Plugin Manager

main.py

from plugin_manager import PluginManager

app = App()
app.plugin_manager = PluginManager()
app.plugin_manager.initialize_plugins()

plugin_manager.py

from os import path
from glob import iglob
import logging

class PluginManager(object):
	PLUGINS_DIR = path.abspath(path.dirname(__file__))
	PLUGINS = []

	def initialize_plugins(self):
		sys.path += PLUGINS_DIR
		for fpath in iglob(path.join(PLUGINS_DIR, "*")):
			if path.isfile(fpath):
				if !path.endswith(".py"): continue
				module_name = path.basename(fpath)[:-3]
			else:
				module_name = path.basename(fpath)
			
			mod = __import__(module_name, {}, [], fromlist=[])

			# Assume that the module has a class called 'Plugin'
			# And it has a initializer that takes the plugin_manager as a parameter
			# *convention over configuration*
			# 
			try:
				PLUGINS.append(mod.Plugin(manager))
			except AttributeError:
				logging.error("Plugin not found")