Merge pull request #2346 from trenkel/master

Add CollectdError exception which can be thrown without causing a stacktrace to be logged.

diff --git a/src/collectd-python.pod b/src/collectd-python.pod
index 7a19f45..1f46f6f 100644 (file)
--- a/src/collectd-python.pod
+++ b/src/collectd-python.pod
@@ -68,8 +68,10 @@ use multiple B<ModulePath> lines to add more than one directory.
 If a Python script throws an exception it will be logged by collectd with the
 name of the exception and the message. If you set this option to true it will
 also log the full stacktrace just like the default output of an interactive
-Python interpreter. This should probably be set to false most of the time but
-is very useful for development and debugging of new modules.
+Python interpreter. This does not apply to the CollectError exception, which
+will never log a stacktrace.
+This should probably be set to false most of the time but is very useful for
+development and debugging of new modules.
 
 =item B<Interactive> I<bool>
 
@@ -248,6 +250,18 @@ collectd you're done.
 The following complex types are used to pass values between the Python plugin
 and collectd:
 
+=head2 CollectdError
+
+This is an exception. If any Python script raises this exception it will
+still be treated like an error by collectd but it will be logged as a
+warning instead of an error and it will never generate a stacktrace.
+
+ class CollectdError(Exception)
+
+Basic exception for collectd Python scripts.
+Throwing this exception will not cause a stacktrace to be logged, even if
+LogTraces is enabled in the config.
+
 =head2 Signed
 
 The Signed class is just a long. It has all its methods and behaves exactly

diff --git a/src/cpython.h b/src/cpython.h
index 04fad0c..38951c0 100644 (file)
--- a/src/cpython.h
+++ b/src/cpython.h
@@ -144,17 +144,21 @@ void cpy_log_exception(const char *context);
 /* Python object declarations. */
 
 typedef struct {
+  // clang-format off
   PyObject_HEAD         /* No semicolon! */
-      PyObject *parent; /* Config */
+  PyObject *parent;     /* Config */
   PyObject *key;        /* String */
   PyObject *values;     /* Sequence */
   PyObject *children;   /* Sequence */
+  // clang-format on
 } Config;
 extern PyTypeObject ConfigType;
 
 typedef struct {
+  // clang-format off
   PyObject_HEAD /* No semicolon! */
-      double time;
+  double time;
+  // clang-format on
   char host[DATA_MAX_NAME_LEN];
   char plugin[DATA_MAX_NAME_LEN];
   char plugin_instance[DATA_MAX_NAME_LEN];

diff --git a/src/python.c b/src/python.c
index d27e958..e60ba45 100644 (file)
--- a/src/python.c
+++ b/src/python.c
@@ -233,6 +233,12 @@ static char reg_shutdown_doc[] =
     "The callback function will be called with no parameters except for\n"
     "    data if it was supplied.";
 
+static char CollectdError_doc[] =
+    "Basic exception for collectd Python scripts.\n"
+    "\n"
+    "Throwing this exception will not cause a stacktrace to be logged, \n"
+    "even if LogTraces is enabled in the config.";
+
 static pthread_t main_thread;
 static PyOS_sighandler_t python_sigint_handler;
 static _Bool do_interactive = 0;
@@ -244,7 +250,7 @@ static _Bool do_interactive = 0;
 
 static PyThreadState *state;
 
-static PyObject *sys_path, *cpy_format_exception;
+static PyObject *sys_path, *cpy_format_exception, *CollectdError;
 
 static cpy_callback_t *cpy_config_callbacks;
 static cpy_callback_t *cpy_init_callbacks;
@@ -300,7 +306,7 @@ static void cpy_build_name(char *buf, size_t size, PyObject *callback,
 }
 
 void cpy_log_exception(const char *context) {
-  int l = 0;
+  int l = 0, collectd_error;
   const char *typename = NULL, *message = NULL;
   PyObject *type, *value, *traceback, *tn, *m, *list;
 
@@ -308,6 +314,7 @@ void cpy_log_exception(const char *context) {
   PyErr_NormalizeException(&type, &value, &traceback);
   if (type == NULL)
     return;
+  collectd_error = PyErr_GivenExceptionMatches(value, CollectdError);
   tn = PyObject_GetAttrString(type, "__name__"); /* New reference. */
   m = PyObject_Str(value);                       /* New reference. */
   if (tn != NULL)
@@ -318,11 +325,17 @@ void cpy_log_exception(const char *context) {
     typename = "NamelessException";
   if (message == NULL)
     message = "N/A";
-  Py_BEGIN_ALLOW_THREADS ERROR("Unhandled python exception in %s: %s: %s",
-                               context, typename, message);
-  Py_END_ALLOW_THREADS Py_XDECREF(tn);
+  Py_BEGIN_ALLOW_THREADS;
+  if (collectd_error) {
+    WARNING("%s in %s: %s", typename, context, message);
+  } else {
+    ERROR("Unhandled python exception in %s: %s: %s", context, typename,
+          message);
+  }
+  Py_END_ALLOW_THREADS;
+  Py_XDECREF(tn);
   Py_XDECREF(m);
-  if (!cpy_format_exception || !traceback) {
+  if (!cpy_format_exception || !traceback || collectd_error) {
     PyErr_Clear();
     Py_DECREF(type);
     Py_XDECREF(value);
@@ -356,10 +369,11 @@ void cpy_log_exception(const char *context) {
     if (cpy[strlen(cpy) - 1] == '\n')
       cpy[strlen(cpy) - 1] = 0;
 
-    Py_BEGIN_ALLOW_THREADS ERROR("%s", cpy);
-    Py_END_ALLOW_THREADS
+    Py_BEGIN_ALLOW_THREADS;
+    ERROR("%s", cpy);
+    Py_END_ALLOW_THREADS;
 
-        free(cpy);
+    free(cpy);
   }
 
   Py_XDECREF(list);
@@ -410,9 +424,10 @@ static int cpy_write_callback(const data_set_t *ds,
       PyList_SetItem(
           list, i, PyLong_FromUnsignedLongLong(value_list->values[i].absolute));
     } else {
-      Py_BEGIN_ALLOW_THREADS ERROR("cpy_write_callback: Unknown value type %d.",
-                                   ds->ds[i].type);
-      Py_END_ALLOW_THREADS Py_DECREF(list);
+      Py_BEGIN_ALLOW_THREADS;
+      ERROR("cpy_write_callback: Unknown value type %d.", ds->ds[i].type);
+      Py_END_ALLOW_THREADS;
+      Py_DECREF(list);
       CPY_RETURN_FROM_THREADS 0;
     }
     if (PyErr_Occurred() != NULL) {
@@ -706,8 +721,10 @@ static PyObject *cpy_flush(PyObject *self, PyObject *args, PyObject *kwds) {
   if (PyArg_ParseTupleAndKeywords(args, kwds, "|etiet", kwlist, NULL, &plugin,
                                   &timeout, NULL, &identifier) == 0)
     return NULL;
-  Py_BEGIN_ALLOW_THREADS plugin_flush(plugin, timeout, identifier);
-  Py_END_ALLOW_THREADS PyMem_Free(plugin);
+  Py_BEGIN_ALLOW_THREADS;
+  plugin_flush(plugin, timeout, identifier);
+  Py_END_ALLOW_THREADS;
+  PyMem_Free(plugin);
   PyMem_Free(identifier);
   Py_RETURN_NONE;
 }
@@ -843,8 +860,10 @@ static PyObject *cpy_error(PyObject *self, PyObject *args) {
   char *text;
   if (PyArg_ParseTuple(args, "et", NULL, &text) == 0)
     return NULL;
-  Py_BEGIN_ALLOW_THREADS plugin_log(LOG_ERR, "%s", text);
-  Py_END_ALLOW_THREADS PyMem_Free(text);
+  Py_BEGIN_ALLOW_THREADS;
+  plugin_log(LOG_ERR, "%s", text);
+  Py_END_ALLOW_THREADS;
+  PyMem_Free(text);
   Py_RETURN_NONE;
 }
 
@@ -852,8 +871,10 @@ static PyObject *cpy_warning(PyObject *self, PyObject *args) {
   char *text;
   if (PyArg_ParseTuple(args, "et", NULL, &text) == 0)
     return NULL;
-  Py_BEGIN_ALLOW_THREADS plugin_log(LOG_WARNING, "%s", text);
-  Py_END_ALLOW_THREADS PyMem_Free(text);
+  Py_BEGIN_ALLOW_THREADS;
+  plugin_log(LOG_WARNING, "%s", text);
+  Py_END_ALLOW_THREADS;
+  PyMem_Free(text);
   Py_RETURN_NONE;
 }
 
@@ -861,8 +882,10 @@ static PyObject *cpy_notice(PyObject *self, PyObject *args) {
   char *text;
   if (PyArg_ParseTuple(args, "et", NULL, &text) == 0)
     return NULL;
-  Py_BEGIN_ALLOW_THREADS plugin_log(LOG_NOTICE, "%s", text);
-  Py_END_ALLOW_THREADS PyMem_Free(text);
+  Py_BEGIN_ALLOW_THREADS;
+  plugin_log(LOG_NOTICE, "%s", text);
+  Py_END_ALLOW_THREADS;
+  PyMem_Free(text);
   Py_RETURN_NONE;
 }
 
@@ -870,8 +893,10 @@ static PyObject *cpy_info(PyObject *self, PyObject *args) {
   char *text;
   if (PyArg_ParseTuple(args, "et", NULL, &text) == 0)
     return NULL;
-  Py_BEGIN_ALLOW_THREADS plugin_log(LOG_INFO, "%s", text);
-  Py_END_ALLOW_THREADS PyMem_Free(text);
+  Py_BEGIN_ALLOW_THREADS;
+  plugin_log(LOG_INFO, "%s", text);
+  Py_END_ALLOW_THREADS;
+  PyMem_Free(text);
   Py_RETURN_NONE;
 }
 
@@ -880,8 +905,10 @@ static PyObject *cpy_debug(PyObject *self, PyObject *args) {
   char *text;
   if (PyArg_ParseTuple(args, "et", NULL, &text) == 0)
     return NULL;
-  Py_BEGIN_ALLOW_THREADS plugin_log(LOG_DEBUG, "%s", text);
-  Py_END_ALLOW_THREADS PyMem_Free(text);
+  Py_BEGIN_ALLOW_THREADS;
+  plugin_log(LOG_DEBUG, "%s", text);
+  Py_END_ALLOW_THREADS;
+  PyMem_Free(text);
 #endif
   Py_RETURN_NONE;
 }
@@ -1063,13 +1090,14 @@ static int cpy_shutdown(void) {
   }
   PyErr_Print();
 
-  Py_BEGIN_ALLOW_THREADS cpy_unregister_list(&cpy_config_callbacks);
+  Py_BEGIN_ALLOW_THREADS;
+  cpy_unregister_list(&cpy_config_callbacks);
   cpy_unregister_list(&cpy_init_callbacks);
   cpy_unregister_list(&cpy_shutdown_callbacks);
   cpy_shutdown_triggered = 1;
-  Py_END_ALLOW_THREADS
+  Py_END_ALLOW_THREADS;
 
-      if (!cpy_num_callbacks) {
+  if (!cpy_num_callbacks) {
     Py_Finalize();
     return 0;
   }
@@ -1212,7 +1240,7 @@ PyMODINIT_FUNC PyInit_collectd(void) {
 
 static int cpy_init_python(void) {
   PyOS_sighandler_t cur_sig;
-  PyObject *sys;
+  PyObject *sys, *errordict;
   PyObject *module;
 
 #ifdef IS_PY3K
@@ -1239,6 +1267,11 @@ static int cpy_init_python(void) {
   PyType_Ready(&SignedType);
   UnsignedType.tp_base = &PyLong_Type;
   PyType_Ready(&UnsignedType);
+  errordict = PyDict_New();
+  PyDict_SetItemString(
+      errordict, "__doc__",
+      cpy_string_to_unicode_or_bytes(CollectdError_doc)); /* New reference. */
+  CollectdError = PyErr_NewException("collectd.CollectdError", NULL, errordict);
   sys = PyImport_ImportModule("sys"); /* New reference. */
   if (sys == NULL) {
     cpy_log_exception("python initialization");
@@ -1268,6 +1301,9 @@ static int cpy_init_python(void) {
                      (void *)&SignedType); /* Steals a reference. */
   PyModule_AddObject(module, "Unsigned",
                      (void *)&UnsignedType); /* Steals a reference. */
+  Py_XINCREF(CollectdError);
+  PyModule_AddObject(module, "CollectdError",
+                     CollectdError); /* Steals a reference. */
   PyModule_AddIntConstant(module, "LOG_DEBUG", LOG_DEBUG);
   PyModule_AddIntConstant(module, "LOG_INFO", LOG_INFO);
   PyModule_AddIntConstant(module, "LOG_NOTICE", LOG_NOTICE);

diff --git a/src/pyvalues.c b/src/pyvalues.c
index d1bdedd..15c1848 100644 (file)
--- a/src/pyvalues.c
+++ b/src/pyvalues.c
@@ -1280,7 +1280,7 @@ PyTypeObject SignedType = {
     0,                                        /* tp_getattro */
     0,                                        /* tp_setattro */
     0,                                        /* tp_as_buffer */
-    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */
     Signed_doc                                /* tp_doc */
 };
 
@@ -1307,6 +1307,6 @@ PyTypeObject UnsignedType = {
     0,                                        /* tp_getattro */
     0,                                        /* tp_setattro */
     0,                                        /* tp_as_buffer */
-    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */
     Unsigned_doc                              /* tp_doc */
 };