netty5/codec-http2/src/main/java/io/netty/handler/codec/http2/Http2FrameCodecBuilder.java
Scott Mitchell b3dba317d7
HTTP/2 to support asynchronous SETTINGS ACK (#9069)
Motivation:
The HTTP/2 codec will synchronously respond to a SETTINGS frame with a SETTINGS
ACK before the application sees the SETTINGS frame. The application may need to
adjust its state depending upon what is in the SETTINGS frame before applying
the remote settings and responding with an ACK (e.g. to adjust for max
concurrent streams). In order to accomplish this the HTTP/2 codec should allow
for the application to opt-in to sending the SETTINGS ACK.

Modifications:
- DefaultHttp2ConnectionDecoder should support a mode where SETTINGS frames can
  be queued instead of immediately applying and ACKing.
- DefaultHttp2ConnectionEncoder should attempt to poll from the queue (if it
  exists) to apply the earliest received but not yet ACKed SETTINGS frame.
- AbstractHttp2ConnectionHandlerBuilder (and sub classes) should support a new
  option to enable the application to opt-in to managing SETTINGS ACK.

Result:
HTTP/2 allows for asynchronous SETTINGS ACK managed by the application.
2019-04-25 15:52:05 -07:00

179 lines
5.9 KiB
Java

/*
* Copyright 2017 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.http2;
import io.netty.util.internal.UnstableApi;
import static io.netty.util.internal.ObjectUtil.checkNotNull;
/**
* Builder for the {@link Http2FrameCodec}.
*/
@UnstableApi
public class Http2FrameCodecBuilder extends
AbstractHttp2ConnectionHandlerBuilder<Http2FrameCodec, Http2FrameCodecBuilder> {
private Http2FrameWriter frameWriter;
Http2FrameCodecBuilder(boolean server) {
server(server);
}
/**
* Creates a builder for a HTTP/2 client.
*/
public static Http2FrameCodecBuilder forClient() {
return new Http2FrameCodecBuilder(false);
}
/**
* Creates a builder for a HTTP/2 server.
*/
public static Http2FrameCodecBuilder forServer() {
return new Http2FrameCodecBuilder(true);
}
// For testing only.
Http2FrameCodecBuilder frameWriter(Http2FrameWriter frameWriter) {
this.frameWriter = checkNotNull(frameWriter, "frameWriter");
return this;
}
@Override
public Http2Settings initialSettings() {
return super.initialSettings();
}
@Override
public Http2FrameCodecBuilder initialSettings(Http2Settings settings) {
return super.initialSettings(settings);
}
@Override
public long gracefulShutdownTimeoutMillis() {
return super.gracefulShutdownTimeoutMillis();
}
@Override
public Http2FrameCodecBuilder gracefulShutdownTimeoutMillis(long gracefulShutdownTimeoutMillis) {
return super.gracefulShutdownTimeoutMillis(gracefulShutdownTimeoutMillis);
}
@Override
public boolean isServer() {
return super.isServer();
}
@Override
public int maxReservedStreams() {
return super.maxReservedStreams();
}
@Override
public Http2FrameCodecBuilder maxReservedStreams(int maxReservedStreams) {
return super.maxReservedStreams(maxReservedStreams);
}
@Override
public boolean isValidateHeaders() {
return super.isValidateHeaders();
}
@Override
public Http2FrameCodecBuilder validateHeaders(boolean validateHeaders) {
return super.validateHeaders(validateHeaders);
}
@Override
public Http2FrameLogger frameLogger() {
return super.frameLogger();
}
@Override
public Http2FrameCodecBuilder frameLogger(Http2FrameLogger frameLogger) {
return super.frameLogger(frameLogger);
}
@Override
public boolean encoderEnforceMaxConcurrentStreams() {
return super.encoderEnforceMaxConcurrentStreams();
}
@Override
public Http2FrameCodecBuilder encoderEnforceMaxConcurrentStreams(boolean encoderEnforceMaxConcurrentStreams) {
return super.encoderEnforceMaxConcurrentStreams(encoderEnforceMaxConcurrentStreams);
}
@Override
public Http2HeadersEncoder.SensitivityDetector headerSensitivityDetector() {
return super.headerSensitivityDetector();
}
@Override
public Http2FrameCodecBuilder headerSensitivityDetector(
Http2HeadersEncoder.SensitivityDetector headerSensitivityDetector) {
return super.headerSensitivityDetector(headerSensitivityDetector);
}
@Override
public Http2FrameCodecBuilder encoderIgnoreMaxHeaderListSize(boolean ignoreMaxHeaderListSize) {
return super.encoderIgnoreMaxHeaderListSize(ignoreMaxHeaderListSize);
}
@Override
public Http2FrameCodecBuilder initialHuffmanDecodeCapacity(int initialHuffmanDecodeCapacity) {
return super.initialHuffmanDecodeCapacity(initialHuffmanDecodeCapacity);
}
/**
* Build a {@link Http2FrameCodec} object.
*/
@Override
public Http2FrameCodec build() {
Http2FrameWriter frameWriter = this.frameWriter;
if (frameWriter != null) {
// This is to support our tests and will never be executed by the user as frameWriter(...)
// is package-private.
DefaultHttp2Connection connection = new DefaultHttp2Connection(isServer(), maxReservedStreams());
Long maxHeaderListSize = initialSettings().maxHeaderListSize();
Http2FrameReader frameReader = new DefaultHttp2FrameReader(maxHeaderListSize == null ?
new DefaultHttp2HeadersDecoder(true) :
new DefaultHttp2HeadersDecoder(true, maxHeaderListSize));
if (frameLogger() != null) {
frameWriter = new Http2OutboundFrameLogger(frameWriter, frameLogger());
frameReader = new Http2InboundFrameLogger(frameReader, frameLogger());
}
Http2ConnectionEncoder encoder = new DefaultHttp2ConnectionEncoder(connection, frameWriter);
if (encoderEnforceMaxConcurrentStreams()) {
encoder = new StreamBufferingEncoder(encoder);
}
Http2ConnectionDecoder decoder = new DefaultHttp2ConnectionDecoder(connection, encoder, frameReader,
promisedRequestVerifier(), isAutoAckSettingsFrame());
return build(decoder, encoder, initialSettings());
}
return super.build();
}
@Override
protected Http2FrameCodec build(
Http2ConnectionDecoder decoder, Http2ConnectionEncoder encoder, Http2Settings initialSettings) {
return new Http2FrameCodec(encoder, decoder, initialSettings);
}
}