Any method for NGINX (as a web-server) to skip metadata and serve content from cached file?

[rnmx18]

Hi Lucas,

As long as the cached files (with the metadata at the beginning) reside in
the directory specified with the proxy_cache_path directive, they are fine.
The NGINX-proxy, which added them there in the first place, can serve the
content correctly, after skipping the right amount of metadata bytes.

In my case, I have a background application, which might copy the cached
file to an alternate location. For example, a file movies/welcome.mp4 may be
originally cached by NGINX-proxyon /disk1/cache as
/disk1/cache/movies/welcome.mp4  (For the moment, let us forget the
md5-based cache path for simplicity).  In my use-case, the file may either
stay there itself, or sometimes, my application may copy it to another
location  - say /disk2/cache/movies/welcome.mp4 or say,
/disk3/cache/movies/welcome.mp4, say for some kind of disk usage balancing..
The application exposes /disk1/pubroot/cache/movies/welcome.mp4 as the
published location.

In this model, only the originally cached file at /disk1/cache can be served
properly by the NGINX-proxy. 

The files in any of the other locations cannot be served by NGINX properly.
It cannot serve as a server, as the copied file contains metadata. Even if I
have other proxy-cache-paths defined for the alternate locations
(/disk2/cache or /disk3/cache), the NGINX-proxy also cannot serve them as
the corresponding in-memory metadata will not have the entries for these
files. The files in those paths, would have been physically copied "under
the hood" by another process, and not NGINX.

Thanks
Rajesh

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,276612,276621#msg-276621