On our default setup, we use Apache as proxy and load balancer for our applications. This usually works, but caused problems with Thumbor.
With our configuration we add the complete URL including the protocol to the path for tumbor. But this URL is modified on its way to thumbor where the URL is broken due to the removal of the double slash in the protocol.
The not working configuration looks like this:
ProxPass / http://localhost:8888/
ProxPassReverse / http://localhost:8888/
Original URL example: https://thumbor-host/KEY/265x265/smart/https://example.net/image.jpg
The following URL is received by thumbor: /KEY/265x265/smart/https:/example.net/image.jpg
To ensure the protocol double slash is not remove, we applied a workaround configuration:
RewriteEngine on
RewriteCond "%{THE_REQUEST}" "^[A-Z]+\ /([^?\ ]+)/?"
RewriteRule "^/(.*)" "http://localhost:8888/%1" [P,NE]