Iterate over object attributes in python
attributes, iteration, oop, python
Solution
Assuming you have a class such as
>>> class Cls(object):
... foo = 1
... bar = 'hello'
... def func(self):
... return 'call me'
...
>>> obj = Cls()
calling `dir` on the object gives you back all the attributes of that object, including python special attributes. Although some object attributes are callable, such as methods.
>>> dir(obj)
['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'bar', 'foo', 'func']
You can always filter out the special methods by using a list comprehension.
>>> [a for a in dir(obj) if not a.startswith('__')]
['bar', 'foo', 'func']
or if you prefer map/filters.
>>> filter(lambda a: not a.startswith('__'), dir(obj))
['bar', 'foo', 'func']
If you want to filter out the methods, you can use the builtin `callable` as a check.
>>> [a for a in dir(obj) if not a.startswith('__') and not callable(getattr(obj, a))]
['bar', 'foo']
You could also inspect the difference between your class and its instance object using.
>>> set(dir(Cls)) - set(dir(object))
set(['__module__', 'bar', 'func', '__dict__', 'foo', '__weakref__'])
Problem
I have a python object with several attributes and methods. I want to iterate over object attributes. ``` class my_python_obj(object): attr1='a' attr2='b' attr3='c' def method1(self, etc, etc): #Statements ``` I want to generate a dictionary containing all of the objects attributes and their current values, but I want to do it in a dynamic way (so if later I add another attribute I don't have to remember to update my function as well). In php variables can be used as keys, but objects in python are unsuscriptable and if I use the dot notation for this it creates a new attribute with the name of my var, which is not my intent. Just to make things clearer: ``` def to_dict(self): '''this is what I already have''' d={} d["attr1"]= self.attr1 d["attr2"]= self.attr2 d["attr3"]= self.attr3 return d ``` · ``` def to_dict(self): '''this is what I want to do''' d={} for v in my_python_obj.attributes: d[v] = self.v return d ``` Update: With attributes I mean only the variables of this object, not the methods.