We released nghttp2 v1.13.0.

This release fixes several build issues, and add a new library feature. nghttpx session affinity feature has been improved.

We can now cancel non-DATA frame transmission from nghttp2_before_frame_send_callback by returning NGHTTP2_ERR_CANCEL from there. This could be useful for some cases where we know the transmission of a frame should be avoided. The upcoming use case is cache digest. After queuing PUSH_PROMISE frame, but before actually sending the frame, we may know client has the fresh copy of the resources by CACHE_DIGEST frame. In that case, it is desirable to cancel transmission of PUSH_PROMISE frame. nghttp2_on_frame_not_send_callback is invoked if frame transmission is canceled as usual.

We fixed number of warnings with Sphinx 1.4.0.

nghttpx’s session affinity using client IP is improved by using the similar hashing technique described in https://github.com/RJ/ketama