%ModuleCode

#include "qgsprocessingexception.h"

QString getTraceback()

{

#define TRACEBACK_FETCH_ERROR(what) {errMsg = what; goto done;}

// acquire global interpreter lock to ensure we are in a consistent state

PyGILState_STATE gstate;

gstate = PyGILState_Ensure();

QString errMsg;

QString result;

PyObject *modStringIO = nullptr;

PyObject *modTB = nullptr;

PyObject *obStringIO = nullptr;

PyObject *obResult = nullptr;

PyObject *type, *value, *traceback;

PyErr_Fetch( &type, &value, &traceback );

PyErr_NormalizeException( &type, &value, &traceback );

const char *iomod = "io";

modStringIO = PyImport_ImportModule( iomod );

if ( !modStringIO )

TRACEBACK_FETCH_ERROR( QString( "can't import %1" ).arg( iomod ) );

obStringIO = PyObject_CallMethod( modStringIO, ( char * ) "StringIO", nullptr );

/* Construct a cStringIO object */

if ( !obStringIO )

TRACEBACK_FETCH_ERROR( "cStringIO.StringIO() failed" );

modTB = PyImport_ImportModule( "traceback" );

if ( !modTB )

TRACEBACK_FETCH_ERROR( "can't import traceback" );

obResult = PyObject_CallMethod( modTB, ( char * ) "print_exception",

( char * ) "OOOOO",

type, value ? value : Py_None,

traceback ? traceback : Py_None,

Py_None,

obStringIO );

if ( !obResult )

TRACEBACK_FETCH_ERROR( "traceback.print_exception() failed" );

Py_DECREF( obResult );

obResult = PyObject_CallMethod( obStringIO, ( char * ) "getvalue", nullptr );

if ( !obResult )

TRACEBACK_FETCH_ERROR( "getvalue() failed." );

/* And it should be a string all ready to go - duplicate it. */

if ( !PyUnicode_Check( obResult ) )

TRACEBACK_FETCH_ERROR( "getvalue() did not return a string" );

result = QString::fromUtf8( PyUnicode_AsUTF8( obResult ) );

done:

// All finished - first see if we encountered an error

if ( result.isEmpty() && !errMsg.isEmpty() )

{

result = errMsg;

}

Py_XDECREF( modStringIO );

Py_XDECREF( modTB );

Py_XDECREF( obStringIO );

Py_XDECREF( obResult );

Py_XDECREF( value );

Py_XDECREF( traceback );

Py_XDECREF( type );

// we are done calling python API, release global interpreter lock

PyGILState_Release( gstate );

return result;

}

%End

%VirtualErrorHandler processing_exception_handler

throw QgsProcessingException( getTraceback() );

%End