That's interesting, Pierre, I hadn't really read the RFC carefully, to realize that many of the "missing" variables from Apache are HTTP headers, and that section 4.1.18 tell how to convert HTTP headers to meta variables.

The code in server.py 3.6 (Sorry, I should check the master branch) picks specific HTTP_ headers to include, rather than including them all per the rules. Doing the latter would go a long way toward being more compatible with Apache. I don't know if Rémi got his NGINX list from source code (looks like it) and if maybe NGINX also defines meta variables from the HTTP_ headers, that are not listed in the header file he seems to be quoting.

Unless the code has already been improved for Python 3.7, I think there is still some work to do to make server.py conform even to the RFC, if not be compatible with Apache.