Class Client (2.19.0) 

Client(project=None, namespace=None, credentials=None, client_info=<google.api_core.gapic_v1.client_info.ClientInfo object>, client_options=None, database=None, _http=None, _use_grpc=None)

Convenience wrapper for invoking APIs/factories w/ a project.

.. doctest::

from google.cloud import datastore client = datastore.Client()

Parameters
Name Description
project str

(Optional) The project to pass to proxied API methods.
namespace str

(Optional) namespace to pass to proxied API methods.
credentials google.auth.credentials.Credentials

(Optional) The OAuth2 Credentials to use for this client. If not passed (and if no _http object is passed), falls back to the default inferred from the environment.
client_info google.api_core.gapic_v1.client_info.ClientInfo or google.api_core.client_info.ClientInfo

(Optional) The client info used to send a user-agent string along with API requests. If None, then default info will be used. Generally, you only need to set this if you're developing your own library or partner tool.
client_options google.api_core.client_options.ClientOptions or dict

(Optional) Client options used to set user options on the client. API Endpoint should be set through client_options.
_http requests.Session

(Optional) HTTP object to make requests. Can be any object that defines request() with the same interface as requests.Session.request. If not passed, an _http object is created that is bound to the credentials for the current object. This parameter should be considered private, and could change in the future.
_use_grpc bool

(Optional) Explicitly specifies whether to use the gRPC transport (via GAX) or HTTP. If unset, falls back to the GOOGLE_CLOUD_DISABLE_GRPC environment variable. This parameter should be considered private, and could change in the future.
database str

(Optional) database to pass to proxied API methods.

Properties

base_url

Getter for API base URL.

current_batch

Currently-active batch.

Returns
Type Description
Batch, or an object implementing its API, or NoneType (if no batch is active). The batch/transaction at the top of the batch stack.

current_transaction

Currently-active transaction.

Returns
Type Description
Transaction, or an object implementing its API, or NoneType (if no transaction is active). The transaction at the top of the batch stack.

database

Getter for database

Methods

aggregation_query

aggregation_query(query)

Proxy to xref_AggregationQuery.

Using aggregation_query to count over a query:

.. testsetup:: aggregation_query

import uuid

from google.cloud import datastore
from <xref uid="google.cloud.datastore.aggregation">google.cloud.datastore.aggregation</xref> import CountAggregation

unique = str(uuid.uuid4())[0:8]
client = datastore.Client(namespace='ns{}'.format(unique))

def do_something_with(entity):
    pass

.. doctest:: aggregation_query

>>> query = client.query(kind='MyKind')
>>> aggregation_query = client.aggregation_query(query)
>>> aggregation_query.count(alias='total')
<<xref uid="google.cloud.datastore.aggregation.AggregationQuery">google.cloud.datastore.aggregation.AggregationQuery</xref> object at ...>
>>> aggregation_query.fetch()
<<xref uid="google.cloud.datastore.aggregation.AggregationResultIterator">google.cloud.datastore.aggregation.AggregationResultIterator</xref> object at ...>

Adding an aggregation to the aggregation_query

.. doctest:: aggregation_query

>>> query = client.query(kind='MyKind')
>>> aggregation_query.add_aggregation(CountAggregation(alias='total'))
>>> aggregation_query.fetch()
<<xref uid="google.cloud.datastore.aggregation.AggregationResultIterator">google.cloud.datastore.aggregation.AggregationResultIterator</xref> object at ...>

Adding multiple aggregations to the aggregation_query

.. doctest:: aggregation_query

>>> query = client.query(kind='MyKind')
>>> total_count = CountAggregation(alias='total')
>>> all_count = CountAggregation(alias='all')
>>> aggregation_query.add_aggregations([total_count, all_count])
>>> aggregation_query.fetch()
<<xref uid="google.cloud.datastore.aggregation.AggregationResultIterator">google.cloud.datastore.aggregation.AggregationResultIterator</xref> object at ...>

Using the aggregation_query iterator

.. doctest:: aggregation_query

>>> query = client.query(kind='MyKind')
>>> aggregation_query = client.aggregation_query(query)
>>> aggregation_query.count(alias='total')
<<xref uid="google.cloud.datastore.aggregation.AggregationQuery">google.cloud.datastore.aggregation.AggregationQuery</xref> object at ...>
>>> aggregation_query_iter = aggregation_query.fetch()
>>> for aggregation_result in aggregation_query_iter:
...     do_something_with(aggregation_result)

or manually page through results

.. doctest:: aggregation_query

>>> aggregation_query_iter = aggregation_query.fetch()
>>> pages = aggregation_query_iter.pages
>>>
>>> first_page = next(pages)
>>> first_page_entities = list(first_page)
>>> aggregation_query_iter.next_page_token is None
True
Returns
Type Description
AggregationQuery An AggregationQuery object.

allocate_ids

allocate_ids(incomplete_key, num_ids, retry=None, timeout=None)

Allocate a list of IDs from a partial key.

Parameters
Name Description
incomplete_key Key

Partial key to use as base for allocated IDs.
num_ids int

The number of IDs to allocate.
retry google.api_core.retry.Retry

A retry object used to retry requests. If None is specified, requests will be retried using a default configuration.
timeout float

Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt.
Exceptions
Type Description
`ValueError if incomplete_key is not a partial key.
Returns
Type Description
list of Key The (complete) keys allocated with incomplete_key as root.

batch

batch()

Proxy to Batch.

delete

delete(key, retry=None, timeout=None)

Delete the key in the Cloud Datastore.

Parameters
Name Description
key Key, Entity

The key to be deleted from the datastore.
retry google.api_core.retry.Retry

A retry object used to retry requests. If None is specified, requests will be retried using a default configuration. Only meaningful outside of another batch / transaction.
timeout float

Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt. Only meaningful outside of another batch / transaction.

delete_multi

delete_multi(keys, retry=None, timeout=None)

Delete keys from the Cloud Datastore.

Parameters
Name Description
keys list of Key, Entity

The keys to be deleted from the Datastore.
retry google.api_core.retry.Retry

A retry object used to retry requests. If None is specified, requests will be retried using a default configuration. Only meaningful outside of another batch / transaction.
timeout float

Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt. Only meaningful outside of another batch / transaction.

entity

entity(key=None, exclude_from_indexes=())

Proxy to Entity.

get

get(
    key,
    missing=None,
    deferred=None,
    transaction=None,
    eventual=False,
    retry=None,
    timeout=None,
    read_time=None,
)

Retrieve an entity from a single key (if it exists).

Parameters
Name Description
key Key

The key to be retrieved from the datastore.
missing list

(Optional) If a list is passed, the key-only entities returned by the backend as "missing" will be copied into it.
deferred list

(Optional) If a list is passed, the keys returned by the backend as "deferred" will be copied into it.
transaction Transaction

(Optional) Transaction to use for read consistency. If not passed, uses current transaction, if set.
eventual bool

(Optional) Defaults to strongly consistent (False). Setting True will use eventual consistency, but cannot be used inside a transaction or with read_time, or will raise ValueError.
retry google.api_core.retry.Retry

A retry object used to retry requests. If None is specified, requests will be retried using a default configuration.
timeout float

Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt.
read_time datetime

Read the entity from the specified time (may be null). Cannot be used with eventual consistency or inside a transaction, or will raise ValueError. This feature is in private preview.
Exceptions
Type Description
`ValueError if more than one of eventual==True, transaction, and read_time is specified.
Returns
Type Description
Entity or NoneType The requested entity if it exists.

get_multi

get_multi(
    keys,
    missing=None,
    deferred=None,
    transaction=None,
    eventual=False,
    retry=None,
    timeout=None,
    read_time=None,
)

Retrieve entities, along with their attributes.

Parameters
Name Description
keys list of Key

The keys to be retrieved from the datastore.
missing list

(Optional) If a list is passed, the key-only entities returned by the backend as "missing" will be copied into it. If the list is not empty, an error will occur.
deferred list

(Optional) If a list is passed, the keys returned by the backend as "deferred" will be copied into it. If the list is not empty, an error will occur.
transaction Transaction

(Optional) Transaction to use for read consistency. If not passed, uses current transaction, if set.
eventual bool

(Optional) Defaults to strongly consistent (False). Setting True will use eventual consistency, but cannot be used inside a transaction or will raise ValueError.
retry google.api_core.retry.Retry

A retry object used to retry requests. If None is specified, requests will be retried using a default configuration.
timeout float

Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt.
read_time datetime

(Optional) Read time to use for read consistency. This feature is in private preview.
Exceptions
Type Description
`ValueError if one or more of keys has a project which does not match our project; or if more than one of eventual==True, transaction, and read_time is specified.
Returns
Type Description
list of Entity The requested entities.

key

key(*path_args, **kwargs)

Proxy to Key.

Passes our project and our database.

put

put(entity, retry=None, timeout=None)

Save an entity in the Cloud Datastore.

Parameters
Name Description
entity Entity

The entity to be saved to the datastore.
retry google.api_core.retry.Retry

A retry object used to retry requests. If None is specified, requests will be retried using a default configuration. Only meaningful outside of another batch / transaction.
timeout float

Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt. Only meaningful outside of another batch / transaction.

put_multi

put_multi(entities, retry=None, timeout=None)

Save entities in the Cloud Datastore.

Parameters
Name Description
entities list of Entity

The entities to be saved to the datastore.
retry google.api_core.retry.Retry

A retry object used to retry requests. If None is specified, requests will be retried using a default configuration. Only meaningful outside of another batch / transaction.
timeout float

Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt. Only meaningful outside of another batch / transaction.
Exceptions
Type Description
`ValueError if entities is a single entity.

query

query(**kwargs)

Proxy to xref_Query.

Passes our project.

Using query to search a datastore:

.. testsetup:: query

import uuid

from google.cloud import datastore

unique = str(uuid.uuid4())[0:8]
client = datastore.Client(namespace='ns{}'.format(unique))

def do_something_with(entity):
    pass

.. doctest:: query

>>> query = client.query(kind='MyKind')
>>> query.add_filter('property', '=', 'val')
<<xref uid="google.cloud.datastore.query.Query">google.cloud.datastore.query.Query</xref> object at ...>

Using the query iterator

.. doctest:: query

>>> filters = [('property', '=', 'val')]
>>> query = client.query(kind='MyKind', filters=filters)
>>> query_iter = query.fetch()
>>> for entity in query_iter:
...     do_something_with(entity)

or manually page through results

.. doctest:: query

>>> query_iter = query.fetch()
>>> pages = query_iter.pages
>>>
>>> first_page = next(pages)
>>> first_page_entities = list(first_page)
>>> query_iter.next_page_token is None
True
Returns
Type Description
Query A query object.

reserve_ids

reserve_ids(complete_key, num_ids, retry=None, timeout=None)

Reserve a list of IDs sequentially from a complete key.

DEPRECATED. Alias for reserve_ids_sequential.

Please use either reserve_ids_multi (recommended) or reserve_ids_sequential.

reserve_ids_multi

reserve_ids_multi(complete_keys, retry=None, timeout=None)

Reserve IDs from a list of complete keys.

Parameters
Name Description
complete_keys list of Key

Complete keys for which to reserve IDs.
retry google.api_core.retry.Retry

A retry object used to retry requests. If None is specified, requests will be retried using a default configuration.
timeout float

Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt.
Exceptions
Type Description
`ValueError if any of complete_keys is not a Complete key.
Returns
Type Description
class:NoneType None

reserve_ids_sequential

reserve_ids_sequential(complete_key, num_ids, retry=None, timeout=None)

Reserve a list of IDs sequentially from a complete key.

This will reserve the key passed as complete_key as well as additional keys derived by incrementing the last ID in the path of complete_key sequentially to obtain the number of keys specified in num_ids.

Parameters
Name Description
complete_key Key

Complete key to use as base for reserved IDs. Key must use a numeric ID and not a string name.
num_ids int

The number of IDs to reserve.
retry google.api_core.retry.Retry

A retry object used to retry requests. If None is specified, requests will be retried using a default configuration.
timeout float

Time, in seconds, to wait for the request to complete. Note that if retry is specified, the timeout applies to each individual attempt.
Exceptions
Type Description
`ValueError if complete_key is not a Complete key.
Returns
Type Description
class:NoneType None

transaction

transaction(**kwargs)

Proxy to xref_Transaction.