Is there any way to access upstream response from configuration?

[aldem]

Hi,

I am trying to make caching selective based on cookies set by upstream.

Example: worpress sets wordpress_test_cookie for every page, thus preventing
caching of pages unless Set-Cookie headers are ignored. On the other hand,
ignoring Set-Cookie in general is bad idea, as in this case when other
cookies are set (like wordpress_logged_in) the response will be cached as
well - and this is a security (and consistency) disaster.

What I want is to check if specific header or cookie in the *response* is
set and make decision to cache or not based on this information.

Is this possible at all? I couldn't find anything (like variables) that
allows to examine response for this purpose.

PS: I know that there are some "helper" plugins for wordpress, but wordpress
is only one of possible applications, I need a solution that could work
without application support, that is why I am interested in response
examination.

Thank you!

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,250345,250345#msg-250345