Getting Attributes of a Class

Getting attributes of a class

Try the inspect module. getmembers and the various tests should be helpful.

EDIT:

For example,

class MyClass(object):
    a = '12'
    b = '34'
    def myfunc(self):
        return self.a

>>> import inspect
>>> inspect.getmembers(MyClass, lambda a:not(inspect.isroutine(a)))
[('__class__', type),
 ('__dict__',
  <dictproxy {'__dict__': <attribute '__dict__' of 'MyClass' objects>,
   '__doc__': None,
   '__module__': '__main__',
   '__weakref__': <attribute '__weakref__' of 'MyClass' objects>,
   'a': '34',
   'b': '12',
   'myfunc': <function __main__.myfunc>}>),
 ('__doc__', None),
 ('__module__', '__main__'),
 ('__weakref__', <attribute '__weakref__' of 'MyClass' objects>),
 ('a', '34'),
 ('b', '12')]

Now, the special methods and attributes get on my nerves- those can be dealt with in a number of ways, the easiest of which is just to filter based on name.

>>> attributes = inspect.getmembers(MyClass, lambda a:not(inspect.isroutine(a)))
>>> [a for a in attributes if not(a[0].startswith('__') and a[0].endswith('__'))]
[('a', '34'), ('b', '12')]

...and the more complicated of which can include special attribute name checks or even metaclasses ;)

Get all attributes of a class in Python

Use vars

for property, value in vars(your_class).iteritems():
    print(property, ":", value)

Can I get all attributes that were defined in the __init__ method of a class?

You can do this by looking at the __dict__ attribute or using the vars function like so:

class A:
    def __init__(self):
        self.a = "a"
        self.b = "b"

print(A().__dict__)  # prints {'a': 'a', 'b': 'b'}
print(vars(A()))     # also prints {'a': 'a', 'b': 'b'}

Get the list of 'property' class attributes of a class in python

propertys are defined on the class, if you try to access them via an instance, their __get__ is called. So make it a class method instead:

    @classmethod
    def get_props(cls):
        return [x for x in dir(cls)
                if isinstance( getattr(cls, x), property) ]

Get all object attributes in Python?

Use the built-in function dir().

How to get types of attributes of a class object without initializing it in python

Without initialization local params like param0 and param2 are not evaluated, so Python interpreter has no information about their existence or type.

The only possibility you have is to collect arguments of __init__ method. Using your example structure:

import inspect

params = []
for parent in ExampleParams.mro()[::-1]:
    parent_init = inspect.getfullargspec(parent.__init__)
    # parent_init.annotations contains annotations if specified in method signature
    for param in parent_init.args:
        if param == 'self':
            continue
        params.append(param)

params = ['param1'] in your case.

Print all properties of a Python Class

In this simple case you can use vars():

an = Animal()
attrs = vars(an)
# {'kids': 0, 'name': 'Dog', 'color': 'Spotted', 'age': 10, 'legs': 2, 'smell': 'Alot'}
# now dump this in some way or another
print(', '.join("%s: %s" % item for item in attrs.items()))

If you want to store Python objects on the disk you should look at shelve — Python object persistence.

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