API docs for “vmc.contrib.axiom.item”

Function	normalize	Turn a fully-qualified Python name into a string usable as part of a
Class	NoInheritance	Inheritance is as-yet unsupported by XAtop.
Class	NotInStore	Undocumented
Class	CantInstantiateItem	You can't instantiate Item directly. Make a subclass.
Class	MetaItem	Simple metaclass for Item that adds Item (and its subclasses) to
Function	noop	Undocumented
Function	serviceSpecialCase	Undocumented
Class	Empowered	No class docstring; 4/5 methods documented
Function	transacted	Return a callable which will invoke `func` in a transaction using the
Function	dependentItems	Collect all the items that should be deleted when an item or items
Function	allowDeletion	Returns a `bool` indicating whether deletion of an item or items of a
Class	Item	No class docstring; 3/7 class methods, 11/18 methods documented
Class	Placeholder	Wrap an existing `Item` type to provide a different name for it.
Function	declareLegacyItem	Generate a dummy subclass of Item that will have the given attributes,

def transacted(func):

Return a callable which will invoke func in a transaction using the store attribute of the first parameter passed to it. Typically this is used to create Item methods which are automatically run in a transaction.

The attributes of the returned callable will resemble those of func as closely as twisted.python.util.mergeFunctionMetadata can make them.

def dependentItems(store, tableClass, comparisonFactory):

Collect all the items that should be deleted when an item or items of a particular item type are deleted.

Parameters	tableClass	An `Item` subclass.
	comparison	A one-argument callable taking an attribute and returning an `iaxiom.IComparison` describing the items to collect.
Returns	An iterable of items to delete.

def allowDeletion(store, tableClass, comparisonFactory):

Returns a bool indicating whether deletion of an item or items of a particular item type should be allowed to proceed.

Parameters	tableClass	An `Item` subclass.
	comparison	A one-argument callable taking an attribute and returning an `iaxiom.IComparison` describing the items to collect.
Returns	A `bool` indicating whether deletion should be allowed.

def declareLegacyItem(typeName, schemaVersion, attributes, dummyBases=()):

Generate a dummy subclass of Item that will have the given attributes, and the base Item methods, but no methods of its own. This is for use with upgrading.

Parameters	typeName	a string, the Axiom TypeName to have attributes for.
	schemaVersion	an int, the (old) version of the schema this is a proxy for.
	attributes	a dict mapping {columnName: attr instance} describing the schema of `typeName` at `schemaVersion`.
	dummyBases	a sequence of 4-tuples of (baseTypeName, baseSchemaVersion, baseAttributes, baseBases) representing the dummy bases of this legacy class.

Module v.c.a.item