I am using nginx as a reverse proxy for IBM Lotus Domino Web Mail. Since there are some internal only URL in email content, I need http_sub_module to modify(add some prefix ) the URL so that user outside intranet can click the link and access through another portal.

I add

sub_filter aaa bbb; sub_filter_types application/json application/x-javascript; sub_filter_once off;

into the nginx.conf and it does not work.'aaa' is not replaced by 'bbb'

However, if I save the web page as html file or generate some json which contains 'aaa'. It can be replace by 'bbb'.

Therefore, it there any other options besides `Content-Type` can prevent http_sub_module replacing the word?

Sorry for my bad English...