Is there a simple example of how to read a cookie, or some other header value, like "Host" from an ngx_http_request_t ?
I see $variables discussed, but I'm not sure how to retrieve them.

I am guessing it has something to do with ngx_http_script_compile/run, but I don't fully understand the concept.
Those functions seem to rely on a config file, but what if I'm not interested in configuring the variable, I just wish to
retrieve Host or a specific Cookie from each request.

Also, at which stage in an upstream module process is the http request filled?
Are they available in both init_<module>_peer and get_<module>_peer?

Thanks,

Rick