core-admin-client/qubesadmin/exc.py

# -*- encoding: utf8 -*-
#
# The Qubes OS Project, http://www.qubes-os.org
#
# Copyright (C) 2017 Marek Marczykowski-Górecki
#                               <marmarek@invisiblethingslab.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with this program; if not, see <http://www.gnu.org/licenses/>.

'''Exception hierarchy.'''


class QubesException(Exception):
    '''Base exception for all Qubes-related errors.'''
    def __init__(self, message_format, *args, **kwargs):
        # TODO: handle translations
        super(QubesException, self).__init__(
            message_format % tuple(int(d) if d.isdigit() else d for d in args),
            **kwargs)


class QubesVMNotFoundError(QubesException, KeyError):
    '''Domain cannot be found in the system'''

    def __str__(self):
        # KeyError overrides __str__ method
        return QubesException.__str__(self)


class QubesVMError(QubesException):
    '''Some problem with domain state.'''


class QubesVMNotStartedError(QubesVMError):
    '''Domain is not started.

    This exception is thrown when machine is halted, but should be started
    (that is, either running or paused).
    '''


class QubesVMNotRunningError(QubesVMNotStartedError):
    '''Domain is not running.

    This exception is thrown when machine should be running but is either
    halted or paused.
    '''


class QubesVMNotPausedError(QubesVMNotStartedError):
    '''Domain is not paused.

    This exception is thrown when machine should be paused, but is not.
    '''


class QubesVMNotSuspendedError(QubesVMError):
    '''Domain is not suspended.

    This exception is thrown when machine should be suspended but is either
    halted or running.
    '''


class QubesVMNotHaltedError(QubesVMError):
    '''Domain is not halted.

    This exception is thrown when machine should be halted, but is not (either
    running or paused).
    '''


class QubesVMShutdownTimeout(QubesVMError):
    ''' Domain shutdown haven't completed in expected timeframe'''


class QubesNoTemplateError(QubesVMError):
    '''Cannot start domain, because there is no template'''


class QubesVMInUseError(QubesVMError):
    '''VM is in use, cannot remove.'''


class QubesValueError(QubesException, ValueError):
    '''Cannot set some value, because it is invalid, out of bounds, etc.'''


class QubesPropertyValueError(QubesValueError):
    '''Cannot set value of qubes.property, because user-supplied value is wrong.
    '''


class QubesNoSuchPropertyError(QubesException, AttributeError):
    '''Requested property does not exist
    '''


class QubesNotImplementedError(QubesException, NotImplementedError):
    '''Thrown at user when some feature is not implemented'''


class BackupCancelledError(QubesException):
    '''Thrown at user when backup was manually cancelled'''


class BackupAlreadyRunningError(QubesException):
    '''Thrown at user when they try to run the same backup twice at
    the same time'''


class QubesMemoryError(QubesException, MemoryError):
    '''Cannot start domain, because not enough memory is available'''


class QubesFeatureNotFoundError(QubesException, KeyError):
    '''Feature not set for a given domain'''
    def __str__(self):
        # KeyError overrides __str__ method
        return QubesException.__str__(self)


class QubesTagNotFoundError(QubesException, KeyError):
    '''Tag not set for a given domain'''
    def __str__(self):
        # KeyError overrides __str__ method
        return QubesException.__str__(self)


class StoragePoolException(QubesException):
    ''' A general storage exception '''


class QubesDaemonCommunicationError(QubesException, IOError):
    '''Error while communicating with qubesd, may mean insufficient
    permissions as well'''


class DeviceAlreadyAttached(QubesException, KeyError):
    '''Trying to attach already attached device'''
    def __str__(self):
        # KeyError overrides __str__ method
        return QubesException.__str__(self)


class BackupRestoreError(QubesException):
    '''Restoring a backup failed'''
    def __init__(self, msg, backup_log=None):
        super(BackupRestoreError, self).__init__(msg)
        self.backup_log = backup_log

# pylint: disable=too-many-ancestors
class QubesDaemonAccessError(QubesDaemonCommunicationError):
    '''Got empty response from qubesd. This can be lack of permission,
    or some server-side issue.'''


class QubesPropertyAccessError(QubesDaemonAccessError, AttributeError):
    '''Failed to read/write property value, cause is unknown (insufficient
    permissions, no such property, invalid value, other)'''
    def __init__(self, prop):
        super(QubesPropertyAccessError, self).__init__(
            'Failed to access \'%s\' property' % prop)

# legacy name
QubesDaemonNoResponseError = QubesDaemonAccessError