Source code for qubesadmin.features

# -*- encoding: utf8 -*-
#
# The Qubes OS Project, http://www.qubes-os.org
#
# Copyright (C) 2017 Marek Marczykowski-Górecki
#                               <[email protected]>
#
# 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/>.

'''VM features interface'''


[docs]class Features(object): '''Manager of the features. Features can have three distinct values: no value (not present in mapping, which is closest thing to :py:obj:`None`), empty string (which is interpreted as :py:obj:`False`) and non-empty string, which is :py:obj:`True`. Anything assigned to the mapping is coerced to strings, however if you assign instances of :py:class:`bool`, they are converted as described above. Be aware that assigning the number `0` (which is considered false in Python) will result in string `'0'`, which is considered true. ''' # pylint: disable=too-few-public-methods def __init__(self, vm): super(Features, self).__init__() self.vm = vm def __delitem__(self, key): self.vm.qubesd_call(self.vm.name, 'admin.vm.feature.Remove', key) def __setitem__(self, key, value): if isinstance(value, bool): # False value needs to be serialized as empty string self.vm.qubesd_call(self.vm.name, 'admin.vm.feature.Set', key, b'1' if value else b'') else: self.vm.qubesd_call(self.vm.name, 'admin.vm.feature.Set', key, str(value).encode()) def __getitem__(self, item): return self.vm.qubesd_call( self.vm.name, 'admin.vm.feature.Get', item).decode('utf-8') def __iter__(self): qubesd_response = self.vm.qubesd_call(self.vm.name, 'admin.vm.feature.List') return iter(qubesd_response.decode('utf-8').splitlines()) keys = __iter__
[docs] def items(self): '''Return iterable of pairs (feature, value)''' for key in self: yield key, self[key]
_NO_DEFAULT = object()
[docs] def get(self, item, default=_NO_DEFAULT): '''Get a feature, return default value if missing.''' try: return self[item] except KeyError: if default is self._NO_DEFAULT: raise return default
[docs] def check_with_template(self, feature, default=_NO_DEFAULT): ''' Check if the vm's template has the specified feature. ''' try: qubesd_response = self.vm.qubesd_call( self.vm.name, 'admin.vm.feature.CheckWithTemplate', feature) return qubesd_response.decode('utf-8') except KeyError: if default is self._NO_DEFAULT: raise return default