This stream inflater can inflate incoming header block in streaming
fashion. Currently, we buffer up single name/value pair, but we chose
far more smaller buffer size than HTTP/2 frame size.
Remove the check to see that stream exists at the time when submitting
DATA, PRIORITY and WINDOW_UPDATE. We will do this check when we actually
serialize and send them off to the network (or application provided
buffer).
nghttp2 library itself now accept octet header/value pairs,
completely not restricted by HTTP/1 header name/value rule.
The applications may impose restriction about them using
validators.
Now, in nghttp2_on_frame_recv_callback, nva and nvlen in
HEADERS and PUSH_PROMISE frames are always NULL and 0 respectively.
The header name/value pairs are emitted successive
nghttp2_on_header_callback functions. The end of header fields are
signaled with nghttp2_on_end_headers_callback function.
Since NGHTTP2_ERR_PAUSE for nghttp2_on_frame_recv_callback is
introduced to handle header block, it is now deprecated.
Instead, nghttp2_on_header_callback can be paused using
NGHTTP2_ERR_PAUSE.
We tried several times about this subject, but for the current
HTTP/2.0 priority scheme, we think it is best to serve the highest
priroty streams first (interleaving streams if there are several
higest ones). There are an issue when aggregating several frontend
connections to one connection in backend, but it is HTTP/2.0
spec issue, rather than implementation.
The specification now says that index to the header table entry is
1-based. Since 0-based index is very handy to access arrays, we
internally uses 0-based index. We just convert it to 1-based when
we emit to the block and convert 1-based to 0-based on decoding.
Remove sorting headers from library code. The application must sort
them if necessary. nghttpx and nghttpd do the sorting of the headers
in stable way if names are equal.
nghttp2_session_client_new2 and nghttp2_session_server_new2 take
additional parameters which specifies session options.
nghttp2_set_option is somewhat crumsy because of type checking.
Now we use nghttp2_opt_set, which specifies individual options with
types. We changed the value of nghttp2_opt, so this change will
require re-compile.
It is not clear that SETTINGS_ENABLE_PUSH = 0 disallows HEADERS
to the reserved streams. For now, we just check the reception
and transmission of PUSH_PROMISE against SETTINGS_ENABLE_PUSH.