Method callPyObjMethod

src/EmbedPython/EmbeddedPython.cpp:456–514

given an existing python object instance, invoke one of its methods grabs mutex to prevent need for Python GIL

// given an existing python object instance, invoke one of its methods 
// grabs mutex to prevent need for Python GIL
QVariant EmbeddedPython::callPyObjMethod(PyObjectPtr &pyobj, 
                                         const QString &methname, 
                                         const QVariantList &args, 
                                         int *rv, 
                                         QString &tb,
                                         bool ret_python_object)
{
    EmbeddedPython::m_mutex.lock();
    PyGILState_STATE gstate = PyGILState_Ensure();

    QVariant  res        = QVariant(QString());
    PyObject* obj        = pyobj.object();
    PyObject* func       = NULL;
    PyObject* pyargs     = NULL;
    PyObject* pyres      = NULL;
    int       idx        = 0;
     
    func = PyObject_GetAttrString(obj,methname.toUtf8().constData());
    if (func == NULL) {
         *rv = -1;
         goto cleanup;
    }

    if (!PyCallable_Check(func)) {
        *rv = -2;
        goto cleanup;
    }

    // Build up Python argument List from args
    pyargs = PyTuple_New(args.size());
    idx = 0;
    foreach(QVariant arg, args) {
        PyTuple_SetItem(pyargs, idx, QVariantToPyObject(arg));
        idx++;
    }

    pyres = PyObject_CallObject(func, pyargs);
    if (pyres == NULL) {
        *rv = -3;
        goto cleanup;
    }

    *rv = 0;

    res = PyObjectToQVariant(pyres, ret_python_object);

    cleanup:
    if (PyErr_Occurred() != NULL) {
        QString default_error = "Python Object Method Invocation Error: " + methname;
        tb = getPythonErrorTraceback(default_error);
     }
    Py_XDECREF(pyres);
    Py_XDECREF(pyargs);
    Py_XDECREF(func);

    PyGILState_Release(gstate);
    EmbeddedPython::m_mutex.unlock();
    return res;