Hi all!
I'm writing a parser for an internal xml-based metadata format in python. I need to provide different classes for handling different tags. There will be a need for a rather big collection of handlers, so I've envisioned it as a simple plugin system. What I want to do is simply load every class in a package, and register it with my parser.
My current attempt looks like this:
(Handlers is the package containing the handlers, each handler has a static member tags, which is a tuple of strings)
class MetadataParser:
def __init__(self):
#...
self.handlers={}
self.currentHandler=None
for handler in dir(Handlers): # Make a list of all symbols exported by Handlers
if handler[-7:] == 'Handler': # and for each of those ending in "Handler"
handlerMod=my_import('MetadataLoader.Handlers.' + handler)
self.registerHandler(handlerMod, handlerMod.tags) # register them for their tags
# ...
def registerHandler(self, handler, tags):
""" Register a handler class for each xml tag in a given list of tags """
if not isSequenceType(tags):
tags=(tags,) # Sanity check, make sure the tag-list is indeed a list
for tag in tags:
self.handlers[tag]=handler
However, this does not work. I get the error AttributeError: 'module' object has no attribute 'tags'
What am I doing wrong?