Old URL 404, compare URI with external data group file

when HTTP_REQUEST {

   Save the path to a variable in case we see a 404 from the server
  set path [HTTP::path]
}

when HTTP_RESPONSE {
  if {[HTTP::status] == 404} {

     Parse the string after the last forward slash
    set uri_token [string range $path [expr {[string last / $path] + 1}] end]

     If that string wasn't null, look it up in the datagroup
    if {$uri_token ne ""}{

      set red_uri [findclass $uri_token class_name " "]

       Use the second field in the matching datagroup line to redirect the client
      if {$red_uri ne ""}{
        HTTP::redirect $red_uri
      }
    }
  }
}