Rewrite to append to query string

Question

I don't understand why I always have such a massive problem with rewrite rules, but I simply want to append to the query string if it exists and add a ? if it does not. I actually don't care if the URL is changed in the browser or not -- it just has to load the correct target page.

RewriteRule /cia16(.*)\?(.*) /cia$1?$2&CIA=16
RewriteRule /cia16(.*) /cia/$1?CIA=16

If I go to /cia16/steps.php?page=1 it actually gets rewritten to /cia/steps.php?CIA=16 -- that is it seems accept the query string part is not even considered part of the URL for the purposes of the rewrite.

What do I have to do to get the rewrite to work properly with an existing query string?

Answer 1

You can't match against the query string within a RewriteRule, you need to match against the %{QUERY_STRING} variable in a RewriteCond. However, if you want to just append the query string, you can just use the QSA flag:

RewriteRule /cia16(.*) /cia/$1?CIA=16 [QSA]

The URI: /cia16/steps.php?page=1 would get rewritten to /cia/steps.php?CIA=16&page=1. If for some reason, you need the page=1 before the CIA=16, then you can do something like this:

RewriteRule /cia16(.*) /cia/$1?%{QUERY_STRING}&CIA=16