How can I apply a decorator to an imported function? [duplicate]

Decorators are just syntactic sugar to replace a function object with a decorated version, where decorating is just calling (passing in the original function object). In other words, the syntax: @decorator_expression def function_name(): # function body roughly(*) translates to: def function_name(): # function body function_name = decorator_expression(function_name) In your case, you can apply your decorator … Read more

What is the difference between @staticmethod and @classmethod in Python?

Maybe a bit of example code will help: Notice the difference in the call signatures of foo, class_foo and static_foo: class A(object): def foo(self, x): print(f”executing foo({self}, {x})”) @classmethod def class_foo(cls, x): print(f”executing class_foo({cls}, {x})”) @staticmethod def static_foo(x): print(f”executing static_foo({x})”) a = A() Below is the usual way an object instance calls a method. The … Read more

How can one attach a decorator to a function “after the fact” in python?

You imported sqrt into your module, just apply the decorator there in your own global namespace: sqrt = print_args_decor(sqrt) This sets the name sqrt in your module namespace to the result of the decorator. There is no requirement that sqrt was originally defined in this module. It is up to the decorator to uses the … Read more

@staticmethod vs @classmethod in Python

Maybe a bit of example code will help: Notice the difference in the call signatures of foo, class_foo and static_foo: class A(object): def foo(self, x): print(f”executing foo({self}, {x})”) @classmethod def class_foo(cls, x): print(f”executing class_foo({cls}, {x})”) @staticmethod def static_foo(x): print(f”executing static_foo({x})”) a = A() Below is the usual way an object instance calls a method. The … Read more

React js – What is the difference betwen HOC and decorator

For all practical reasons, decorators and HOC (Higher-Order-Component aka Wrapper) do the same thing. One major difference is that, once you add a decorator, the property/class can only be used in it’s decorated form. HOC pattern leaves higher order as well as the lower order components available for use. For further reading on decorators -> … Read more

Same name functions in same class – is there an elegant way to determine which to call?

Inheritance is probably the best way to do this, but since you asked specifically about decorators, I wanted to show you could do this using decorators. You’ll need to use a dictionary to store your functions by version, and then look up which version to use at runtime. Here’s an example. version_store = {} def … Read more

How to skip a pytest using an external fixture?

It seems py.test doesn’t use the test fixtures when evaluating the expression for skipif. By your example, test_ios is actually successful because it is comparing the function platform found in the module’s namespace to the “ios” string, which evaluates to False hence the test is executed and succeeds. If pytest was inserting the fixture for … Read more

How to add a custom decorator to a FastAPI route?

How can I add any decorators to FastAPI endpoints? As you said, you need to use @functools.wraps(…)–(PyDoc) decorator as, from functools import wraps from fastapi import FastAPI from pydantic import BaseModel class SampleModel(BaseModel): name: str age: int app = FastAPI() def auth_required(func): @wraps(func) async def wrapper(*args, **kwargs): return await func(*args, **kwargs) return wrapper @app.post(“https://stackoverflow.com/”) @auth_required … Read more

Why no @override decorator in Python to help code readability? [closed]

The problem with trying to add @override is that at method definition time, the decorator has no way to tell whether or not the method actually overrides another method. It doesn’t have access to the parent classes (or the current class, which doesn’t even exist yet!). If you want to add @override, the @override decorator … Read more

How can I get a Python decorator to run after the decorated function has completed?

Decorators usually return a wrapper function; just put your logic in the wrapper function after invoking the wrapped function. def audit_action(action): def decorator_func(func): def wrapper_func(*args, **kwargs): # Invoke the wrapped function first retval = func(*args, **kwargs) # Now do something here with retval and/or action print(‘In wrapper_func, handling action {!r} after wrapped function returned {!r}’.format(action, … Read more