Question

How do I get the attribute names and values of an object? I’m attempting to cast it to a dictionary so that I can easily JSON serialize the object.

Code:

class User:
    ...
    def to_dict( self ):
        dict = {}
        for key, value in filter( lambda aname: not aname.startswith('_'), dir(self) ):
            dict[key] = value
    return dict

Error:

too many values to unpack

Use:

user = User({
    's_email': '[e-mail]',
    's_password': 'password',
})
user.to_dict()
# JSON Serialize

Answer 1

Use self.__dict__. It is a dictionary representing the namespace of the object.

class User:
    ...
    def to_dict(self):
        return dict(
            [(k, v) for k, v in self.__dict__.iteritems() if not k.startswith('_')]
        )

Note that given your code snippet, the dict returned by .to_dict() would contain the key 'to_dict' as the function does not start with an underscore. Probably a simple mistake in your post.

If the list of attributes that you want to include in the returned dict is small (and doesn’t change much), I suggest being explicit about it and listing them

class User(object):
    data_attributes = ('s_email', 's_password')
    def to_dict(self):
        return dict([(attr, getattr(self, attr) for attr in self.data_attributes])