# encoding: utf-8 """Classes and functions for kernel related errors and exceptions. Inheritance diagram: .. inheritance-diagram:: IPython.parallel.error :parts: 3 Authors: * Brian Granger * Min RK """ from __future__ import print_function import sys import traceback __docformat__ = "restructuredtext en" # Tell nose to skip this module __test__ = {} #------------------------------------------------------------------------------- # Copyright (C) 2008-2011 The IPython Development Team # # Distributed under the terms of the BSD License. The full license is in # the file COPYING, distributed as part of this software. #------------------------------------------------------------------------------- #------------------------------------------------------------------------------- # Error classes #------------------------------------------------------------------------------- class IPythonError(Exception): """Base exception that all of our exceptions inherit from. This can be raised by code that doesn't have any more specific information.""" pass # Exceptions associated with the controller objects class ControllerError(IPythonError): pass class ControllerCreationError(ControllerError): pass # Exceptions associated with the Engines class EngineError(IPythonError): pass class EngineCreationError(EngineError): pass class KernelError(IPythonError): pass class NotDefined(KernelError): def __init__(self, name): self.name = name self.args = (name,) def __repr__(self): return '' % self.name __str__ = __repr__ class QueueCleared(KernelError): pass class IdInUse(KernelError): pass class ProtocolError(KernelError): pass class ConnectionError(KernelError): pass class InvalidEngineID(KernelError): pass class NoEnginesRegistered(KernelError): pass class InvalidClientID(KernelError): pass class InvalidDeferredID(KernelError): pass class SerializationError(KernelError): pass class MessageSizeError(KernelError): pass class PBMessageSizeError(MessageSizeError): pass class ResultNotCompleted(KernelError): pass class ResultAlreadyRetrieved(KernelError): pass class ClientError(KernelError): pass class TaskAborted(KernelError): pass class TaskTimeout(KernelError): pass class NotAPendingResult(KernelError): pass class UnpickleableException(KernelError): pass class AbortedPendingDeferredError(KernelError): pass class InvalidProperty(KernelError): pass class MissingBlockArgument(KernelError): pass class StopLocalExecution(KernelError): pass class SecurityError(KernelError): pass class FileTimeoutError(KernelError): pass class TimeoutError(KernelError): pass class UnmetDependency(KernelError): pass class ImpossibleDependency(UnmetDependency): pass class DependencyTimeout(ImpossibleDependency): pass class InvalidDependency(ImpossibleDependency): pass class RemoteError(KernelError): """Error raised elsewhere""" ename=None evalue=None traceback=None engine_info=None def __init__(self, ename, evalue, traceback, engine_info=None): self.ename=ename self.evalue=evalue self.traceback=traceback self.engine_info=engine_info or {} self.args=(ename, evalue) def __repr__(self): engineid = self.engine_info.get('engine_id', ' ') return ""%(engineid, self.ename, self.evalue) def __str__(self): return "%s(%s)" % (self.ename, self.evalue) def render_traceback(self): """render traceback to a list of lines""" return (self.traceback or "No traceback available").splitlines() def _render_traceback_(self): """Special method for custom tracebacks within IPython. This will be called by IPython instead of displaying the local traceback. It should return a traceback rendered as a list of lines. """ return self.render_traceback() def print_traceback(self, excid=None): """print my traceback""" print('\n'.join(self.render_traceback())) class TaskRejectError(KernelError): """Exception to raise when a task should be rejected by an engine. This exception can be used to allow a task running on an engine to test if the engine (or the user's namespace on the engine) has the needed task dependencies. If not, the task should raise this exception. For the task to be retried on another engine, the task should be created with the `retries` argument > 1. The advantage of this approach over our older properties system is that tasks have full access to the user's namespace on the engines and the properties don't have to be managed or tested by the controller. """ class CompositeError(RemoteError): """Error for representing possibly multiple errors on engines""" def __init__(self, message, elist): Exception.__init__(self, *(message, elist)) # Don't use pack_exception because it will conflict with the .message # attribute that is being deprecated in 2.6 and beyond. self.msg = message self.elist = elist self.args = [ e[0] for e in elist ] def _get_engine_str(self, ei): if not ei: return '[Engine Exception]' else: return '[%s:%s]: ' % (ei['engine_id'], ei['method']) def _get_traceback(self, ev): try: tb = ev._ipython_traceback_text except AttributeError: return 'No traceback available' else: return tb def __str__(self): s = str(self.msg) for en, ev, etb, ei in self.elist: engine_str = self._get_engine_str(ei) s = s + '\n' + engine_str + en + ': ' + str(ev) return s def __repr__(self): return "CompositeError(%i)"%len(self.elist) def render_traceback(self, excid=None): """render one or all of my tracebacks to a list of lines""" lines = [] if excid is None: for (en,ev,etb,ei) in self.elist: lines.append(self._get_engine_str(ei)) lines.extend((etb or 'No traceback available').splitlines()) lines.append('') else: try: en,ev,etb,ei = self.elist[excid] except: raise IndexError("an exception with index %i does not exist"%excid) else: lines.append(self._get_engine_str(ei)) lines.extend((etb or 'No traceback available').splitlines()) return lines def print_traceback(self, excid=None): print('\n'.join(self.render_traceback(excid))) def raise_exception(self, excid=0): try: en,ev,etb,ei = self.elist[excid] except: raise IndexError("an exception with index %i does not exist"%excid) else: raise RemoteError(en, ev, etb, ei) def collect_exceptions(rdict_or_list, method='unspecified'): """check a result dict for errors, and raise CompositeError if any exist. Passthrough otherwise.""" elist = [] if isinstance(rdict_or_list, dict): rlist = rdict_or_list.values() else: rlist = rdict_or_list for r in rlist: if isinstance(r, RemoteError): en, ev, etb, ei = r.ename, r.evalue, r.traceback, r.engine_info # Sometimes we could have CompositeError in our list. Just take # the errors out of them and put them in our new list. This # has the effect of flattening lists of CompositeErrors into one # CompositeError if en=='CompositeError': for e in ev.elist: elist.append(e) else: elist.append((en, ev, etb, ei)) if len(elist)==0: return rdict_or_list else: msg = "one or more exceptions from call to method: %s" % (method) # This silliness is needed so the debugger has access to the exception # instance (e in this case) try: raise CompositeError(msg, elist) except CompositeError as e: raise e def wrap_exception(engine_info={}): etype, evalue, tb = sys.exc_info() stb = traceback.format_exception(etype, evalue, tb) exc_content = { 'status' : 'error', 'traceback' : stb, 'ename' : unicode(etype.__name__), 'evalue' : unicode(evalue), 'engine_info' : engine_info } return exc_content def unwrap_exception(content): err = RemoteError(content['ename'], content['evalue'], ''.join(content['traceback']), content.get('engine_info', {})) return err