[06:17:21] <ori>	 kostajh: I'd log it at the web server level. Apache has '%B' (https://httpd.apache.org/docs/2.4/mod/mod_log_config.html#formats), nginx has $bytes_sent (https://nginx.org/en/docs/http/ngx_http_log_module.html#log_format), etc.
[14:48:21] <Krinkle>	 We disable gzip on app servers afaik (edge only) and URLs are localised. But some kind of mtail solution based on server logs with a URL filter could work and send stuff to Prometheus.