python - Get source script details, similar to inspect.getmembers() without importing the script -


i'm trying source, callee list, defaults, keywords, args , varargs of functions in python script.

currently, i'm importing module , using python inspect module's getmembers function , passing isfunction parameter so:

members = inspect.getmembers(mymodule, inspect.isfunction)

however, method doesn't work if mymodule's imports aren't available me (since mymodule has imported first).

i tried using python ast module parse , dump syntax tree, getting function source involved hacky techniques and/or questionable , far maintainable third party libraries. believe i've scoured documentation , stackoverflow pretty thoroughly , have failed find suitable solution. missing something?

a possible workaround monkeypatch __import__ function custom function never throws importerror , returns dummy module instead:

def force_import(module):     original_import = __import__      def fake_import(*args):         try:             return original_import(*args)         except importerror:             return __builtins__     __builtins__.__import__ = fake_import      module = original_import(module)      __builtins__.__import__ = original_import     return module

this allow import mymodule if dependencies cannot imported. can use inspect.getmembers would:

mymodule = force_import('mymodule') members = inspect.getmembers(mymodule, inspect.isfunction)

a problem solution works around failing imports. if mymodule tries access members of imported modules, import fail:

# mymodule.py  import this_module_doesnt_exist # works  print(this_module_doesnt_exist.variable) # fails 
force_import('mymodule') # attributeerror: module 'builtins' has no attribute 'variable'

in order work around this, can create dummy class never throws attributeerror:

class dummyvalue:     def __call__(self, *args, **kwargs):         return self      __getitem__ = __setitem__ = __delitem__ = __call__     __len__ = __length_hint__ = __bool__ = __call__     __iter__ = __next__ = __call__     __getattribute__ = __call__     __enter__ = __leave__ = __call__     __str__ = __repr__ = __format__ = __bytes__ = __call__     # etc

(see the data model documentation list of dunder methods may have implement.)

now if force_import returns instance of class (change return __builtins__ return dummyvalue()), importing mymodule succeed.


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