* <td>{@code "X-SPDY-Stream-ID"}</td>
* <td>The Stream-ID of the request corresponding to this response.</td>
* </tr>
* </table>
*
* <h3>Pushed Resource Annotations</h3>
*
* SPDY specific headers must be added to pushed {@link HttpResponse}s:
* <table border=1>
* <tr>
* <th>Header Name</th><th>Header Value</th>
* </tr>
* <tr>
* <td>{@code "X-SPDY-Stream-ID"}</td>
* <td>The Stream-ID for this resource.
* Stream-IDs must be even, positive integers, and must increase monotonically.</td>
* </tr>
* <tr>
* <td>{@code "X-SPDY-Associated-To-Stream-ID"}</td>
* <td>The Stream-ID of the request that initiated this pushed resource.</td>
* </tr>
* <tr>
* <td>{@code "X-SPDY-Priority"}</td>
* <td>The priority value for this resource.
* The priority should be between 0 and 7 inclusive.
* 0 represents the highest priority and 7 represents the lowest.
* This header is optional and defaults to 0.</td>
* </tr>
* <tr>
* <td>{@code "X-SPDY-URL"}</td>
* <td>The absolute path for the resource being pushed.</td>
* </tr>
* </table>
*
* <h3>Required Annotations</h3>
*
* SPDY requires that all Requests and Pushed Resources contain
* an HTTP "Host" header.
*
* <h3>Optional Annotations</h3>
*
* Requests and Pushed Resources must contain a SPDY scheme header.
* This can be set via the {@code "X-SPDY-Scheme"} header but otherwise
* defaults to "https" as that is the most common SPDY deployment.
*
* <h3>Chunked Content</h3>
*
* This encoder associates all {@link HttpChunk}s that it receives
* with the most recently received 'chunked' {@link HttpRequest}
* or {@link HttpResponse}.
*
* <h3>Pushed Resources</h3>
*
* All pushed resources should be sent before sending the response
* that corresponds to the initial request.
*/
public class SpdyHttpEncoder implements ChannelDownstreamHandler {
private final int spdyVersion;
private volatile int currentStreamId;
/**
* Creates a new instance.
*
* @param version the protocol version
*/
public SpdyHttpEncoder(int version) {
if (version < SPDY_MIN_VERSION || version > SPDY_MAX_VERSION) {
throw new IllegalArgumentException(
"unsupported version: " + version);
}
spdyVersion = version;
}
public void handleDownstream(ChannelHandlerContext ctx, ChannelEvent evt)
throws Exception {
if (!(evt instanceof MessageEvent)) {
ctx.sendDownstream(evt);
return;
}
MessageEvent e = (MessageEvent) evt;
Object msg = e.getMessage();
if (msg instanceof HttpRequest) {
HttpRequest httpRequest = (HttpRequest) msg;
SpdySynStreamFrame spdySynStreamFrame = createSynStreamFrame(httpRequest);
currentStreamId = spdySynStreamFrame.getStreamId();
ChannelFuture future = getMessageFuture(ctx, e, currentStreamId, httpRequest);
Channels.write(ctx, future, spdySynStreamFrame, e.getRemoteAddress());
} else if (msg instanceof HttpResponse) {
HttpResponse httpResponse = (HttpResponse) msg;
if (httpResponse.containsHeader(SpdyHttpHeaders.Names.ASSOCIATED_TO_STREAM_ID)) {
SpdySynStreamFrame spdySynStreamFrame = createSynStreamFrame(httpResponse);
currentStreamId = spdySynStreamFrame.getStreamId();
ChannelFuture future = getMessageFuture(ctx, e, currentStreamId, httpResponse);
Channels.write(ctx, future, spdySynStreamFrame, e.getRemoteAddress());
} else {
SpdySynReplyFrame spdySynReplyFrame = createSynReplyFrame(httpResponse);
currentStreamId = spdySynReplyFrame.getStreamId();
ChannelFuture future = getMessageFuture(ctx, e, currentStreamId, httpResponse);
Channels.write(ctx, future, spdySynReplyFrame, e.getRemoteAddress());
}
} else if (msg instanceof HttpChunk) {
HttpChunk chunk = (HttpChunk) msg;
writeChunk(ctx, e.getFuture(), currentStreamId, chunk, e.getRemoteAddress());
} else {
// Unknown message type
ctx.sendDownstream(evt);
}
}
/**
* Writes an HTTP chunk downstream as one or more SPDY frames.
*/
protected void writeChunk(
ChannelHandlerContext ctx, ChannelFuture future,
int streamId, HttpChunk chunk, SocketAddress remoteAddress) {
if (chunk.isLast()) {
if (chunk instanceof HttpChunkTrailer) {
HttpChunkTrailer trailer = (HttpChunkTrailer) chunk;
List<Map.Entry<String, String>> trailers = trailer.getHeaders();
if (trailers.isEmpty()) {
SpdyDataFrame spdyDataFrame = new DefaultSpdyDataFrame(streamId);
spdyDataFrame.setLast(true);
Channels.write(ctx, future, spdyDataFrame, remoteAddress);
} else {
// Create SPDY HEADERS frame out of trailers
SpdyHeadersFrame spdyHeadersFrame = new DefaultSpdyHeadersFrame(streamId);
spdyHeadersFrame.setLast(true);
for (Map.Entry<String, String> entry: trailers) {
spdyHeadersFrame.addHeader(entry.getKey(), entry.getValue());
}
Channels.write(ctx, future, spdyHeadersFrame, remoteAddress);
}
} else {
SpdyDataFrame spdyDataFrame = new DefaultSpdyDataFrame(streamId);
spdyDataFrame.setLast(true);
Channels.write(ctx, future, spdyDataFrame, remoteAddress);
}
} else {
SpdyDataFrame[] spdyDataFrames = createSpdyDataFrames(streamId, chunk.getContent());
ChannelFuture dataFuture = getDataFuture(ctx, future, spdyDataFrames, remoteAddress);
// Trigger a write
dataFuture.setSuccess();
}
}
private ChannelFuture getMessageFuture(
ChannelHandlerContext ctx, MessageEvent e, int streamId, HttpMessage httpMessage) {
if (!httpMessage.getContent().readable()) {
return e.getFuture();
}
// Create SPDY Data Frames out of message content
SpdyDataFrame[] spdyDataFrames = createSpdyDataFrames(streamId, httpMessage.getContent());
if (spdyDataFrames.length > 0) {
spdyDataFrames[spdyDataFrames.length - 1].setLast(true);
}
return getDataFuture(ctx, e.getFuture(), spdyDataFrames, e.getRemoteAddress());
}
private static ChannelFuture getDataFuture(
ChannelHandlerContext ctx, ChannelFuture future,
SpdyDataFrame[] spdyDataFrames, SocketAddress remoteAddress) {
ChannelFuture dataFuture = future;
for (int i = spdyDataFrames.length; --i >= 0;) {
future = Channels.future(ctx.getChannel());
future.addListener(new SpdyFrameWriter(ctx, new DownstreamMessageEvent(
ctx.getChannel(), dataFuture, spdyDataFrames[i], remoteAddress)));
dataFuture = future;
}
return dataFuture;
}
private static class SpdyFrameWriter implements ChannelFutureListener {
private final ChannelHandlerContext ctx;
private final MessageEvent e;
SpdyFrameWriter(ChannelHandlerContext ctx, MessageEvent e) {
this.ctx = ctx;
this.e = e;
}
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess()) {
ctx.sendDownstream(e);
} else if (future.isCancelled()) {
e.getFuture().cancel();
} else {
e.getFuture().setFailure(future.getCause());
}
}
}
private SpdySynStreamFrame createSynStreamFrame(HttpMessage httpMessage)
throws Exception {
boolean chunked = httpMessage.isChunked();
// Get the Stream-ID, Associated-To-Stream-ID, Priority, URL, and scheme from the headers
int streamId = SpdyHttpHeaders.getStreamId(httpMessage);
int associatedToStreamId = SpdyHttpHeaders.getAssociatedToStreamId(httpMessage);
byte priority = SpdyHttpHeaders.getPriority(httpMessage);
String URL = SpdyHttpHeaders.getUrl(httpMessage);
String scheme = SpdyHttpHeaders.getScheme(httpMessage);
SpdyHttpHeaders.removeStreamId(httpMessage);
SpdyHttpHeaders.removeAssociatedToStreamId(httpMessage);
SpdyHttpHeaders.removePriority(httpMessage);
SpdyHttpHeaders.removeUrl(httpMessage);
SpdyHttpHeaders.removeScheme(httpMessage);
// The Connection, Keep-Alive, Proxy-Connection, and Transfer-Encoding
// headers are not valid and MUST not be sent.
httpMessage.removeHeader(HttpHeaders.Names.CONNECTION);
httpMessage.removeHeader("Keep-Alive");
httpMessage.removeHeader("Proxy-Connection");
httpMessage.removeHeader(HttpHeaders.Names.TRANSFER_ENCODING);
SpdySynStreamFrame spdySynStreamFrame =
new DefaultSpdySynStreamFrame(streamId, associatedToStreamId, priority);
spdySynStreamFrame.setLast(!chunked && !httpMessage.getContent().readable());
// Unfold the first line of the message into name/value pairs
if (httpMessage instanceof HttpRequest) {
HttpRequest httpRequest = (HttpRequest) httpMessage;
SpdyHeaders.setMethod(spdyVersion, spdySynStreamFrame, httpRequest.getMethod());
SpdyHeaders.setUrl(spdyVersion, spdySynStreamFrame, httpRequest.getUri());
SpdyHeaders.setVersion(spdyVersion, spdySynStreamFrame, httpMessage.getProtocolVersion());
}
if (httpMessage instanceof HttpResponse) {
HttpResponse httpResponse = (HttpResponse) httpMessage;
SpdyHeaders.setStatus(spdyVersion, spdySynStreamFrame, httpResponse.getStatus());
SpdyHeaders.setUrl(spdyVersion, spdySynStreamFrame, URL);
SpdyHeaders.setVersion(spdyVersion, spdySynStreamFrame, httpMessage.getProtocolVersion());
spdySynStreamFrame.setUnidirectional(true);
}
// Replace the HTTP host header with the SPDY host header
if (spdyVersion >= 3) {
String host = HttpHeaders.getHost(httpMessage);
httpMessage.removeHeader(HttpHeaders.Names.HOST);
SpdyHeaders.setHost(spdySynStreamFrame, host);
}
// Set the SPDY scheme header
if (scheme == null) {
scheme = "https";
}
SpdyHeaders.setScheme(spdyVersion, spdySynStreamFrame, scheme);
// Transfer the remaining HTTP headers
for (Map.Entry<String, String> entry: httpMessage.getHeaders()) {
spdySynStreamFrame.addHeader(entry.getKey(), entry.getValue());
}
return spdySynStreamFrame;
}
private SpdySynReplyFrame createSynReplyFrame(HttpResponse httpResponse)
throws Exception {
boolean chunked = httpResponse.isChunked();
// Get the Stream-ID from the headers
int streamId = SpdyHttpHeaders.getStreamId(httpResponse);
SpdyHttpHeaders.removeStreamId(httpResponse);
// The Connection, Keep-Alive, Proxy-Connection, and Transfer-Encoding
// headers are not valid and MUST not be sent.
httpResponse.removeHeader(HttpHeaders.Names.CONNECTION);
httpResponse.removeHeader("Keep-Alive");
httpResponse.removeHeader("Proxy-Connection");
httpResponse.removeHeader(HttpHeaders.Names.TRANSFER_ENCODING);
SpdySynReplyFrame spdySynReplyFrame = new DefaultSpdySynReplyFrame(streamId);
spdySynReplyFrame.setLast(!chunked && !httpResponse.getContent().readable());
// Unfold the first line of the response into name/value pairs
SpdyHeaders.setStatus(spdyVersion, spdySynReplyFrame, httpResponse.getStatus());
SpdyHeaders.setVersion(spdyVersion, spdySynReplyFrame, httpResponse.getProtocolVersion());
// Transfer the remaining HTTP headers
for (Map.Entry<String, String> entry: httpResponse.getHeaders()) {
spdySynReplyFrame.addHeader(entry.getKey(), entry.getValue());
}
return spdySynReplyFrame;
}
private SpdyDataFrame[] createSpdyDataFrames(int streamId, ChannelBuffer content) {
int readableBytes = content.readableBytes();
int count = readableBytes / SPDY_MAX_LENGTH;
if (readableBytes % SPDY_MAX_LENGTH > 0) {
count++;
}
SpdyDataFrame[] spdyDataFrames = new SpdyDataFrame[count];
for (int i = 0; i < count; i ++) {
SpdyDataFrame spdyDataFrame = new DefaultSpdyDataFrame(streamId);
int dataSize = Math.min(content.readableBytes(), SPDY_MAX_LENGTH);
spdyDataFrame.setData(content.readSlice(dataSize));
spdyDataFrames[i] = spdyDataFrame;
}
return spdyDataFrames;
}
}