Dynamic files

How do you serve a 'dynamic' file where the filename 
is not known at application start? I have tried 

class MainDirectory(Directory):
   _q_exports = ["", ..... ]

   def _q_index(self):
       if not hasattr(self, str("dynamicfiles")):
          self.dynamicfiles = []
	  # Entries are of the form (urlname, fullpathfilename)
	  # Deletion of entries done by other routines

   def _q_lookup [html] (self, component):
        print "@@@ component = ", str(component)

        for (urlname, filename)  in self.dynamicfiles:
	    print "@@@ filename = ", filename
	    if str(component) == urlname:
	       return StaticFile(filename)()
	       
    def dynamicfile(self, urlname, fullpathfilename):
        print "@@@ appending dynamic file"
	if not hasattr(self, str("dynamicfiles")):
	   self.dynamicfiles = []
        self.dynamicfiles.append((urlname, fullpathfilename))
	print "@@@ redirecting ", str(get_path(1)) + urlname
	redirect(str(get_path(1)) + str("/") + urlname)

This only handle urlname  without a "/". One can write _q_traverse()
for handling this case.  The urlname is mapped to the fullpathfilename.
I don't know if the code is reliable.

Ernie