skynet-webportal/docker/nginx/conf.d/include/proxy-cache-downloads

set $nocache 0; # internal variable for bypassing the cache, nginx expects 0/1 for boolean
proxy_cache skynet; # cache name
slice 1m;
proxy_http_version 1.1; # upgrade if necessary because 1.0 does not support byte-range requests
proxy_set_header Range $slice_range; # pass slice range to proxy
proxy_cache_key $uri$arg_format$arg_attachment$slice_range; # use just the uri path, format and attachment args and slice range
proxy_cache_min_uses 3; # cache responses after 3 requests of the same file
proxy_cache_valid 200 206 24h; # cache 200 and 206 responses for 24 hours
proxy_cache_lock on; # queue cache requests for the same resource until it is fully cached
proxy_cache_bypass $nocache $cookie_nocache $arg_nocache; # add cache bypass option
add_header X-Proxy-Cache $upstream_cache_status; # add response header to indicate cache hits and misses