/*
* Copyright 2014 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.buffer.ByteBuf;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPromise;
import io.netty.util.internal.UnstableApi;
import java.io.Closeable;
/**
* A writer responsible for marshaling HTTP/2 frames to the channel. All of the write methods in
* this interface write to the context, but DO NOT FLUSH. To perform a flush, you must separately
* call {@link ChannelHandlerContext#flush()}.
*/
@UnstableApi
public interface Http2FrameWriter extends Http2DataWriter, Closeable {
/**
* Configuration specific to {@link Http2FrameWriter}
*/
interface Configuration {
/**
* Get the {@link Http2HeadersEncoder.Configuration} for this {@link Http2FrameWriter}
*/
Http2HeadersEncoder.Configuration headersConfiguration();
/**
* Get the {@link Http2FrameSizePolicy} for this {@link Http2FrameWriter}
*/
Http2FrameSizePolicy frameSizePolicy();
}
/**
* Writes a HEADERS frame to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param streamId the stream for which to send the frame.
* @param headers the headers to be sent.
* @param padding additional bytes that should be added to obscure the true content size. Must be between 0 and
* 256 (inclusive).
* @param endStream indicates if this is the last frame to be sent for the stream.
* @param promise the promise for the write.
* @return the future for the write.
* <a href="https://tools.ietf.org/html/rfc7540#section-10.5.1">Section 10.5.1</a> states the following:
* <pre>
* The header block MUST be processed to ensure a consistent connection state, unless the connection is closed.
* </pre>
* If this call has modified the HPACK header state you <strong>MUST</strong> throw a connection error.
* <p>
* If this call has <strong>NOT</strong> modified the HPACK header state you are free to throw a stream error.
*/
ChannelFuture writeHeaders(ChannelHandlerContext ctx, int streamId, Http2Headers headers,
int padding, boolean endStream, ChannelPromise promise);
/**
* Writes a HEADERS frame with priority specified to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param streamId the stream for which to send the frame.
* @param headers the headers to be sent.
* @param streamDependency the stream on which this stream should depend, or 0 if it should
* depend on the connection.
* @param weight the weight for this stream.
* @param exclusive whether this stream should be the exclusive dependant of its parent.
* @param padding additional bytes that should be added to obscure the true content size. Must be between 0 and
* 256 (inclusive).
* @param endStream indicates if this is the last frame to be sent for the stream.
* @param promise the promise for the write.
* @return the future for the write.
* <a href="https://tools.ietf.org/html/rfc7540#section-10.5.1">Section 10.5.1</a> states the following:
* <pre>
* The header block MUST be processed to ensure a consistent connection state, unless the connection is closed.
* </pre>
* If this call has modified the HPACK header state you <strong>MUST</strong> throw a connection error.
* <p>
* If this call has <strong>NOT</strong> modified the HPACK header state you are free to throw a stream error.
*/
ChannelFuture writeHeaders(ChannelHandlerContext ctx, int streamId, Http2Headers headers,
int streamDependency, short weight, boolean exclusive, int padding, boolean endStream,
ChannelPromise promise);
/**
* Writes a PRIORITY frame to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param streamId the stream for which to send the frame.
* @param streamDependency the stream on which this stream should depend, or 0 if it should
* depend on the connection.
* @param weight the weight for this stream.
* @param exclusive whether this stream should be the exclusive dependant of its parent.
* @param promise the promise for the write.
* @return the future for the write.
*/
ChannelFuture writePriority(ChannelHandlerContext ctx, int streamId, int streamDependency,
short weight, boolean exclusive, ChannelPromise promise);
/**
* Writes a RST_STREAM frame to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param streamId the stream for which to send the frame.
* @param errorCode the error code indicating the nature of the failure.
* @param promise the promise for the write.
* @return the future for the write.
*/
ChannelFuture writeRstStream(ChannelHandlerContext ctx, int streamId, long errorCode,
ChannelPromise promise);
/**
* Writes a SETTINGS frame to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param settings the settings to be sent.
* @param promise the promise for the write.
* @return the future for the write.
*/
ChannelFuture writeSettings(ChannelHandlerContext ctx, Http2Settings settings,
ChannelPromise promise);
/**
* Writes a SETTINGS acknowledgment to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param promise the promise for the write.
* @return the future for the write.
*/
ChannelFuture writeSettingsAck(ChannelHandlerContext ctx, ChannelPromise promise);
/**
* Writes a PING frame to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param ack indicates whether this is an ack of a PING frame previously received from the
* remote endpoint.
* @param data the payload of the frame. This will be released by this method.
* @param promise the promise for the write.
* @return the future for the write.
*/
ChannelFuture writePing(ChannelHandlerContext ctx, boolean ack, ByteBuf data,
ChannelPromise promise);
/**
* Writes a PUSH_PROMISE frame to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param streamId the stream for which to send the frame.
* @param promisedStreamId the ID of the promised stream.
* @param headers the headers to be sent.
* @param padding additional bytes that should be added to obscure the true content size. Must be between 0 and
* 256 (inclusive).
* @param promise the promise for the write.
* @return the future for the write.
* <a href="https://tools.ietf.org/html/rfc7540#section-10.5.1">Section 10.5.1</a> states the following:
* <pre>
* The header block MUST be processed to ensure a consistent connection state, unless the connection is closed.
* </pre>
* If this call has modified the HPACK header state you <strong>MUST</strong> throw a connection error.
* <p>
* If this call has <strong>NOT</strong> modified the HPACK header state you are free to throw a stream error.
*/
ChannelFuture writePushPromise(ChannelHandlerContext ctx, int streamId, int promisedStreamId,
Http2Headers headers, int padding, ChannelPromise promise);
/**
* Writes a GO_AWAY frame to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param lastStreamId the last known stream of this endpoint.
* @param errorCode the error code, if the connection was abnormally terminated.
* @param debugData application-defined debug data. This will be released by this method.
* @param promise the promise for the write.
* @return the future for the write.
*/
ChannelFuture writeGoAway(ChannelHandlerContext ctx, int lastStreamId, long errorCode,
ByteBuf debugData, ChannelPromise promise);
/**
* Writes a WINDOW_UPDATE frame to the remote endpoint.
*
* @param ctx the context to use for writing.
* @param streamId the stream for which to send the frame.
* @param windowSizeIncrement the number of bytes by which the local inbound flow control window
* is increasing.
* @param promise the promise for the write.
* @return the future for the write.
*/
ChannelFuture writeWindowUpdate(ChannelHandlerContext ctx, int streamId,
int windowSizeIncrement, ChannelPromise promise);
/**
* Generic write method for any HTTP/2 frame. This allows writing of non-standard frames.
*
* @param ctx the context to use for writing.
* @param frameType the frame type identifier.
* @param streamId the stream for which to send the frame.
* @param flags the flags to write for this frame.
* @param payload the payload to write for this frame. This will be released by this method.
* @param promise the promise for the write.
* @return the future for the write.
*/
ChannelFuture writeFrame(ChannelHandlerContext ctx, byte frameType, int streamId,
Http2Flags flags, ByteBuf payload, ChannelPromise promise);
/**
* Get the configuration related elements for this {@link Http2FrameWriter}
*/
Configuration configuration();
/**
* Closes this writer and frees any allocated resources.
*/
@Override
void close();
}