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    Class Key (2.21.0) 

      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=...>

    To create a key from a non-default database:

    .. doctest:: key-ctor

    Key('EntityKind', 1234, project=project, database='mydb') <Key('EntityKind', 1234), project=my-special-pony, database=mydb>

    Parameter

    Name
    Description
    path_args
    tuple of string and integer

    May represent a partial (odd length) or full (even length) key path.

    Properties

    database

    Database getter.

    Returns
    Type
    Description
    str
    The database of the current key.

    flat_path

    Getter for the key path as a tuple.

    Returns
    Type
    Description
    tuple of string and integer
    The tuple of elements in the path.

    id

    ID getter. Based on the last element of path.

    Returns
    Type
    Description
    int
    The (integer) ID of the key.

    id_or_name

    Getter. Based on the last element of path.

    Returns
    Type
    Description
    int (if id ) or string (if name )
    The last element of the key's path if it is either an id or a name .

    is_partial

    Boolean indicating if the key has an ID (or name).

    Returns
    Type
    Description
    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.

    Returns
    Type
    Description
    str
    The kind of the current key.

    name

    Name getter. Based on the last element of path.

    Returns
    Type
    Description
    str
    The (string) name of the key.

    namespace

    Namespace getter.

    Returns
    Type
    Description
    str
    The namespace of the current key.

    parent

    The parent of the current key.

    Returns
    Type
    Description
    Key or NoneType
    A new 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.

    Returns
    Type
    Description
    list of dict
    The (key) path of the current key.

    project

    Project getter.

    Returns
    Type
    Description
    str
    The key's project.

    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, database, and namespace.

    (Note that database=None is considered to refer to the default database.)

    Returns
    Type
    Description
    bool
    True if the keys compare equal, else False.

    __hash__

      __hash__ 
 ()

    Hash this key for use in a dictionary lookup.

    Returns
    Type
    Description
    int
    a hash of the key's state.

    __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, database, and namespace.

    (Note that database=None is considered to refer to the default database.)

    Returns
    Type
    Description
    bool
    False if the keys compare equal, else True.

    __repr__

      __repr__ 
 ()

    String representation of this key.

    Includes the project and database, but suppresses them if they are equal to the default values.

    completed_key

      completed_key 
 ( 
 id_or_name 
 )

    Creates new key from existing partial key by adding final ID/name.

    Parameter
    Name
    Description
    id_or_name
    str or integer

    ID or name to be added to the key.

    Exceptions
    Type
    Description
    `ValueError
    if the current key is not partial or if id_or_name is not a string or integer.
    Returns
    Type
    Description
    Key
    A new 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() .

    Parameter
    Name
    Description
    urlsafe
    bytes or unicode

    The base64 encoded (ASCII) string corresponding to a datastore "Key" / "Reference".

    Returns
    Type
    Description
    Key .
    The key corresponding to urlsafe .

    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.

    Parameter
    Name
    Description
    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.

    Returns
    Type
    Description
    bytes
    A bytestring containing the key encoded as URL-safe base64.

    to_protobuf

      to_protobuf 
 ()

    Return a protobuf corresponding to the key.

    Returns
    Type
    Description
    .entity_pb2.Key
    The protobuf representing the key.
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