Check URL and redirect based on URL string

I need to have the BigIP read the URI and look for a "?".

 

 

If it contains the ?, then append with "dom=sp" and redirect to a VIP.

 

 

If it does NOT contain a ?, then append the url with ?dom="sp"

 

 

I suppose i need to know if this is even feasible at this point. I have so far not been successful.

 

 

So far the only thing I have is

 

 

rule my_rule {

 

if (http_uri contains "?") {

 

redirect to "http://%h/%udom=sp"

 

else

 

redirect to "http://%h/%u?dom=sp"