timefunc function

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Justin,

In "Python for Security - creating a socket connection" you use a function called timefunc in utils.py. It measures the elapsed time for your main(). Can you elaborate on what how it works and why you invoke it with an @? Or if you can give me the episode where you created it, that would also help.

Love the Python series...

Thanks....

@Gary-Gordon
That is called a decorator function. This works by wrapping the existing function in another function, a decorating function, that allows for adding functionality to an existing function.

For example: Let's say that we have a function add that just adds two numbers.

def add(x, y):
    return x + y

However, the boss has come by an ask to add logging to that function so we know when it runs. How can we add this functionality for our application only without affecting the add function in other places? Let's decorate!

def logit(func):
    def wrapper(*args, **kwargs):
         print("Calling function: {}".format(func.__name__))
         results = func(*args, **kwargs) # down below this will be where **add** is called
         print("Called function: {}".format(func.__name__))
         print("Results: {}".format(results))
         return results
   return wrapper

add_with_logging = logit(add) # this is alternative to use the @ notation


results = add_with_logging(3, 2)
print("Results: (Expected -> 5) Actual -> {}".format(results))

Because we have writting this logit function, we can now add logging to any functions that we write ourselves. Instead of add_with_logging = logit(add), we can use the shorthand:

@logit
def create_connection(address):
    """Makes a connection"""
    ...code here...

Which will add logging to the create_connection function instead of us muddying up the internals of the function.

Decorators are convenient, but can take a bit to wrap your head around. Hope this helps.

It does, thank you. Where I was getting confused was "something happens before function", function happens, "something happens after function" - your timer function shows elapsed time. Now I understand how you got it. Also it was the first time I've seen the @ symbol used. Makes it easy to insert just about anywhere in your script.

Thanks for the help.

Yeah the reusability is where its at!