A __getattr__ for class methods?

[Michael Spencer]

Dylan Moreland wrote:
> I'm trying to implement a bunch of class methods in an ORM object in
> order to provide functionality similar to Rails' ActiveRecord. This
> means that if I have an SQL table mapped to the class "Person" with
> columns name, city, and email, I can have class methods such as:
> 
>     Person.find_by_name
>     Person.find_by_city_and_name
>     Person.find_by_name_and_city_and_email
> 
> I have a metaclass generating basic properties such as .name and .city,
> but I don't want to generate a class method for every permutation of
> the attributes. I'd like to have something much like __getattr__ for
> instance attributes, so that if a method like
> Person.find_by_city_and_email cannot be found, I can construct a call
> to the basic find method that hides the SQL. Is there any way of doing
> this, ...

Sure, define __getattr__ on the type of the class i.e., the metaclass, just as 
you define it on a class to provide default-attribute-lookup to its instances:

  >>> class A(object):
  ...     class __metaclass__(type):
  ...         def __getattr__(cls, attr):
  ...             return "%s.%s" % (cls.__name__, attr)
  ...
  >>> A.somefunc
  'A.somefunc'
  >>> A.someotherfunc
  'A.someotherfunc'
  >>>

HTH

Michael