def next_page(self):
"""Fetch a single "page" of query results.
Low-level API for fine control: the more convenient API is
to iterate on the current Iterator.
:rtype: tuple, (entities, more_results, cursor)
"""
pb = _pb_from_query(self._query)
start_cursor = self._start_cursor
if start_cursor is not None:
pb.start_cursor = base64.b64decode(start_cursor)
end_cursor = self._end_cursor
if end_cursor is not None:
pb.end_cursor = base64.b64decode(end_cursor)
if self._limit is not None:
pb.limit = self._limit
pb.offset = self._offset
transaction = Transaction.current()
query_results = self._connection.run_query(
query_pb=pb,
dataset_id=self._query.dataset_id,
namespace=self._query.namespace,
transaction_id=transaction and transaction.id,
)
# NOTE: `query_results` contains an extra value that we don't use,
# namely `skipped_results`.
#
# NOTE: The value of `more_results` is not currently useful because
# the back-end always returns an enum
# value of MORE_RESULTS_AFTER_LIMIT even if there are no more
# results. See
# https://github.com/GoogleCloudPlatform/gcloud-python/issues/280
# for discussion.
entity_pbs, cursor_as_bytes, more_results_enum = query_results[:3]
self._start_cursor = base64.b64encode(cursor_as_bytes)
self._end_cursor = None
if more_results_enum == self._NOT_FINISHED:
self._more_results = True
elif more_results_enum in self._FINISHED:
self._more_results = False
else:
raise ValueError('Unexpected value returned for `more_results`.')
self._page = [
helpers.entity_from_protobuf(entity) for entity in entity_pbs
]
return self._page, self._more_results, self._start_cursor
def next_page(self):
"""Fetch a single "page" of query results.
Low-level API for fine control: the more convenient API is
to iterate on the current Iterator.
:rtype: tuple, (entities, more_results, cursor)
"""
pb = _pb_from_query(self._query)
start_cursor = self._start_cursor
if start_cursor is not None:
pb.start_cursor = base64.b64decode(start_cursor)
end_cursor = self._end_cursor
if end_cursor is not None:
pb.end_cursor = base64.b64decode(end_cursor)
if self._limit is not None:
pb.limit = self._limit
pb.offset = self._offset
transaction = Transaction.current()
query_results = self._connection.run_query(
query_pb=pb,
dataset_id=self._query.dataset_id,
namespace=self._query.namespace,
transaction_id=transaction and transaction.id,
)
# NOTE: `query_results` contains an extra value that we don't use,
# namely `skipped_results`.
#
# NOTE: The value of `more_results` is not currently useful because
# the back-end always returns an enum
# value of MORE_RESULTS_AFTER_LIMIT even if there are no more
# results. See
# https://github.com/GoogleCloudPlatform/gcloud-python/issues/280
# for discussion.
entity_pbs, cursor_as_bytes, more_results_enum = query_results[:3]
self._start_cursor = base64.b64encode(cursor_as_bytes)
self._end_cursor = None
if more_results_enum == self._NOT_FINISHED:
self._more_results = True
elif more_results_enum in self._FINISHED:
self._more_results = False
else:
raise ValueError('Unexpected value returned for `more_results`.')
self._page = [
helpers.entity_from_protobuf(entity)
for entity in entity_pbs]
return self._page, self._more_results, self._start_cursor
def get(keys, missing=None, deferred=None, connection=None):
"""Retrieves entities, along with their attributes.
:type keys: list of :class:`gcloud.datastore.key.Key`
:param keys: The keys to be retrieved from the datastore.
:type missing: an empty list or None.
:param missing: If a list is passed, the key-only entities returned
by the backend as "missing" will be copied into it.
Use only as a keyword param.
:type deferred: an empty list or None.
:param deferred: If a list is passed, the keys returned
by the backend as "deferred" will be copied into it.
Use only as a keyword param.
:type connection: :class:`gcloud.datastore.connection.Connection`
:param connection: Optional. The connection used to connect to datastore.
:rtype: list of :class:`gcloud.datastore.entity.Entity`
:returns: The requested entities.
"""
if not keys:
return []
connection = _require_connection(connection)
dataset_id = _get_dataset_id_from_keys(keys)
transaction = Transaction.current()
entity_pbs = connection.lookup(
dataset_id=dataset_id,
key_pbs=[k.to_protobuf() for k in keys],
missing=missing, deferred=deferred,
transaction_id=transaction and transaction.id,
)
if missing is not None:
missing[:] = [
helpers.entity_from_protobuf(missed_pb)
for missed_pb in missing]
if deferred is not None:
deferred[:] = [
helpers.key_from_protobuf(deferred_pb)
for deferred_pb in deferred]
entities = []
for entity_pb in entity_pbs:
entities.append(helpers.entity_from_protobuf(entity_pb))
return entities
def get_multi(keys, missing=None, deferred=None,
connection=None, dataset_id=None):
"""Retrieves entities, along with their attributes.
:type keys: list of :class:`gcloud.datastore.key.Key`
:param keys: The keys to be retrieved from the datastore.
:type missing: an empty list or None.
:param missing: If a list is passed, the key-only entities returned
by the backend as "missing" will be copied into it.
Use only as a keyword param.
:type deferred: an empty list or None.
:param deferred: If a list is passed, the keys returned
by the backend as "deferred" will be copied into it.
Use only as a keyword param.
:type connection: :class:`gcloud.datastore.connection.Connection`
:param connection: Optional. The connection used to connect to datastore.
If not passed, inferred from the environment.
:type dataset_id: :class:`gcloud.datastore.connection.Connection`
:param dataset_id: Optional. The dataset ID used to connect to datastore.
If not passed, inferred from the environment.
:rtype: list of :class:`gcloud.datastore.entity.Entity`
:returns: The requested entities.
:raises: EnvironmentError if ``connection`` or ``dataset_id`` not passed,
and cannot be inferred from the environment. ValueError if
one or more of ``keys`` has a dataset ID which does not match
the passed / inferred dataset ID.
"""
if not keys:
return []
connection = _require_connection(connection)
dataset_id = _require_dataset_id(dataset_id, keys[0])
if list(set([key.dataset_id for key in keys])) != [dataset_id]:
raise ValueError('Keys do not match dataset ID')
transaction = Transaction.current()
entity_pbs = _extended_lookup(
connection,
dataset_id=dataset_id,
key_pbs=[k.to_protobuf() for k in keys],
missing=missing,
deferred=deferred,
transaction_id=transaction and transaction.id,
)
if missing is not None:
missing[:] = [
helpers.entity_from_protobuf(missed_pb)
for missed_pb in missing]
if deferred is not None:
deferred[:] = [
helpers.key_from_protobuf(deferred_pb)
for deferred_pb in deferred]
entities = []
for entity_pb in entity_pbs:
entities.append(helpers.entity_from_protobuf(entity_pb))
return entities
def get(keys, missing=None, deferred=None, connection=None, dataset_id=None):
"""Retrieves entities, along with their attributes.
:type keys: list of :class:`gcloud.datastore.key.Key`
:param keys: The keys to be retrieved from the datastore.
:type missing: an empty list or None.
:param missing: If a list is passed, the key-only entities returned
by the backend as "missing" will be copied into it.
Use only as a keyword param.
:type deferred: an empty list or None.
:param deferred: If a list is passed, the keys returned
by the backend as "deferred" will be copied into it.
Use only as a keyword param.
:type connection: :class:`gcloud.datastore.connection.Connection`
:param connection: Optional. The connection used to connect to datastore.
If not passed, inferred from the environment.
:type dataset_id: :class:`gcloud.datastore.connection.Connection`
:param dataset_id: Optional. The dataset ID used to connect to datastore.
If not passed, inferred from the environment.
:rtype: list of :class:`gcloud.datastore.entity.Entity`
:returns: The requested entities.
:raises: EnvironmentError if ``connection`` or ``dataset_id`` not passed,
and cannot be inferred from the environment. ValueError if
one or more of ``keys`` has a dataset ID which does not match
the passed / inferred dataset ID.
"""
if not keys:
return []
connection = _require_connection(connection)
dataset_id = _require_dataset_id(dataset_id, keys[0])
if list(set([key.dataset_id for key in keys])) != [dataset_id]:
raise ValueError('Keys do not match dataset ID')
transaction = Transaction.current()
entity_pbs = _extended_lookup(
connection,
dataset_id=dataset_id,
key_pbs=[k.to_protobuf() for k in keys],
missing=missing,
deferred=deferred,
transaction_id=transaction and transaction.id,
)
if missing is not None:
missing[:] = [
helpers.entity_from_protobuf(missed_pb)
for missed_pb in missing]
if deferred is not None:
deferred[:] = [
helpers.key_from_protobuf(deferred_pb)
for deferred_pb in deferred]
entities = []
for entity_pb in entity_pbs:
entities.append(helpers.entity_from_protobuf(entity_pb))
return entities
