Collections#

Classes for representing collections for the Google Cloud Firestore API.

class google.cloud.firestore_v1.collection.CollectionReference(*path, **kwargs)[source]#

Bases: 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.

Parameters
  • 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 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.

add(document_data, document_id=None)[source]#

Create a document in the Firestore database with the provided data.

Parameters
  • 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

Pair of

  • The update_time when the document was created/overwritten.

  • A document reference for the created document.

Return type

Tuple[google.protobuf.timestamp_pb2.Timestamp, DocumentReference]

Raises

Conflict – If document_id is provided and the document already exists.

document(document_id=None)[source]#

Create a sub-document underneath the current collection.

Parameters

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

The child document.

Return type

DocumentReference

end_at(document_fields)[source]#

End query at a cursor with this collection as parent.

See end_at() for more information on this method.

Parameters

document_fields (Union[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

A query with cursor.

Return type

Query

end_before(document_fields)[source]#

End query before a cursor with this collection as parent.

See end_before() for more information on this method.

Parameters

document_fields (Union[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

A query with cursor.

Return type

Query

get(transaction=None)[source]#

Deprecated alias for stream().

property id#

The collection identifier.

Returns

The last component of the path.

Return type

str

limit(count)[source]#

Create a limited query with this collection as parent.

See limit() for more information on this method.

Parameters

count (int) – Maximum number of documents to return that match the query.

Returns

A limited query.

Return type

Query

list_documents(page_size=None)[source]#

List all subdocuments of the current collection.

Parameters
  • page_size (Optional[int]]) – The maximum number of documents

  • each page of results from this request. Non-positive values (in) –

  • ignored. Defaults to a sensible value set by the API. (are) –

Returns

iterator of subdocuments of the current collection. If the collection does not exist at the time of snapshot, the iterator will be empty

Return type

Sequence[DocumentReference]

offset(num_to_skip)[source]#

Skip to an offset in a query with this collection as parent.

See offset() for more information on this method.

Parameters

num_to_skip (int) – The number of results to skip at the beginning of query results. (Must be non-negative.)

Returns

An offset query.

Return type

Query

on_snapshot(callback)[source]#

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.

Parameters

callback (Callable[[CollectionSnapshot], NoneType]) – a callback to run when a change occurs.

Example

from google.cloud import firestore_v1

db = firestore_v1.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()

order_by(field_path, **kwargs)[source]#

Create an “order by” query with this collection as parent.

See order_by() for more information on this method.

Parameters
  • 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 order_by() for more information.

Returns

An “order by” query.

Return type

Query

property parent#

Document that owns the current collection.

Returns

The parent document, if the current collection is not a top-level collection.

Return type

Optional[DocumentReference]

select(field_paths)[source]#

Create a “select” query with this collection as parent.

See select() for more information on this method.

Parameters

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

A “projected” query.

Return type

Query

start_after(document_fields)[source]#

Start query after a cursor with this collection as parent.

See start_after() for more information on this method.

Parameters

document_fields (Union[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

A query with cursor.

Return type

Query

start_at(document_fields)[source]#

Start query at a cursor with this collection as parent.

See start_at() for more information on this method.

Parameters

document_fields (Union[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

A query with cursor.

Return type

Query

stream(transaction=None)[source]#

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).

Parameters

transaction (Optional[                Transaction]) – An existing transaction that the query will run in.

Yields

DocumentSnapshot – The next document that fulfills the query.

where(field_path, op_string, value)[source]#

Create a “where” query with this collection as parent.

See where() for more information on this method.

Parameters
  • 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 None or a NaN, then == is the only allowed operation.

Returns

A filtered query.

Return type

Query