Nginx proxy_cache_path

I am trying to set up my Plesk Joomla website to reverse proxy some requests to a application server and would like to implement the cache.

Is it possible to setup up the proxy cache for nginx. The directive proxy_cache_path nneeds to be set at the http context within the configuration file however it seems that Plesk implementation only allows directives and the server context.

if I had this directive to be nginx settings I get Invalid nginx configuration: nginx: [emerg]...

Nginx proxy_cache_path