On Fri, 7 Aug 2020 at 09:26, Kazantcev Andrey heckad@yandex.ru wrote:
The problem in this code
lib.py
from json import dumps def some_func(): # do something res = dumps(...) # do somethingI wish dump and load themselves could take parameters from somewhere else, and that was the standard behaviour.
That's such a general statement, you could probably use it for *any* function, at some point. Which makes your argument pretty weak, IMO. And to be honest, the standard Python way of providing that behaviour is monkeypatching. It feels like a hack because the general view is that needing to do it is a sign of a badly designed API, is all.
For your example, if wanting to change the format of dumps is an important feature, lib.py "should" have been designed with a configuration mechanism that allows users to choose that format. The fact that it doesn't either implies that the author of lib.py doesn't want you to do that, or that they didn't think of it. Monkeypatching allows you to address that limitation, so in that sense it's a flexible but advanced mechanism, not a hack.
It's not particularly hard (as I'm sure you realise):
def custom_dumps(obj): json.dumps(obj, param1=preference1, ...)
old_val = lib.dumps try: lib.some_func() finally: lib.dumps = old_val
That needs an understanding of how lib.py works, and it needs you to accept the risk of using the library in a way that's not supported, but it's a perfectly reasonable approach for an unexpected case, IMO.
Paul