4 # Copyright (C) 2006, 2007 Google Inc.
6 # This program is free software; you can redistribute it and/or modify
7 # it under the terms of the GNU General Public License as published by
8 # the Free Software Foundation; either version 2 of the License, or
9 # (at your option) any later version.
11 # This program is distributed in the hope that it will be useful, but
12 # WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 # General Public License for more details.
16 # You should have received a copy of the GNU General Public License
17 # along with this program; if not, write to the Free Software
18 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
22 """Ganeti exception handling"""
25 class GenericError(Exception):
26 """Base exception for Ganeti.
32 class LVMError(GenericError):
33 """LVM-related exception.
35 This exception codifies problems with LVM setup.
41 class LockError(GenericError):
42 """Lock error exception.
44 This signifies problems in the locking subsystem.
50 class HypervisorError(GenericError):
51 """Hypervisor-related exception.
53 This is raised in case we can't communicate with the hypervisor
60 class ProgrammerError(GenericError):
61 """Programming-related error.
63 This is raised in cases we determine that the calling conventions
64 have been violated, meaning we got some desynchronisation between
65 parts of our code. It signifies a real programming bug.
71 class BlockDeviceError(GenericError):
72 """Block-device related exception.
74 This is raised in case we can't setup the instance's block devices
81 class ConfigurationError(GenericError):
82 """Configuration related exception.
84 Things like having an instance with a primary node that doesn't
85 exist in the config or such raise this exception.
91 class RemoteError(GenericError):
92 """Programming-related error on remote call.
94 This is raised when an unhandled error occurs in a call to a
95 remote node. It usually signifies a real programming bug.
101 class SignatureError(GenericError):
102 """Error authenticating a remote message.
104 This is raised when the hmac signature on a message doesn't verify correctly
105 to the message itself. It can happen because of network unreliability or
106 because of spurious traffic.
112 class ParameterError(GenericError):
113 """A passed parameter to a command is invalid.
115 This is raised when the parameter passed to a request function is
116 invalid. Correct code should have verified this before passing the
119 The argument to this exception should be the parameter name.
125 class OpPrereqError(GenericError):
126 """Prerequisites for the OpCode are not fulfilled.
131 class OpExecError(GenericError):
132 """Error during OpCode execution.
137 class OpRetryError(OpExecError):
138 """Error during OpCode execution, action can be retried.
143 class OpCodeUnknown(GenericError):
144 """Unknown opcode submitted.
146 This signifies a mismatch between the definitions on the client and
152 class JobLost(GenericError):
153 """Submitted job lost.
155 The job was submitted but it cannot be found in the current job
161 class ResolverError(GenericError):
162 """Host name cannot be resolved.
164 This is not a normal situation for Ganeti, as we rely on having a
167 The non-resolvable hostname is available as the first element of the
168 args tuple; the other two elements of the tuple are the first two
169 args of the socket.gaierror exception (error code and description).
174 class HooksFailure(GenericError):
175 """A generic hook failure.
177 This signifies usually a setup misconfiguration.
182 class HooksAbort(HooksFailure):
183 """A required hook has failed.
185 This caused an abort of the operation in the initial phase. This
186 exception always has an attribute args which is a list of tuples of:
187 - node: the source node on which this hooks has failed
188 - script: the name of the script which aborted the run
193 class UnitParseError(GenericError):
194 """Unable to parse size unit.
199 class TypeEnforcementError(GenericError):
200 """Unable to enforce data type.
205 class SshKeyError(GenericError):
211 class TagError(GenericError):
212 """Generic tag error.
214 The argument to this exception will show the exact error.
219 class CommandError(GenericError):
220 """External command error.
225 class StorageError(GenericError):
226 """Storage-related exception.
231 class InotifyError(GenericError):
232 """Error raised when there is a failure setting up an inotify watcher.
237 class QuitGanetiException(Exception):
238 """Signal that Ganeti that it must quit.
240 This is not necessarily an error (and thus not a subclass of
241 GenericError), but it's an exceptional circumstance and it is thus
242 treated. This instance should be instantiated with two values. The
243 first one will specify the return code to the caller, and the second
244 one will be the returned result (either as an error or as a normal
245 result). Usually only the leave cluster rpc call should return
246 status True (as there it's expected we quit), every other call will
247 return status False (as a critical error was encountered).
251 # Return a result of "True" to the caller, but quit ganeti afterwards
252 raise QuitGanetiException(True, None)
253 # Send an error to the caller, and quit ganeti
254 raise QuitGanetiException(False, "Fatal safety violation, shutting down")
259 class JobQueueError(GenericError):
265 class JobQueueDrainError(JobQueueError):
266 """Job queue is marked for drain error.
268 This is raised when a job submission attempt is made but the queue
274 class JobQueueFull(JobQueueError):
275 """Job queue full error.
277 Raised when job queue size reached its hard limit.
282 class ConfdFatalError(GenericError):
283 """A fatal failure in Ganeti confd.
285 Events that compromise the ability of confd to proceed further.
286 (for example: inability to load the config file)
291 class ConfdRequestError(GenericError):
292 """A request error in Ganeti confd.
294 Events that should make confd abort the current request and proceed serving
300 class ConfdMagicError(GenericError):
301 """A magic fourcc error in Ganeti confd.
303 Errors processing the fourcc in ganeti confd datagrams.
308 class ConfdClientError(GenericError):
309 """A magic fourcc error in Ganeti confd.
311 Errors in the confd client library.
316 class UdpDataSizeError(GenericError):
317 """UDP payload too big.
322 # errors should be added above
325 def GetErrorClass(name):
326 """Return the class of an exception.
328 Given the class name, return the class itself.
331 @param name: the exception name
333 @return: the actual class, or None if not found
336 item = globals().get(name, None)
338 if not (isinstance(item, type(Exception)) and
339 issubclass(item, GenericError)):
344 def EncodeException(err):
345 """Encodes an exception into a format that L{MaybeRaise} will recognise.
347 The passed L{err} argument will be formatted as a tuple (exception
348 name, arguments) that the MaybeRaise function will recognise.
350 @type err: GenericError child
351 @param err: usually a child of GenericError (but any exception
354 @return: tuple of (exception name, exception arguments)
357 return (err.__class__.__name__, err.args)
360 def MaybeRaise(result):
361 """Is this looks like an encoded Ganeti exception, raise it.
363 This function tries to parse the passed argument and if it looks
364 like an encoding done by EncodeException, it will re-raise it.
368 if (isinstance(result, tlt) and len(result) == 2 and
369 isinstance(result[1], tlt)):
370 # custom ganeti errors
371 err_class = GetErrorClass(result[0])
372 if err_class is not None:
373 raise err_class, tuple(result[1])