python reflection during runtime

Using Python reflection feature to discover properties and methods of an class

class Employee:

    name: str

    id: int

    def __init__(self, ename:str, eid:int):

     self.name = ename

     self.id = eid

    def hello(_self):

     print("emplyoee")

    @property

    def email(self):

     return "kepung@gmail.com"

e = Employee("Alice", 2)

List all methods and properties 

print(dir(e))

Outputs 

['__annotations__', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getstate__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'email', 'hello', 'id', 'name']

Specific method using hasattr 

 

# check if it has attribute

print(hasattr(e, "hello")) # return True

print(hasattr(e, "name")) # return True

print(hasattr(e, "hello_fake")) # return false

Get actual method or property using getattr 

# using getattr to get actual method

hello_method = getattr(e, "hello")

if hello_method != None:

   hello_method()

else:

   print("method does not exist")

# output employee as it is being run

# Get all methods

methods = inspect.getmembers(e, predicate=inspect.ismethod)

for m in methods:

    print(m)

# Get all properties

properties = [name for name, value in inspect.getmembers(type(e))

              if isinstance(value, property)]

print("Properties:", properties)