From 3f5629302abd2cfae97ef821da274384806d085a Mon Sep 17 00:00:00 2001 From: Tony Asleson Date: Tue, 8 Mar 2016 15:57:15 -0600 Subject: [PATCH] lvmdbus: Fix exception during exception handling Python 3.5 in F24 was throwing the following exception: Traceback (most recent call last): File "/usr/lib/python3.5/site-packages/lvmdbusd/main.py", line 73, in process_request req.run_cmd() File "/usr/lib/python3.5/site-packages/lvmdbusd/request.py", line 73, in run_cmd self.register_error(-1, st) File "/usr/lib/python3.5/site-packages/lvmdbusd/request.py", line 123, in register_error self._reg_ending(None, error_rc, error) File "/usr/lib/python3.5/site-packages/lvmdbusd/request.py", line 115, in _reg_ending self.cb_error(self._rc_error) File "/usr/lib64/python3.5/site-packages/dbus/service.py", line 669, in keywords[error_callback] = lambda exception: _method_reply_error(connection, message, exception) File "/usr/lib64/python3.5/site-packages/dbus/service.py", line 293, in _method_reply_error exception)) File "/usr/lib64/python3.5/traceback.py", line 136, in format_exception_only return list(TracebackException(etype, value, None).format_exception_only()) File "/usr/lib64/python3.5/traceback.py", line 442, in __init__ if (exc_value and exc_value.__cause__ is not None AttributeError: 'str' object has no attribute '__cause__' This was caused because we were calling the dbus error callback with a string instead of an actual exception. On python 3.4 this was apparently OK, but not with 3.5. Corrected to pass the exception to error callback. Change tested on both python 3.4 and 3.5. Reported-by: Vratislav Podzimek Signed-off-by: Tony Asleson --- daemons/lvmdbusd/request.py | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/daemons/lvmdbusd/request.py b/daemons/lvmdbusd/request.py index fba65802f..683613119 100644 --- a/daemons/lvmdbusd/request.py +++ b/daemons/lvmdbusd/request.py @@ -64,13 +64,13 @@ class RequestEntry(object): try: result = self.method(*self.arguments) self.register_result(result) - except Exception: + except Exception as e: # Use the request entry to return the result as the client may # have gotten a job by the time we hit an error # Lets get the stacktrace and set that to the error message st = traceback.format_exc() log_error("Exception returned to client: \n%s" % st) - self.register_error(-1, st) + self.register_error(-1, str(e), e) def is_done(self): with self.lock: @@ -87,7 +87,8 @@ class RequestEntry(object): return self._result return '/' - def _reg_ending(self, result, error_rc=0, error=None): + def _reg_ending(self, result, error_rc=0, error_msg=None, + error_exception=None): with self.lock: self.done = True if self.timer_id != -1: @@ -96,7 +97,7 @@ class RequestEntry(object): self._result = result self._rc = error_rc - self._rc_error = error + self._rc_error = error_msg if not self._job: # We finished and there is no job, so return result or error @@ -112,15 +113,23 @@ class RequestEntry(object): self.cb(result) else: if self.cb_error: - self.cb_error(self._rc_error) + if not error_exception: + if not error_msg: + error_exception = Exception( + "An error occurred, but no reason was " + "given, see service logs!") + else: + error_exception = Exception(error_msg) + + self.cb_error(error_exception) else: # We have a job and it's complete, indicate that it's done. # TODO: We need to signal the job is done too. self._job.Complete = True self._job = None - def register_error(self, error_rc, error): - self._reg_ending(None, error_rc, error) + def register_error(self, error_rc, error_message, error_exception): + self._reg_ending(None, error_rc, error_message, error_exception) def register_result(self, result): self._reg_ending(result)