NDB Metadata Reference

This API is in the google.appengine.ext.ndb.metadata module, typically used via from google.appengine.ext.ndb import metadata.

Functions

get_entity_group_version(key)
Return the version of the entity group containing key. This version is guaranteed to increase on every change to the entity group. The version may increase even in the absence of user-visible changes to the entity group. May return None if the entity group was never written to.

Warning: The behavior of entity group metadata is now different. The entity group version can increase independently of user updates. Previously, the entity group version increased only on user update. To maintain legacy behavior, use the entity group version workaround.

Arguments

key
key for an entity group.
get_namespaces(start=None, end=None)
Returns a list of namespace names.

Arguments

start
Don't return namespace names before this in alphabetical order.
end
Don't return namespace names after this in alphabetical order.
get_kinds(start=None, end=None):
Returns a list of kind names in the current namespace.

Arguments

start
Don't return kind names before this in alphabetical order.
end
Don't return kind names after this in alphabetical order.
get_properties_of_kind(kind, start=None, end=None):
Returns a list of property names for the given kind name in the current namespace.

Arguments

kind
Which kind's properties to list.
start
Don't return property names before this in alphabetical order.
end
Don't return property names after this in alphabetical order.
get_representations_of_kind(kind, start=None, end=None)
Returns a dict mapping property names for the given kind name to lists of representation names such as 'STRING', 'BOOLEAN' or 'INT64'. Only looks in the current namespace. For a complete list of these types, see Representation Types
Returns a list of property names for the given kind name.

Arguments

kind
Which kind's properties to list.
start
Don't return property names before this in alphabetical order.
end
Don't return property names after this in alphabetical order.

Representation Types

Property Class Representation
StringProperty STRING
BooleanProperty BOOLEAN
IntegerProperty INT64
FloatProperty DOUBLE
DateTimeProperty
DateProperty
TimeProperty 		INT64
UserProperty USER
BlobProperty STRING
BlobKeyProperty STRING
TextProperty STRING
GeoPtProperty POINT
GenericProperty (Depends on what value is stored.)
ComputedProperty (Depends on what value is stored.)
JsonProperty STRING
PickleProperty STRING
StructuredProperty (When you get representation types, StructuredProperty properties won't be returned. Instead, it shows values for the subproperties corresponding to their property types.)
LocalStructuredProperty STRING
KeyProperty REFERENCE