Delay decorator action until class instantiation to allow access to class variable.

gistfile1.py

class Router(object):
    def __init__(self):
        self.methods = {}
    def route(self, url):
        def decorator(wrapped):
            wrapped.__route_info__ = (self, url)
            return wrapped
        return decorator
    def register(self, url, method):
        self.methods[url] = method
    def dispatch(self, url):
        return self.methods[url]()

router = Router()

class ApplicationMetaClass(type):
    def __new__(cls, name, bases, attrs):
        
        instance = super(ApplicationMetaClass, cls).__new__(cls, name, bases, attrs)
        
        for attrname, attrvalue in attrs.iteritems():
            info = getattr(attrvalue, '__route_info__', None)
            if info is not None:
                mount_point = attrs.get('__mount_point__', ApplicationRoot.__mount_point__)
                info[0].register(mount_point+info[1], attrvalue.__get__(instance, cls))
                
        return instance

class ApplicationRoot(object):
    __metaclass__ = ApplicationMetaClass
    __mount_point__ = ''

class Application1(ApplicationRoot):
    
    @router.route('/')
    def root(self):
        return self.__mount_point__, 'root'
        
    @router.route('/suburl')
    def suburl(self):
        return self.__mount_point__, 'suburl'
        
class Application2(ApplicationRoot):

    __mount_point__ = '/app1'
    
    @router.route('/')
    def root(self):
        return self.__mount_point__, 'root'
        
    @router.route('/suburl')
    def suburl(self):
        return self.__mount_point__, 'suburl'
        
app1 = Application1()
app2 = Application2()

print router.methods
print
print router.dispatch('/')
print
print router.dispatch('/suburl')
print
print router.dispatch('/app1/')
print
print router.dispatch('/app1/suburl')