Redirecting with dynamic URI content

I am trying to find an example of a redirection that takes into account the node passing dynamic variables back to the client upon initial request. If I use the [HTTP::uri] param in the normal redirect from 80 to 443, it truncated the dynamic variables. Is there a provision for telling the redirect to add space to the redirect?

For example

if { [HTTP::uri] starts_with "/uri1/" } {

HTTP::redirect "https://[[HTTP::host][HTTP::uri] 20]"

I know that isnt correct but you get the idea. adding the next 20 characters at the end of the uri that was used as the trigger.

I hope that makes sense.

TIA