Remove parentheses from the URLs query string in rewrite rule - .htaccess

Question

I would like to clean up the URL's by removing parentheses from all query strings.
I tried the following code, but couldn't get it to work.
RewriteCond %{REQUEST_URI} [\(\)]+
RewriteRule ^(.*)[\(]+([^\)]*)[\)]+(.*)$ /$1$2$3 [R=301,L]
Here's an example of a URL:
http://www.example.com/blog/abc-post/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+blogname+(Blog+Name+New+York)

Answer 1

In order to match the query string you need to check the QUERY_STRING server variable in a RewriteCond directive.
Here are some ways of doing this:
1. Any number of parentheses - multiple redirects
For example, to remove any number of opening/closing parentheses in the query string part of the URL:
RewriteCond %{QUERY_STRING} (.*)[()]+(.*)
RewriteRule (.*) /$1?%1%2 [R,NE,L]
The NE flag is required in your example to avoid the %-encoded character (ie. %3A) being doubly encoded.
This will, however, result in multiple redirects, depending on the number of "groups" of parentheses. In your example, this will result in two redirects, because there a two "groups" of parentheses (a single parenthesis in each "group").
2. Any number of parentheses pairs - multiple (but fewer) redirects
If the parenthesis are always in matching pairs, then you can specifically check for the opening/closing parenthesis and potentially reduce the number of redirects.
RewriteCond %{QUERY_STRING} (.*)\((.*)\)(.*)
RewriteRule (.*) /$1?%1%2%3 [R,NE,L]
In your example, this results in a single redirect because there is just a single pair of parentheses. But /abc?foo=(bar)&one=(two) would result in two redirects.
3. Any number of parentheses - single redirect
This method performs multiple internal rewrites to remove the parentheses, followed by a single redirect once all the parentheses have been replaced:
# Remove parentheses from query string
RewriteCond %{QUERY_STRING} (.*)[()]+(.*)
RewriteRule (.*) /$1?%1%2 [E=REPLACED_PARENS:1,NE,L]
# Redirect to "clean" URL
RewriteCond %{ENV:REDIRECT_REPLACED_PARENS} 1
RewriteCond %{THE_REQUEST} ^GET\ /(.*)\?
RewriteRule ^ /%1 [R,NE,L]
The first rule internally rewrites the request and sets an environment variable if a replacement is required.
The second rule checks for this environment variable (note that REPLACED_PARENS becomes REDIRECT_REPLACED_PARENS after the first rewrite) and ultimately redirects to the cleaned URL. The URL-path is grabbed from the initial request (contained in the THE_REQUEST server variable) to avoid inadvertantly redirecting to the directory index (eg. index.php) when a bare directory is requested (or front-controller is used).