# -*- coding: utf-8 -*-
###########################################################################
# Copyright (c), The AiiDA team. All rights reserved. #
# This file is part of the AiiDA code. #
# #
# The code is hosted on GitHub at https://github.com/aiidateam/aiida_core #
# For further information on the license, see the LICENSE.txt file #
# For further information please visit http://www.aiida.net #
###########################################################################
from aiida.common.exceptions import ModificationNotAllowed
from aiida.common.lang import override
from aiida.common.links import LinkType
[docs]class Sealable(object):
# The name of the attribute to indicate if the node is sealed or not
SEALED_KEY = '_sealed'
_updatable_attributes = (SEALED_KEY,)
[docs] def add_link_from(self, src, label=None, link_type=LinkType.UNSPECIFIED):
"""
Add a link from a node
You can use the parameters of the base Node class, in particular the
label parameter to label the link.
:param src: the node to add a link from
:param str label: name of the link
:param link_type: type of the link, must be one of the enum values from
:class:`~aiida.common.links.LinkType`
"""
if self.is_sealed:
raise ModificationNotAllowed('Cannot add a link from a sealed node')
super(Sealable, self).add_link_from(src, label=label, link_type=link_type)
@property
def is_sealed(self):
"""
Returns whether the node is sealed, i.e. whether the sealed attribute has been set to True
"""
return self.get_attr(self.SEALED_KEY, False)
[docs] def seal(self):
"""
Seal the node by setting the sealed attribute to True
"""
if not self.is_sealed:
self._set_attr(self.SEALED_KEY, True)
[docs] @override
def _set_attr(self, key, value, **kwargs):
"""
Set a new attribute
:param key: attribute name
:param value: attribute value
:raise ModificationNotAllowed: if the node is already sealed or if the node is already stored
and the attribute is not updatable
"""
if self.is_sealed:
raise ModificationNotAllowed('Cannot change the attributes of a sealed node')
if self.is_stored and key not in self._updatable_attributes:
raise ModificationNotAllowed('Cannot change the immutable attributes of a stored node')
super(Sealable, self)._set_attr(key, value, stored_check=False, **kwargs)
[docs] @override
def _del_attr(self, key):
"""
Delete an attribute
:param key: attribute name
:raise AttributeError: if key does not exist
:raise ModificationNotAllowed: if the node is already sealed or if the node is already stored
and the attribute is not updatable
"""
if self.is_sealed:
raise ModificationNotAllowed('Cannot change the attributes of a sealed node')
if self.is_stored and key not in self._updatable_attributes:
raise ModificationNotAllowed('Cannot change the immutable attributes of a stored node')
super(Sealable, self)._del_attr(key, stored_check=False)
[docs] @override
def copy(self, include_updatable_attrs=False):
"""
Create a copy of the node minus the updatable attributes
"""
clone = super(Sealable, self).copy()
# Remove the updatable attributes
if not include_updatable_attrs:
for key, value in self._iter_updatable_attributes():
clone._del_attr(key)
return clone
[docs] def _iter_updatable_attributes(self):
"""
Iterate over the updatable attributes and yield key value pairs
"""
for key in list(self._updatable_attributes):
try:
yield (key, self.get_attr(key))
except AttributeError:
pass