Source code for camelot.model.memento

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"""The ORM part of the classes that store the change history of objects to
the database.  The table defined here is used in :mod:`camelot.core.memento` 
to store the changes.

To prevent this table to be used to store changes, overwrite the 
:meth:`camelot.admin.application_admin.ApplicationAdmin.get_memento` method
the custom `ApplicationAdmin`.
"""

import datetime

import six

from sqlalchemy import schema, orm
from sqlalchemy.types import Unicode, Integer, DateTime, PickleType

from camelot.admin.action import list_filter
from camelot.admin.entity_admin import EntityAdmin
from camelot.admin.object_admin import ObjectAdmin
from camelot.admin.not_editable_admin import not_editable_admin
from camelot.core.orm import Entity, ManyToOne
from camelot.core.utils import ugettext_lazy as _
from camelot.view.controls import delegates
from camelot.types import PrimaryKey

from .authentication import AuthenticationMechanism

[docs]class PreviousAttribute( object ): """Helper class to display previous attributes""" def __init__( self, attribute, previous_value ): self.attribute = attribute self.previous_value = six.text_type( previous_value ) class Admin( ObjectAdmin ): list_display = ['attribute', 'previous_value']
[docs]class Memento( Entity ): """Keeps information on the previous state of objects, to keep track of changes and enable restore to that previous state""" __tablename__ = 'memento' model = schema.Column( Unicode( 256 ), index = True, nullable = False ) primary_key = schema.Column(PrimaryKey(), index=True, nullable=False) creation_date = schema.Column( DateTime(), default = datetime.datetime.now ) authentication = ManyToOne( AuthenticationMechanism, required = True, ondelete = 'restrict', onupdate = 'cascade' ) memento_type = schema.Column( Integer, nullable = False, index = True ) previous_attributes = orm.deferred( schema.Column( PickleType() ) ) @property def previous( self ): previous = self.previous_attributes if previous: return [PreviousAttribute(k,v) for k,v in six.iteritems(previous)] return [] class Admin( EntityAdmin ): verbose_name = _( 'History' ) verbose_name_plural = _( 'History' ) list_display = ['creation_date', 'authentication', 'model', 'primary_key', ] form_display = list_display + ['previous'] list_filter = [list_filter.ComboBoxFilter('model')] field_attributes = {'previous':{'target':PreviousAttribute, 'delegate':delegates.One2ManyDelegate, 'python_type':list} } Admin = not_editable_admin( Admin )