Vehicle-Anti-Theft-Face-Rec.../venv/Lib/site-packages/google/cloud/firestore_v1beta1/collection.py

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# Copyright 2017 Google LLC All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Classes for representing collections for the Google Cloud Firestore API."""
import random
import warnings
import six
from google.cloud.firestore_v1beta1 import _helpers
from google.cloud.firestore_v1beta1 import query as query_mod
from google.cloud.firestore_v1beta1.proto import document_pb2
from google.cloud.firestore_v1beta1.watch import Watch
from google.cloud.firestore_v1beta1 import document
_AUTO_ID_CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
class CollectionReference(object):
"""A reference to a collection in a Firestore database.
The collection may already exist or this class can facilitate creation
of documents within the collection.
Args:
path (Tuple[str, ...]): The components in the collection path.
This is a series of strings representing each collection and
sub-collection ID, as well as the document IDs for any documents
that contain a sub-collection.
kwargs (dict): The keyword arguments for the constructor. The only
supported keyword is ``client`` and it must be a
:class:`~google.cloud.firestore_v1beta1.client.Client` if
provided. It represents the client that created this collection
reference.
Raises:
ValueError: if
* the ``path`` is empty
* there are an even number of elements
* a collection ID in ``path`` is not a string
* a document ID in ``path`` is not a string
TypeError: If a keyword other than ``client`` is used.
"""
def __init__(self, *path, **kwargs):
_helpers.verify_path(path, is_collection=True)
self._path = path
self._client = kwargs.pop("client", None)
if kwargs:
raise TypeError(
"Received unexpected arguments", kwargs, "Only `client` is supported"
)
def __eq__(self, other):
if not isinstance(other, self.__class__):
return NotImplemented
return self._path == other._path and self._client == other._client
@property
def id(self):
"""The collection identifier.
Returns:
str: The last component of the path.
"""
return self._path[-1]
@property
def parent(self):
"""Document that owns the current collection.
Returns:
Optional[~.firestore_v1beta1.document.DocumentReference]: The
parent document, if the current collection is not a
top-level collection.
"""
if len(self._path) == 1:
return None
else:
parent_path = self._path[:-1]
return self._client.document(*parent_path)
def document(self, document_id=None):
"""Create a sub-document underneath the current collection.
Args:
document_id (Optional[str]): The document identifier
within the current collection. If not provided, will default
to a random 20 character string composed of digits,
uppercase and lowercase and letters.
Returns:
~.firestore_v1beta1.document.DocumentReference: The child
document.
"""
if document_id is None:
document_id = _auto_id()
child_path = self._path + (document_id,)
return self._client.document(*child_path)
def _parent_info(self):
"""Get fully-qualified parent path and prefix for this collection.
Returns:
Tuple[str, str]: Pair of
* the fully-qualified (with database and project) path to the
parent of this collection (will either be the database path
or a document path).
* the prefix to a document in this collection.
"""
parent_doc = self.parent
if parent_doc is None:
parent_path = _helpers.DOCUMENT_PATH_DELIMITER.join(
(self._client._database_string, "documents")
)
else:
parent_path = parent_doc._document_path
expected_prefix = _helpers.DOCUMENT_PATH_DELIMITER.join((parent_path, self.id))
return parent_path, expected_prefix
def add(self, document_data, document_id=None):
"""Create a document in the Firestore database with the provided data.
Args:
document_data (dict): Property names and values to use for
creating the document.
document_id (Optional[str]): The document identifier within the
current collection. If not provided, an ID will be
automatically assigned by the server (the assigned ID will be
a random 20 character string composed of digits,
uppercase and lowercase letters).
Returns:
Tuple[google.protobuf.timestamp_pb2.Timestamp, \
~.firestore_v1beta1.document.DocumentReference]: Pair of
* The ``update_time`` when the document was created (or
overwritten).
* A document reference for the created document.
Raises:
~google.cloud.exceptions.Conflict: If ``document_id`` is provided
and the document already exists.
"""
if document_id is None:
parent_path, expected_prefix = self._parent_info()
document_pb = document_pb2.Document()
created_document_pb = self._client._firestore_api.create_document(
parent_path,
collection_id=self.id,
document_id=None,
document=document_pb,
mask=None,
metadata=self._client._rpc_metadata,
)
new_document_id = _helpers.get_doc_id(created_document_pb, expected_prefix)
document_ref = self.document(new_document_id)
set_result = document_ref.set(document_data)
return set_result.update_time, document_ref
else:
document_ref = self.document(document_id)
write_result = document_ref.create(document_data)
return write_result.update_time, document_ref
def list_documents(self, page_size=None):
"""List all subdocuments of the current collection.
Args:
page_size (Optional[int]]): The maximum number of documents
in each page of results from this request. Non-positive values
are ignored. Defaults to a sensible value set by the API.
Returns:
Sequence[~.firestore_v1beta1.collection.DocumentReference]:
iterator of subdocuments of the current collection. If the
collection does not exist at the time of `snapshot`, the
iterator will be empty
"""
parent, _ = self._parent_info()
iterator = self._client._firestore_api.list_documents(
parent,
self.id,
page_size=page_size,
show_missing=True,
metadata=self._client._rpc_metadata,
)
iterator.collection = self
iterator.item_to_value = _item_to_document_ref
return iterator
def select(self, field_paths):
"""Create a "select" query with this collection as parent.
See
:meth:`~google.cloud.firestore_v1beta1.query.Query.select` for
more information on this method.
Args:
field_paths (Iterable[str, ...]): An iterable of field paths
(``.``-delimited list of field names) to use as a projection
of document fields in the query results.
Returns:
~.firestore_v1beta1.query.Query: A "projected" query.
"""
query = query_mod.Query(self)
return query.select(field_paths)
def where(self, field_path, op_string, value):
"""Create a "where" query with this collection as parent.
See
:meth:`~google.cloud.firestore_v1beta1.query.Query.where` for
more information on this method.
Args:
field_path (str): A field path (``.``-delimited list of
field names) for the field to filter on.
op_string (str): A comparison operation in the form of a string.
Acceptable values are ``<``, ``<=``, ``==``, ``>=``
and ``>``.
value (Any): The value to compare the field against in the filter.
If ``value`` is :data:`None` or a NaN, then ``==`` is the only
allowed operation.
Returns:
~.firestore_v1beta1.query.Query: A filtered query.
"""
query = query_mod.Query(self)
return query.where(field_path, op_string, value)
def order_by(self, field_path, **kwargs):
"""Create an "order by" query with this collection as parent.
See
:meth:`~google.cloud.firestore_v1beta1.query.Query.order_by` for
more information on this method.
Args:
field_path (str): A field path (``.``-delimited list of
field names) on which to order the query results.
kwargs (Dict[str, Any]): The keyword arguments to pass along
to the query. The only supported keyword is ``direction``, see
:meth:`~google.cloud.firestore_v1beta1.query.Query.order_by`
for more information.
Returns:
~.firestore_v1beta1.query.Query: An "order by" query.
"""
query = query_mod.Query(self)
return query.order_by(field_path, **kwargs)
def limit(self, count):
"""Create a limited query with this collection as parent.
See
:meth:`~google.cloud.firestore_v1beta1.query.Query.limit` for
more information on this method.
Args:
count (int): Maximum number of documents to return that match
the query.
Returns:
~.firestore_v1beta1.query.Query: A limited query.
"""
query = query_mod.Query(self)
return query.limit(count)
def offset(self, num_to_skip):
"""Skip to an offset in a query with this collection as parent.
See
:meth:`~google.cloud.firestore_v1beta1.query.Query.offset` for
more information on this method.
Args:
num_to_skip (int): The number of results to skip at the beginning
of query results. (Must be non-negative.)
Returns:
~.firestore_v1beta1.query.Query: An offset query.
"""
query = query_mod.Query(self)
return query.offset(num_to_skip)
def start_at(self, document_fields):
"""Start query at a cursor with this collection as parent.
See
:meth:`~google.cloud.firestore_v1beta1.query.Query.start_at` for
more information on this method.
Args:
document_fields (Union[~.firestore_v1beta1.\
document.DocumentSnapshot, dict, list, tuple]): a document
snapshot or a dictionary/list/tuple of fields representing a
query results cursor. A cursor is a collection of values that
represent a position in a query result set.
Returns:
~.firestore_v1beta1.query.Query: A query with cursor.
"""
query = query_mod.Query(self)
return query.start_at(document_fields)
def start_after(self, document_fields):
"""Start query after a cursor with this collection as parent.
See
:meth:`~google.cloud.firestore_v1beta1.query.Query.start_after` for
more information on this method.
Args:
document_fields (Union[~.firestore_v1beta1.\
document.DocumentSnapshot, dict, list, tuple]): a document
snapshot or a dictionary/list/tuple of fields representing a
query results cursor. A cursor is a collection of values that
represent a position in a query result set.
Returns:
~.firestore_v1beta1.query.Query: A query with cursor.
"""
query = query_mod.Query(self)
return query.start_after(document_fields)
def end_before(self, document_fields):
"""End query before a cursor with this collection as parent.
See
:meth:`~google.cloud.firestore_v1beta1.query.Query.end_before` for
more information on this method.
Args:
document_fields (Union[~.firestore_v1beta1.\
document.DocumentSnapshot, dict, list, tuple]): a document
snapshot or a dictionary/list/tuple of fields representing a
query results cursor. A cursor is a collection of values that
represent a position in a query result set.
Returns:
~.firestore_v1beta1.query.Query: A query with cursor.
"""
query = query_mod.Query(self)
return query.end_before(document_fields)
def end_at(self, document_fields):
"""End query at a cursor with this collection as parent.
See
:meth:`~google.cloud.firestore_v1beta1.query.Query.end_at` for
more information on this method.
Args:
document_fields (Union[~.firestore_v1beta1.\
document.DocumentSnapshot, dict, list, tuple]): a document
snapshot or a dictionary/list/tuple of fields representing a
query results cursor. A cursor is a collection of values that
represent a position in a query result set.
Returns:
~.firestore_v1beta1.query.Query: A query with cursor.
"""
query = query_mod.Query(self)
return query.end_at(document_fields)
def get(self, transaction=None):
"""Deprecated alias for :meth:`stream`."""
warnings.warn(
"'Collection.get' is deprecated: please use 'Collection.stream' instead.",
DeprecationWarning,
stacklevel=2,
)
return self.stream(transaction=transaction)
def stream(self, transaction=None):
"""Read the documents in this collection.
This sends a ``RunQuery`` RPC and then returns an iterator which
consumes each document returned in the stream of ``RunQueryResponse``
messages.
.. note::
The underlying stream of responses will time out after
the ``max_rpc_timeout_millis`` value set in the GAPIC
client configuration for the ``RunQuery`` API. Snapshots
not consumed from the iterator before that point will be lost.
If a ``transaction`` is used and it already has write operations
added, this method cannot be used (i.e. read-after-write is not
allowed).
Args:
transaction (Optional[~.firestore_v1beta1.transaction.\
Transaction]): An existing transaction that the query will
run in.
Yields:
~.firestore_v1beta1.document.DocumentSnapshot: The next
document that fulfills the query.
"""
query = query_mod.Query(self)
return query.stream(transaction=transaction)
def on_snapshot(self, callback):
"""Monitor the documents in this collection.
This starts a watch on this collection using a background thread. The
provided callback is run on the snapshot of the documents.
Args:
callback(~.firestore.collection.CollectionSnapshot): a callback
to run when a change occurs.
Example:
from google.cloud import firestore_v1beta1
db = firestore_v1beta1.Client()
collection_ref = db.collection(u'users')
def on_snapshot(collection_snapshot):
for doc in collection_snapshot.documents:
print(u'{} => {}'.format(doc.id, doc.to_dict()))
# Watch this collection
collection_watch = collection_ref.on_snapshot(on_snapshot)
# Terminate this watch
collection_watch.unsubscribe()
"""
return Watch.for_query(
query_mod.Query(self),
callback,
document.DocumentSnapshot,
document.DocumentReference,
)
def _auto_id():
"""Generate a "random" automatically generated ID.
Returns:
str: A 20 character string composed of digits, uppercase and
lowercase and letters.
"""
return "".join(random.choice(_AUTO_ID_CHARS) for _ in six.moves.xrange(20))
def _item_to_document_ref(iterator, item):
"""Convert Document resource to document ref.
Args:
iterator (google.api_core.page_iterator.GRPCIterator):
iterator response
item (dict): document resource
"""
document_id = item.name.split(_helpers.DOCUMENT_PATH_DELIMITER)[-1]
return iterator.collection.document(document_id)