Print function name in the function itself

Question

I have many functions like:

def DBworker_thatdoes_job7():
    print "DBworker_thatdoes_job7 starting..."

    ... the actual code here ...

    print "DBworker_thatdoes_job7 finished."

How to do this without hardcoding the function names? Here is what I want to achieve:

def DBworker_thatdoes_job7():
    print thisfunction.name + " starting..."
    ...

def DBworker_thatdoes_cleaning18():
    print thisfunction.name + " starting..."
    ...

Note: I've already looked at How to get a function name as a string in Python? but I don't really see a nice way to do it here. Also, this question is close to Determine function name from within that function (without using traceback) but here applied to the specific use case of function-name logging at startup and end, thus not exactly a duplicate.

Possible duplicate of [Determine function name from within that function (without using traceback)](https://stackoverflow.com/questions/5067604/determine-function-name-from-within-that-function-without-using-traceback) — sjw, Apr 18 '18 at 14:30
If you use the `logging` module to produce this type of output, you can use the format string `'%(funcName)s ...'`, and the logged message will include the name of the function. — chepner, Apr 18 '18 at 14:40

score 6 · Accepted Answer · answered Apr 18 '18 at 14:33

6

you could use a decorator:

def start_finish(f):
    def new_f(*args, **kwargs):
        print("starting", f.__name__)
        f(*args, **kwargs)
        print("finished", f.__name__)
    return new_f

@start_finish
def function():
    print('function body')

function()

this prints:

starting function
function body
finished function

answered Apr 18 '18 at 14:33

hiro protagonist

44,693
14
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Very nice solution! The first time I really see the benefits of decorators and will finally use them :) – Basj Apr 18 '18 at 14:35

score 2 · Answer 2 · answered Apr 18 '18 at 14:33

2

Perhaps a decorator?

def log_function_start(fn):
    def wrapper(*args, **kwargs):
        print '{} starting...'.format(fn.__name__)
        fn(*args, **kwargs)
    return wrapper

@log_function_start
def DBworker_thatdoes_job7():
    ...

answered Apr 18 '18 at 14:33

0x5453

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1
32
61

Very nice solution too! – Basj Apr 18 '18 at 14:35

score 0 · Answer 3 · answered Apr 18 '18 at 14:32

You have more leeway to customize your function if you manually implement a callable, i.e. by creating a class with a __call__ method.

>>> class foo(object): # or class foo: in Python 3
...     def __call__(self):
...         # your logic goes here
...         print(type(self).__name__)
... 
>>> foo = foo()
>>> foo()
foo

Print function name in the function itself

3 Answers3