.htaccess

# taken from https://www.youtube.com/watch?v=QDK2c7rokOw
<IfModule mod_deflate.c>
  #Insert filter
  SetOutputFilter DEFLATE

  # Netscape 4.x has some problems...
  BrowserMatch ^Moxilla/4 gzip-only-text/html

  # Netscape 4.06-4.08 has some more problems
  BrowserMatch ^Mozilla/4\.0[678] no-gzip

  # MSIE masquerades as Netscape, but it is fine
  # BrowserMatch \bMSIE !no-gzip-only-text/html

  # NOTE: Due to a bug in mod_setenvif up to Apache 2.0.48
  # the above regez won't work. You can use the following workaround
  # to get the desired effect
  BrowserMatch \bMSI[E] !no-gzip !gzip-only-text/html

  # Don't compress images
  SetEnvIfNoCase Request_URI \
  \.(?:gif|jpe?g|png)$ no-gzip dont-vary

  # Maje sure proxies don't deliver the wrong content
  Header append Vary User-Agent env=!dont-vary
</IfModule>

Header add Access-Control-Expose-Headers "Content-Length"