/**
* Provides translation between HTTP/2 and HTTP header objects while ensuring the stream is in a
* valid state for additional headers.
*
* @param ctx The context for which this message has been received. Used to send informational
* header if detected.
* @param streamId The stream id the {@code headers} apply to
* @param headers The headers to process
* @param endOfStream {@code true} if the {@code streamId} has received the end of stream flag
* @param allowAppend
* <ul>
* <li>{@code true} if headers will be appended if the stream already exists.
* <li>if {@code false} and the stream already exists this method returns {@code null}.
* </ul>
*
* @param appendToTrailer
* <ul>
* <li>{@code true} if a message {@code streamId} already exists then the headers should be
* added to the trailing headers.
* <li>{@code false} then appends will be done to the initial headers.
* </ul>
*
* @return The object used to track the stream corresponding to {@code streamId}. {@code null} if
* {@code allowAppend} is {@code false} and the stream already exists.
* @throws Http2Exception If the stream id is not in the correct state to process the headers
* request
*/
protected FullHttpMessage processHeadersBegin(
ChannelHandlerContext ctx,
int streamId,
Http2Headers headers,
boolean endOfStream,
boolean allowAppend,
boolean appendToTrailer)
throws Http2Exception {
FullHttpMessage msg = messageMap.get(streamId);
if (msg == null) {
msg = newMessage(streamId, headers, validateHttpHeaders);
} else if (allowAppend) {
try {
HttpConversionUtil.addHttp2ToHttpHeaders(streamId, headers, msg, appendToTrailer);
} catch (Http2Exception e) {
removeMessage(streamId);
throw e;
}
} else {
msg = null;
}
if (sendDetector.mustSendImmediately(msg)) {
// Copy the message (if necessary) before sending. The content is not expected to be copied
// (or used) in
// this operation but just in case it is used do the copy before sending and the resource may
// be released
final FullHttpMessage copy = endOfStream ? null : sendDetector.copyIfNeeded(msg);
fireChannelRead(ctx, msg, streamId);
return copy;
}
return msg;
}
/**
* Create a new {@link FullHttpMessage} based upon the current connection parameters
*
* @param streamId The stream id to create a message for
* @param headers The headers associated with {@code streamId}
* @param validateHttpHeaders
* <ul>
* <li>{@code true} to validate HTTP headers in the http-codec
* <li>{@code false} not to validate HTTP headers in the http-codec
* </ul>
*
* @throws Http2Exception
*/
protected FullHttpMessage newMessage(
int streamId, Http2Headers headers, boolean validateHttpHeaders) throws Http2Exception {
return connection.isServer()
? HttpConversionUtil.toHttpRequest(streamId, headers, validateHttpHeaders)
: HttpConversionUtil.toHttpResponse(streamId, headers, validateHttpHeaders);
}