Key
(
*
path_args
,
**
kwargs
)
An immutable representation of a datastore Key.
.. testsetup:: key-ctor
from google.cloud import datastore
project = 'my-special-pony' client = datastore.Client(project=project) Key = datastore.Key
parent_key = client.key('Parent', 'foo')
To create a basic key directly:
.. doctest:: key-ctor
Key('EntityKind', 1234, project=project) <Key('EntityKind', 1234), project=...> Key('EntityKind', 'foo', project=project) <Key('EntityKind', 'foo'), project=...>
Though typical usage comes via the xref_key factory:
.. doctest:: key-ctor
client.key('EntityKind', 1234) <Key('EntityKind', 1234), project=...> client.key('EntityKind', 'foo') <Key('EntityKind', 'foo'), project=...>
To create a key with a parent:
.. doctest:: key-ctor
client.key('Parent', 'foo', 'Child', 1234) <Key('Parent', 'foo', 'Child', 1234), project=...> client.key('Child', 1234, parent=parent_key) <Key('Parent', 'foo', 'Child', 1234), project=...>
To create a partial key:
.. doctest:: key-ctor
client.key('Parent', 'foo', 'Child') <Key('Parent', 'foo', 'Child'), project=...>
Parameter
path_args
tuple of string and integer
May represent a partial (odd length) or full (even length) key path.
Properties
flat_path
Getter for the key path as a tuple.
tuple of string and integer
id
ID getter. Based on the last element of path.
int
id_or_name
Getter. Based on the last element of path.
int (if id
) or string (if name
)
id
or a name
.is_partial
Boolean indicating if the key has an ID (or name).
bool
True
if the last element of the key's path does not have an id
or a name
.kind
Kind getter. Based on the last element of path.
str
name
Name getter. Based on the last element of path.
str
namespace
Namespace getter.
str
parent
The parent of the current key.
Key
or NoneType
Key
instance, whose path consists of all but the last element of current path. If the current key has only one path element, returns None
.path
Path getter.
Returns a copy so that the key remains immutable.
list
of dict
project
Project getter.
str
Methods
__eq__
__eq__
(
other
)
Compare two keys for equality.
Incomplete keys never compare equal to any other key.
Completed keys compare equal if they have the same path, project, and namespace.
bool
__hash__
__hash__
()
Hash a keys for use in a dictionary lookp.
int
__ne__
__ne__
(
other
)
Compare two keys for inequality.
Incomplete keys never compare equal to any other key.
Completed keys compare equal if they have the same path, project, and namespace.
bool
completed_key
completed_key
(
id_or_name
)
Creates new key from existing partial key by adding final ID/name.
id_or_name
str or integer
ID or name to be added to the key.
`ValueError
id_or_name
is not a string or integer.Key
instance with the same data as the current one and an extra ID or name added.from_legacy_urlsafe
from_legacy_urlsafe
(
urlsafe
)
Convert urlsafe string to xref_Key.
This is intended to work with the "legacy" representation of a
datastore "Key" used within Google App Engine (a so-called
"Reference"). This assumes that urlsafe
was created within an App
Engine app via something like ndb.Key(...).urlsafe()
.
urlsafe
bytes or unicode
The base64 encoded (ASCII) string corresponding to a datastore "Key" / "Reference".
to_legacy_urlsafe
to_legacy_urlsafe
(
location_prefix
=
None
)
Convert to a base64 encode urlsafe string for App Engine.
This is intended to work with the "legacy" representation of a
datastore "Key" used within Google App Engine (a so-called
"Reference"). The returned string can be used as the urlsafe
argument to ndb.Key(urlsafe=...)
. The base64 encoded values
will have padding removed.
location_prefix
str
The location prefix of an App Engine project ID. Often this value is 's ', but may also be 'e
', or other location prefixes currently unknown.
bytes
to_protobuf
to_protobuf
()
Return a protobuf corresponding to the key.
.entity_pb2.Key
