403         """register a function to be called every `interval` seconds.

   403         """register a function to be called every `interval` seconds.

   404 

   404 

   405         looping tasks can only be registered during repository initialization,

   405         looping tasks can only be registered during repository initialization,

   406         once done this method will fail.

   406         once done this method will fail.

   407         """

   407         """

   408         assert self._scheduler is not None, \

   410         assert self._scheduler is not None, \

   409             "This Repository is not intended to be used as a server"

   411             "This Repository is not intended to be used as a server"

   410         event = utils.schedule_periodic_task(

   412         event = utils.schedule_periodic_task(

   411             self._scheduler, interval, func, *args)

   413             self._scheduler, interval, func, *args)

   412         self.info('scheduled periodic task %s (interval: %.2fs)',

   414         self.info('scheduled periodic task %s (interval: %.2fs)',