I'm trying to import a module in C++; the module resides in a package and should be accessed like:
from x.y import class1,func1, const1, etc
I'm on Python 3.6 and for this version what I have found so far is to use PyRun_SimpleString to do the import and then use PyImport_AddModuleObject to have a handle to my module. that is:
PyRun_SimpleString("from PacKage1 import Module1 as Module1");
auto module = PyImport_AddModuleObject(PyUnicode_DecodeFSDefault("Module1"));
so that down the road I can access its different attributes, something like this:
auto args = Py_BuildValue("sOOOOONNiN", model_name, model_checkpoint_path, align_fn,
bank_folder_root, cache_folder, postfix,
rebuild_cache, use_jit, threshold, device);
if (module != nullptr) {
// dict is a borrowed reference.
auto pdict = PyModule_GetDict(module);
if (pdict == nullptr) {
cout << "Fails to get the dictionary.\n";
return 1;
}
//Py_DECREF(module);
PyObject *pKeys = PyDict_Keys(pdict);
PyObject *pValues = PyDict_Values(pdict);
map<string, string> my_map;
//cout << "size: " << PyDict_Size(pdict)<<endl;
char* cstr_key = new char[100];
char* cstr_value = new char[500];
for (Py_ssize_t i = 0; i < PyDict_Size(pdict); ++i) {
PyArg_Parse(PyList_GetItem(pKeys, i), "s", &cstr_key);
PyArg_Parse(PyList_GetItem(pValues, i), "s", &cstr_value);
//cout << cstr<< " "<< cstr2 <<endl;
my_map.emplace(cstr_key, cstr_value);
}
for (auto x : my_map)
{
cout << x.first << " : " << x.second << endl;
}
system("pause");
// Builds the name of a callable class
auto python_class = PyDict_GetItemString(pdict, "MyClass1");
system("pause");
if (python_class == nullptr) {
cout << "Fails to get the Python class.\n";
return 1;
}
//Py_DECREF(pdict);
cout << python_class;
PyObject* object;
// Creates an instance of the class
if (PyCallable_Check(python_class)) {
object = PyObject_CallObject(python_class, args);
Py_DECREF(python_class);
}
else {
std::cout << "Cannot instantiate the Python class" << endl;
Py_DECREF(python_class);
return 1;
}
auto val = PyObject_CallMethod(object, "is_jit_model_available", NULL);
if (!val)
cout << "error!";
cout << val;
When I try to run this code, I get this output which shows the maps contents:
size: 5
__doc__ : Module1
__loader__ : Module1
__name__ : Module1
__package__ : Module1
__spec__ : Module1
So this is the result of PyModule_GetDict(module); However, when it comes to the class extraction from this module, it fails, that is, the PyDict_GetItemString(pdict, "MyClass1"); returns null.
It seems to me the module handler itself is not right and that is probably because maybe it doesn't point to the actual module which means I completely failed at importing and getting a handle to that module.
Therefore I can't think of any other way that allows me to import a module and use it like this.
What am I missing here?
As pointed in the comments, my initial attempt for importing the module is completely wrong, and instead I should have done this :
auto module = PyImport_ImportModule("Package1.Module1");
so I did so :
auto module = PyImport_ImportModule("FV.F_V");
After doing this, now I get much more meaningful output as you can see:
module: 0000021306FF9B38
size: 30
FaceVerification: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
Image: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
Path: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
__builtins__: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
__cached__: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
__doc__: FV.F_V
__file__: C:\Users\Master\Anaconda3\Lib\site-packages\FV\F_V.py
__loader__: FV
__name__: FV.F_V
__package__: FV
__spec__: FV
__warningregistry__ : C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
align_face: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
cv2: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
data_transforms: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
get_central_face_attributes: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
math: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
nn: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
np: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
os: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
pickle: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
plt: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
resnet101: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
resnet18: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
resnet50: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
scipy: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
time: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
torch: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
tqdm: C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc
transforms : C:\Users\Master\Anaconda3\Lib\site-packages\FV\__pycache__\F_V.cpython-36.pyc