How do I programatically find what symbols were imported with Python import * command?

Question

I have a system that collects all classes that derive from certain base classes and stores them in a dictionary. I want to avoid having to specify which classes are available (I would like to discover them programatically), so have used a from ModuleName import * statement. The user is then directed to place all tests to be collected in the ModuleName module. However, I cannot find a way to programatically determine what symbols were imported with that import statement. I have tried using dir() and __dict__ as indicated in the following example, but to no avail. How does one programatically find symbols imported in this manner (with import *)? I am unable to find them with the above methods.

testTypeFigureOuterrer.py:

from testType1 import *
from testType2 import *

class TestFigureOuterrer(object):

    def __init__(self):
        self.existingTests = {'type1':{},'type2':{}}

    def findAndSortTests(self):

        for symbol in dir(): # Also tried: dir(self) and __dict__
            try:
                thing = self.__getattribute__(symbol)
            except AttributeError:
                continue
            if issubclass(thing,TestType1):
                self.existingTests['type1'].update( dict(symbol,thing) )
            elif issubclass(thing,TestType3):
                self.existingTests['type2'].update( dict(symbol,thing) )
            else:
                continue

if __name__ == "__main__":
    testFigureOuterrer = TestFigureOuterrer()
    testFigureOuterrer.findAndSortTests()

testType1.py:

class TestType1(object):
    pass

class TestA(TestType1):
    pass

class TestB(TestType1):
    pass

testType2.py:

class TestType2:
    pass

class TestC(TestType2):
    pass

class TestD(TestType2):
    pass

Answer 1

Since you know the imports yourself, you should just import the module manually again, and then check the contents of the module. If an __all__ property is defined, its contents are imported as names when you do from module import *. Otherwise, just use all its members:

def getImportedNames (module):
    names = module.__all__ if hasattr(module, '__all__') else dir(module)
    return [name for name in names if not name.startswith('_')]

This has the benefit that you do not need to go through the globals, and filter everything out. And since you know the modules you import from at design time, you can also check them directly.

from testType1 import *
from testType2 import *

import testType1, testType2

print(getImportedNames(testType1))
print(getImportedNames(testType2))

Alternatively, you can also look up the module by its module name from sys.modules, so you don’t actually need the extra import:

import sys
def getImportedNames (moduleName):
    module = sys.modules[moduleName]
    names = module.__all__ if hasattr(module, '__all__') else dir(module)
    return [name for name in names if not name.startswith('_')]

print(getImportedNames('testType1'))
print(getImportedNames('testType2'))