Input filters in Nginx?

[awagner]

Hi all. I did some search on the web and the archives here and did not find
an conclusive answer to this question. 

Apache has both input a filters (work on the request before content
generation) and output filters (work on generated content). As I am
exploring the possibility to port some Apache modules that transform data in
both directions in a proxy-setup to Nginx, I am wondering whether Nginx has
input filters as well. What I have read about Nginx modules seem to indicate
that it does not. Is that correct?

I am aware that I could hack something into the proxy module, but I would
like to avoid that approach.

Thanks for any insights or pointers.

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,286038,286038#msg-286038