[PATCH] HTTP/2: add debug logging of control frames

[Piotr Sikora]

Hey Valentin,

> You can always find these values in configuration, and I can't remember a case where
> I've ever needed them.  On the contrary, there's always a problem with the huge size
> of typical http/2 debug log.  So it's not a good idea to add something just because
> we can.

As someone who spent the last few days debugging HTTP/2
interoperability issues, looking at those debug logs, I strongly
disagree.

Also, NGINX's HTTP/2 debug log is really nice (other than the lack of
"recv" prefix [1]) and can be used as a transcript of HTTP/2 exchange,
which can be shared with people that don't use NGINX, in which case
having SETTINGS values there is critical.

Actually, I have local patch that adds even more debugging for
SETTINGS frame (I'll squash it into this one and send to the mailing
list shortly).

[1] btw: Would you accept patch that adds "recv" prefix to all
received frames? This would allow for easy "http2 send|http2 recv"
grep for HTTP/2 transcript, and would align frame recv/send messages.

Best regards,
Piotr Sikora