knowrob::PythonError Class Reference

#include <PythonError.h>

Inheritance diagram for knowrob::PythonError:

Collaboration diagram for knowrob::PythonError:

Classes
struct	ErrorData

Public Member Functions
	PythonError ()
	PythonError ()
Public Member Functions inherited from knowrob::KnowRobError
	KnowRobError (std::string_view exc_type, std::string_view msg)
	KnowRobError (std::string_view exc_type, std::string_view msg, std::string_view trace)
	KnowRobError (std::string_view exc_type, std::string_view msg, std::string_view file, int line)
	KnowRobError (std::string_view exc_type, std::string_view msg, std::string_view file, int line, std::string_view trace)
void	setFile (std::string_view file)
void	setLine (int line)
auto	file () const
auto	line () const
bool	hasFile () const
	KnowRobError (std::string_view exc_type, std::string_view msg)
	KnowRobError (std::string_view exc_type, std::string_view msg, std::string_view trace)
	KnowRobError (std::string_view exc_type, std::string_view msg, std::string_view file, int line)
	KnowRobError (std::string_view exc_type, std::string_view msg, std::string_view file, int line, std::string_view trace)
void	setFile (std::string_view file)
void	setLine (int line)
auto	file () const
auto	line () const
bool	hasFile () const

Protected Member Functions
	PythonError (const ErrorData &errorData)
	PythonError (const ErrorData &errorData)

Static Protected Member Functions
static ErrorData	makeErrorData ()
static ErrorData	makeErrorData ()

Protected Attributes
ErrorData	errorData_
Protected Attributes inherited from knowrob::KnowRobError
std::optional< std::string >	file_
int	line_

Detailed Description

An error that is thrown when a Python error occurs. It contains the current error message, the type of the exception and the stack trace extracted from the Python interpreter.

Definition at line 18 of file PythonError.h.

Constructor & Destructor Documentation

PythonError() [1/4]

PythonError::PythonError

(

)

Definition at line 32 of file PythonError.cpp.

        : PythonError(makeErrorData()) {
}

PythonError() [2/4]

PythonError::PythonError ( const ErrorData &  errorData )

explicitprotected

Definition at line 21 of file PythonError.cpp.

        : KnowRobError(errorData.exc_type, errorData.exc_msg, errorData.exc_trace),
          errorData_(errorData) {
    if (errorData_.exc_file.has_value()) {
        setFile(errorData_.exc_file.value());
    }
    if (errorData_.exc_line.has_value()) {
        setLine(errorData_.exc_line.value());
    }
}

PythonError() [3/4]

knowrob::PythonError::PythonError

(

)

PythonError() [4/4]

knowrob::PythonError::PythonError ( const ErrorData &  errorData )

explicitprotected

Member Function Documentation

makeErrorData() [1/2]

PythonError::ErrorData PythonError::makeErrorData ( )

staticprotected

Definition at line 36 of file PythonError.cpp.

                                                {
    using namespace boost::python;
 
    ErrorData errorData;
    if (!PyErr_Occurred()) {
        // no python error occurred
        KB_WARN("PythonError was created even though no error occurred in Python!");
        return errorData;
    }
 
    // try to fetch the Python error
    PyObject * py_type, *py_value, *py_traceback;
    PyErr_Fetch(&py_type, &py_value, &py_traceback);
    if (!py_type) {
        KB_WARN("PythonError was created but PyErr_Fetch returned nullptr for error type.");
        return errorData;
    }
    PyErr_NormalizeException(&py_type, &py_value, &py_traceback);
    if (py_traceback != nullptr) {
        PyException_SetTraceback(py_value, py_traceback);
    }
 
    // Get Boost handles to the Python objects so we get an easier API.
    handle<> h_type(py_type);
    handle<> h_value(allow_null(py_value));
    handle<> h_traceback(allow_null(py_traceback));
 
    // extract name of error type
    auto e_type = extract<std::string>(object(h_type).attr("__name__"));
    if (e_type.check()) {
        errorData.exc_type = e_type();
    } else {
        errorData.exc_type = "UnknownError";
    }
 
    // extract error msg by using __str__ method of h_value
    if (h_value) {
        auto e_message = extract<std::string>(object(h_value).attr("__str__")());
        if (e_message.check()) {
            errorData.exc_msg = e_message();
        }
    }
 
    // finally handle traceback if any
    if (h_traceback) {
        object o_traceback(h_traceback);
        // extract the line number from the traceback
        auto tb_lineno = extract<long>(o_traceback.
                attr("tb_lineno"));
        if (tb_lineno.check()) {
            errorData.exc_line = tb_lineno;
        }
        // extract the file path from the traceback
        auto e_file_path = extract<std::string>(o_traceback.
                attr("tb_frame").
                attr("f_code").
                attr("co_filename"));
        if (e_file_path.check()) {
            errorData.exc_file = e_file_path();
        }
 
        // Import the `traceback` module and use it to format the exception.
        object format_tb = import("traceback").
                attr("format_tb");
        // Extract the formatted traceback using `format_tb`
        object formatted_list = format_tb(o_traceback);
        object formatted_traceback = str("\n").join(formatted_list).slice(0, -1);
        auto str_traceback = extract<std::string>(formatted_traceback);
        if (str_traceback.check()) {
            errorData.exc_trace = str_traceback();
        }
    }
 
    return errorData;
}

makeErrorData() [2/2]

static ErrorData knowrob::PythonError::makeErrorData ( )

staticprotected

Member Data Documentation

errorData_

ErrorData knowrob::PythonError::errorData_

protected

Definition at line 31 of file PythonError.h.

---

The documentation for this class was generated from the following files:

• build/_CPack_Packages/Linux/DEB/knowrob-2.1.0-Linux/usr/include/knowrob/integration/python/PythonError.h
• src/integration/python/PythonError.cpp