Python Decorator

A Python Decorator is a programming language design pattern in Python code.

• See: KFP Pipeline, Callable Object.

---

---

References

2023

• chat
  • Q: what is a Python decorator?
  • A: In Python, a decorator is a design pattern that allows developers to add new functionality to an existing object without modifying its structure. Decorators are implemented as callable objects (functions, classes, or methods) that take an existing object (a function, class, or method) as an input and return a modified or enhanced version of that object.

    In practice, decorators are defined using the "@" symbol, followed by the name of the decorator function. The decorator function is defined just like a normal function, but it takes a single input, which is the object being decorated. Inside the decorator function, you can define additional behavior or modify the behavior of the input object.

    Here is an example of a simple decorator that adds a "hello" message to a function:

def my_decorator(func):
   def wrapper():
       print("Hello!")
       func()
   return wrapper

@my_decorator
def my_function():
   print("Goodbye!")

• • Here, the my_decorator function takes another function as an input and returns a new function called wrapper. When my_function is decorated with @my_decorator, Python internally replaces my_function with wrapper and when you call my_function it will print "Hello!" first, and then "Goodbye!"

     Decorators in KFP pipelines are used to define pipeline structure, components, inputs, outputs and dependencies between them, it's a way to specify the pipeline behavior and structure without modifying the function that creates it, making the pipeline definition more readable and understandable.

    In summary, decorators are a way to add or modify behavior of function, classes and methods without modifying their source code. In KFP, decorators are used to define and structure the pipeline behavior.

---