event_hierarchy_logger.py

def example():
    import sys
    from twisted.python import log
    log.startLogging(sys.stdout)

    logger = EventHierarchyLogger("myapp", log)
    logger.msg("startup")
    # in another module...
    logger = logger.specialize("rpc")
    logger.msg("got-frag", fragger="dreid", fragee="radix")


# This implementation sucks for a couple of reasons; I think the interface is more important.
class EventHierarchyLogger(object):
    def __init__(self, event_base, logger):
        self.event_base = event_base
        self.logger = logger

    def msg(self, event, *args, **kwargs):
        event = '.'.join([self.event_base, event])
        self.logger.msg(event, *args, **kwargs)

    def err(self, event, *args, **kwargs):
        event = '.'.join([self.event_base, event])
        self.logger.err(self.event_base + event, *args, **kwargs)
 
    def specialize(self, event_segment):
        new_event_base = '.'.join([self.event_base, event_segment])
        return self.__class__(new_event_base, self)
 
 
if __name__ == '__main__':
    example()