Set Apache headers conditionally

Question

I\'m working with an apache server, and I\'d like to add headers conditionally.

If the URI matches a certain regex, I\'d like to add the header Access-Control-

Answer 1

This should also work (mod_rewrite is required):

RewriteRule ^/en/foo.*$ - [ENV=SET_ACAO:true]
Header set "Access-Control-Allow-Origin" "*" env=SET_ACAO

where ^/en/foo.*$ a regex which is matched against request URL

Answer 2

SetEnvIf Request_URI somepartofurl SIGN
Header always add "Access-Control-Allow-Origin" "*" env=SIGN

but this works only if located in the configuration. Placing it into .htaccess won't help.