LSSTApplications  17.0+124,17.0+14,17.0+73,18.0.0+37,18.0.0+80,18.0.0-4-g68ffd23+4,18.1.0-1-g0001055+12,18.1.0-1-g03d53ef+5,18.1.0-1-g1349e88+55,18.1.0-1-g2505f39+44,18.1.0-1-g5315e5e+4,18.1.0-1-g5e4b7ea+14,18.1.0-1-g7e8fceb+4,18.1.0-1-g85f8cd4+48,18.1.0-1-g8ff0b9f+4,18.1.0-1-ga2c679d+1,18.1.0-1-gd55f500+35,18.1.0-10-gb58edde+2,18.1.0-11-g0997b02+4,18.1.0-13-gfe4edf0b+12,18.1.0-14-g259bd21+21,18.1.0-19-gdb69f3f+2,18.1.0-2-g5f9922c+24,18.1.0-2-gd3b74e5+11,18.1.0-2-gfbf3545+32,18.1.0-26-g728bddb4+5,18.1.0-27-g6ff7ca9+2,18.1.0-3-g52aa583+25,18.1.0-3-g8ea57af+9,18.1.0-3-gb69f684+42,18.1.0-3-gfcaddf3+6,18.1.0-32-gd8786685a,18.1.0-4-gf3f9b77+6,18.1.0-5-g1dd662b+2,18.1.0-5-g6dbcb01+41,18.1.0-6-gae77429+3,18.1.0-7-g9d75d83+9,18.1.0-7-gae09a6d+30,18.1.0-9-gc381ef5+4,w.2019.45
LSSTDataManagementBasePackage
Exception.h
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1 /*
2  * This file is part of pex_exceptions.
3  *
4  * Developed for the LSST Data Management System.
5  * This product includes software developed by the LSST Project
6  * (https://www.lsst.org).
7  * See the COPYRIGHT file at the top-level directory of this distribution
8  * for details of code ownership.
9  *
10  * This program is free software: you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation, either version 3 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program. If not, see <https://www.gnu.org/licenses/>.
22  */
23 
24 #ifndef LSST_PEX_EXCEPTIONS_PYTHON_EXCEPTION_H
25 #define LSST_PEX_EXCEPTIONS_PYTHON_EXCEPTION_H
26 
27 #include <string>
28 
29 #include <pybind11/pybind11.h>
30 
32 
33 namespace lsst {
34 namespace pex {
35 namespace exceptions {
36 namespace python {
37 
51 template <typename T, typename E = lsst::pex::exceptions::Exception>
52 pybind11::class_<T, E> declareException(pybind11::module &mod, const std::string &name,
53  const std::string &base) {
54  namespace py = pybind11;
55 
56  // Wrap T as a new Python exception type with *name* and add it to the module
57  //
58  // Note that all created C++ wrapped type derive from Exception here.
59  // It is only in the pure Python wrapper layer that they get embedded in
60  // a subclass of the requested base.
61  py::class_<T, E> cls(mod, name.c_str());
62 
63  // Declare T wrapped by cls as a pex exception and register it
64  // this relies on the pure Python function "declare" defined in "wrappers"
65  // to create a corresponding Python type derived from Python standard Exception
66  auto exceptions =
67  py::reinterpret_steal<py::object>(PyImport_ImportModule("lsst.pex.exceptions.wrappers"));
68  if (!exceptions.ptr()) {
69  PyErr_SetString(PyExc_SystemError, "import failed");
70  throw py::error_already_set();
71  }
72 
73  auto declare = py::reinterpret_steal<py::object>(PyObject_GetAttrString(exceptions.ptr(), "declare"));
74  if (!declare.ptr()) {
75  PyErr_SetString(PyExc_SystemError, "could not get declare function from Python");
76  throw py::error_already_set();
77  }
78 
79  auto baseCls = py::reinterpret_steal<py::object>(PyObject_GetAttrString(exceptions.ptr(), base.c_str()));
80  if (!baseCls.ptr()) {
81  PyErr_SetString(PyExc_SystemError, "could not get base class");
82  throw py::error_already_set();
83  }
84 
85  auto exceptionName = py::reinterpret_steal<py::object>(PYBIND11_FROM_STRING(name.c_str()));
86  if (!exceptionName.ptr()) {
87  PyErr_SetString(PyExc_SystemError, "could not create name string");
88  throw py::error_already_set();
89  }
90 
91  auto result = py::reinterpret_steal<py::object>(PyObject_CallFunctionObjArgs(
92  declare.ptr(), mod.ptr(), exceptionName.ptr(), baseCls.ptr(), cls.ptr(), NULL));
93  if (!result.ptr()) {
94  PyErr_SetString(PyExc_SystemError, "could not declare exception");
95  throw py::error_already_set();
96  }
97 
98  return cls;
99 }
100 
101 } // namespace python
102 } // namespace exceptions
103 } // namespace pex
104 } // namespace lsst
105 
106 #endif
pybind11::class_< T, E > declareException(pybind11::module &mod, const std::string &name, const std::string &base)
Helper function for pybind11, used to define new types of exceptions.
Definition: Exception.h:52
STL class.
A base class for image defects.
Definition: __init__.py:1
Definition: __init__.py:1
T c_str(T... args)
def declare(module, exception_name, base, wrapped_class)
Definition: wrappers.py:153
py::object result
Definition: _schema.cc:429