class ObjectListBase(object):
"""Mixin class for lists of objects.
This mixin class can be added as a base class for an object that
is implementing a list of objects. It adds a single field of 'objects',
which is the list store, and behaves like a list itself. It supports
serialization of the list of objects automatically.
"""
fields = {
'objects': fields.ListOfObjectsField('VersionedObject'),
}
# This is a dictionary of my_version:child_version mappings so that
# we can support backleveling our contents based on the version
# requested of the list object.
child_versions = {}
def __init__(self, *args, **kwargs):
super(ObjectListBase, self).__init__(*args, **kwargs)
if 'objects' not in kwargs:
self.objects = []
self._changed_fields.discard('objects')
def __iter__(self):
"""List iterator interface."""
return iter(self.objects)
def __len__(self):
"""List length."""
return len(self.objects)
def __getitem__(self, index):
"""List index access."""
if isinstance(index, slice):
new_obj = self.__class__()
new_obj.objects = self.objects[index]
# NOTE(danms): We must be mixed in with a VersionedObject!
new_obj.obj_reset_changes()
new_obj._context = self._context
return new_obj
return self.objects[index]
def __contains__(self, value):
"""List membership test."""
return value in self.objects
def count(self, value):
"""List count of value occurrences."""
return self.objects.count(value)
def index(self, value):
"""List index of value."""
return self.objects.index(value)
def sort(self, cmp=None, key=None, reverse=False):
self.objects.sort(cmp=cmp, key=key, reverse=reverse)
def obj_make_compatible(self, primitive, target_version):
primitives = primitive['objects']
child_target_version = self.child_versions.get(target_version, '1.0')
for index, item in enumerate(self.objects):
self.objects[index].obj_make_compatible(
primitives[index]['versioned_object.data'],
child_target_version)
primitives[index][
'versioned_object.version'] = child_target_version
def obj_what_changed(self):
changes = set(self._changed_fields)
for child in self.objects:
if child.obj_what_changed():
changes.add('objects')
return changes
class MyObj(base.VersionedPersistentObject, base.VersionedObject,
base.VersionedObjectDictCompat):
VERSION = '1.6'
fields = {
'foo': fields.Field(fields.Integer(), default=1),
'bar': fields.Field(fields.String()),
'missing': fields.Field(fields.String()),
'readonly': fields.Field(fields.Integer(), read_only=True),
'rel_object': fields.ObjectField('MyOwnedObject', nullable=True),
'rel_objects': fields.ListOfObjectsField('MyOwnedObject',
nullable=True),
}
@staticmethod
def _from_db_object(context, obj, db_obj):
self = MyObj()
self.foo = db_obj['foo']
self.bar = db_obj['bar']
self.missing = db_obj['missing']
self.readonly = 1
return self
def obj_load_attr(self, attrname):
setattr(self, attrname, 'loaded!')
@base.remotable_classmethod
def query(cls, context):
obj = cls(context=context, foo=1, bar='bar')
obj.obj_reset_changes()
return obj
@base.remotable
def marco(self, context):
return 'polo'
@base.remotable
def _update_test(self, context):
if context.tenant == 'alternate':
self.bar = 'alternate-context'
else:
self.bar = 'updated'
@base.remotable
def save(self, context):
self.obj_reset_changes()
@base.remotable
def refresh(self, context):
self.foo = 321
self.bar = 'refreshed'
self.obj_reset_changes()
@base.remotable
def modify_save_modify(self, context):
self.bar = 'meow'
self.save()
self.foo = 42
self.rel_object = MyOwnedObject(baz=42)
def obj_make_compatible(self, primitive, target_version):
super(MyObj, self).obj_make_compatible(primitive, target_version)
# NOTE(danms): Simulate an older version that had a different
# format for the 'bar' attribute
if target_version == '1.1' and 'bar' in primitive:
primitive['bar'] = 'old%s' % primitive['bar']
class Foo(base.ObjectListBase, base.VersionedObject):
fields = {'objects': fields.ListOfObjectsField('Bar')}
class MyList(base.ObjectListBase, base.VersionedObject):
fields = {'objects': fields.ListOfObjectsField('MyObj')}