def modify_write(self, write_pb, no_create_msg=None):
"""Modify a ``Write`` protobuf based on the state of this write option.
If:
* ``create_if_missing=False``, adds a precondition that requires
existence
* ``create_if_missing=True``, does not add any precondition
* ``no_create_msg`` is passed, raises an exception. For example, in a
:meth:`~.DocumentReference.delete`, no "create" can occur, so it
wouldn't make sense to "create if missing".
Args:
write_pb (google.cloud.firestore_v1beta1.types.Write): A
``Write`` protobuf instance to be modified with a precondition
determined by the state of this option.
no_create_msg (Optional[str]): A message to use to indicate that
a create operation is not allowed.
Raises:
ValueError: If ``no_create_msg`` is passed.
"""
if no_create_msg is not None:
raise ValueError(no_create_msg)
elif not self._create_if_missing:
current_doc = types.Precondition(exists=True)
write_pb.current_document.CopyFrom(current_doc)
def modify_write(self, write_pb, **unused_kwargs):
"""Modify a ``Write`` protobuf based on the state of this write option.
The ``last_update_time`` is added to ``write_pb`` as an "update time"
precondition. When set, the target document must exist and have been
last updated at that time.
Args:
write_pb (google.cloud.firestore_v1beta1.types.Write): A
``Write`` protobuf instance to be modified with a precondition
determined by the state of this option.
unused_kwargs (Dict[str, Any]): Keyword arguments accepted by
other subclasses that are unused here.
"""
current_doc = types.Precondition(update_time=self._last_update_time)
write_pb.current_document.CopyFrom(current_doc)
def modify_write(self, write_pb, **unused_kwargs):
"""Modify a ``Write`` protobuf based on the state of this write option.
If:
* ``exists=True``, adds a precondition that requires existence
* ``exists=False``, adds a precondition that requires non-existence
Args:
write_pb (google.cloud.firestore_v1beta1.types.Write): A
``Write`` protobuf instance to be modified with a precondition
determined by the state of this option.
unused_kwargs (Dict[str, Any]): Keyword arguments accepted by
other subclasses that are unused here.
"""
current_doc = types.Precondition(exists=self._exists)
write_pb.current_document.CopyFrom(current_doc)
