Documents

Classes for representing documents for the Google Cloud Firestore API.

class google.cloud.firestore_v1.document.DocumentReference(*path, **kwargs)

Bases: object

A reference to a document in a Firestore database.

The document may already exist or can be created by this class.

  • Parameters

    • path (Tuple[str, **...]) – The components in the document 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 (as well as the base document).

    • kwargs (dict) – The keyword arguments for the constructor. The only supported keyword is client and it must be a Client. It represents the client that created this document 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.

_copy_()

Shallow copy the instance.

We leave the client “as-is” but tuple-unpack the path.

  • Returns

    A copy of the current document.

  • Return type

    DocumentReference

_deepcopy_(unused_memo)

Deep copy the instance.

This isn’t a true deep copy, wee leave the client “as-is” but tuple-unpack the path.

  • Returns

    A copy of the current document.

  • Return type

    DocumentReference

_eq_(other)

Equality check against another instance.

  • Parameters

    other (Any) – A value to compare against.

  • Returns

    Indicating if the values are equal.

  • Return type

    Union[bool, NotImplementedType]

_ne_(other)

Inequality check against another instance.

  • Parameters

    other (Any) – A value to compare against.

  • Returns

    Indicating if the values are not equal.

  • Return type

    Union[bool, NotImplementedType]

collection(collection_id)

Create a sub-collection underneath the current document.

  • Parameters

    collection_id (str) – The sub-collection identifier (sometimes referred to as the “kind”).

  • Returns

    The child collection.

  • Return type

    CollectionReference

collections(page_size=None)

List subcollections of the current document.

  • Parameters

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

    • 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 subcollections of the current document. If the document does not exist at the time of snapshot, the iterator will be empty

  • Return type

    Sequence[CollectionReference]

create(document_data)

Create the current document in the Firestore database.

  • Parameters

    document_data (dict) – Property names and values to use for creating a document.

  • Returns

    The write result corresponding to the committed document. A write result contains an update_time field.

  • Return type

    WriteResult

  • Raises

    Conflict – If the document already exists.

delete(option=None)

Delete the current document in the Firestore database.

  • Parameters

    option (Optional[WriteOption]) – A write option to make assertions / preconditions on the server state of the document before applying changes.

  • Returns

    The time that the delete request was received by the server. If the document did not exist when the delete was sent (i.e. nothing was deleted), this method will still succeed and will still return the time that the request was received by the server.

  • Return type

    google.protobuf.timestamp_pb2.Timestamp

get(field_paths=None, transaction=None)

Retrieve a snapshot of the current document.

See field_path() for more information on field paths.

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

    • field_paths (Optional[Iterable[str, **...]]) – An iterable of field paths (.-delimited list of field names) to use as a projection of document fields in the returned results. If no value is provided, all fields will be returned.

    • transaction (Optional[Transaction]) – An existing transaction that this reference will be retrieved in.

  • Returns

    A snapshot of the current document. If the document does not exist at the time of the snapshot is taken, the snapshot’s reference, data, update_time, and create_time attributes will all be None and its exists attribute will be False.

  • Return type

    DocumentSnapshot

property id()

The document identifier (within its collection).

  • Returns

    The last component of the path.

  • Return type

    str

on_snapshot(callback)

Watch this document.

This starts a watch on this document using a background thread. The provided callback is run on the snapshot.

  • Parameters

    callback (Callable[[DocumentSnapshot], 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(document_snapshot, changes, read_time):
    doc = document_snapshot
    print(u'{} => {}'.format(doc.id, doc.to_dict()))

doc_ref = db.collection(u'users').document(
    u'alovelace' + unique_resource_id())

# Watch this document
doc_watch = doc_ref.on_snapshot(on_snapshot)

# Terminate this watch
doc_watch.unsubscribe()

property parent()

Collection that owns the current document.

property path()

Database-relative for this document.

  • Returns

    The document’s relative path.

  • Return type

    str

set(document_data, merge=False)

Replace the current document in the Firestore database.

A write option can be specified to indicate preconditions of the “set” operation. If no option is specified and this document doesn’t exist yet, this method will create it.

Overwrites all content for the document with the fields in document_data. This method performs almost the same functionality as create(). The only difference is that this method doesn’t make any requirements on the existence of the document (unless option is used), whereas as create() will fail if the document already exists.

  • Parameters

    • document_data (dict) – Property names and values to use for replacing a document.

    • merge (Optional[bool] or **Optional[List]) – If True, apply merging instead of overwriting the state of the document.

  • Returns

    The write result corresponding to the committed document. A write result contains an update_time field.

  • Return type

    WriteResult

update(field_updates, option=None)

Update an existing document in the Firestore database.

By default, this method verifies that the document exists on the server before making updates. A write option can be specified to override these preconditions.

Each key in field_updates can either be a field name or a field path (For more information on field paths, see field_path().) To illustrate this, consider a document with

>>> snapshot = document.get()
>>> snapshot.to_dict()
{
    'foo': {
        'bar': 'baz',
    },
    'other': True,
}

stored on the server. If the field name is used in the update:

>>> field_updates = {
...     'foo': {
...         'quux': 800,
...     },
... }
>>> document.update(field_updates)

then all of foo will be overwritten on the server and the new value will be

>>> snapshot = document.get()
>>> snapshot.to_dict()
{
    'foo': {
        'quux': 800,
    },
    'other': True,
}

On the other hand, if a .-delimited field path is used in the update:

>>> field_updates = {
...     'foo.quux': 800,
... }
>>> document.update(field_updates)

then only foo.quux will be updated on the server and the field foo.bar will remain intact:

>>> snapshot = document.get()
>>> snapshot.to_dict()
{
    'foo': {
        'bar': 'baz',
        'quux': 800,
    },
    'other': True,
}

WARNING: A field path can only be used as a top-level key in field_updates.

To delete / remove a field from an existing document, use the DELETE_FIELD sentinel. So with the example above, sending

>>> field_updates = {
...     'other': firestore.DELETE_FIELD,
... }
>>> document.update(field_updates)

would update the value on the server to:

>>> snapshot = document.get()
>>> snapshot.to_dict()
{
    'foo': {
        'bar': 'baz',
    },
}

To set a field to the current time on the server when the update is received, use the SERVER_TIMESTAMP sentinel. Sending

>>> field_updates = {
...     'foo.now': firestore.SERVER_TIMESTAMP,
... }
>>> document.update(field_updates)

would update the value on the server to:

>>> snapshot = document.get()
>>> snapshot.to_dict()
{
    'foo': {
        'bar': 'baz',
        'now': datetime.datetime(2012, ...),
    },
    'other': True,
}

  • Parameters

    • field_updates (dict) – Field names or paths to update and values to update with.

    • option (Optional[WriteOption]) – A write option to make assertions / preconditions on the server state of the document before applying changes.

  • Returns

    The write result corresponding to the updated document. A write result contains an update_time field.

  • Return type

    WriteResult

  • Raises

    NotFound – If the document does not exist.

class google.cloud.firestore_v1.document.DocumentSnapshot(reference, data, exists, read_time, create_time, update_time)

Bases: object

A snapshot of document data in a Firestore database.

This represents data retrieved at a specific time and may not contain all fields stored for the document (i.e. a hand-picked selection of fields may have been retrieved).

Instances of this class are not intended to be constructed by hand, rather they’ll be returned as responses to various methods, such as get().

  • Parameters

    • reference (DocumentReference) – A document reference corresponding to the document that contains the data in this snapshot.

    • data (Dict[str, *[Any](types.md#google.cloud.firestore_v1.types.Any)]*) – The data retrieved in the snapshot.

    • exists (bool) – Indicates if the document existed at the time the snapshot was retrieved.

    • read_time (google.protobuf.timestamp_pb2.Timestamp) – The time that this snapshot was read from the server.

    • create_time (google.protobuf.timestamp_pb2.Timestamp) – The time that this document was created.

    • update_time (google.protobuf.timestamp_pb2.Timestamp) – The time that this document was last updated.

property exists()

Existence flag.

Indicates if the document existed at the time this snapshot was retrieved.

  • Returns

    The existence flag.

  • Return type

    bool

get(field_path)

Get a value from the snapshot data.

If the data is nested, for example:

>>> snapshot.to_dict()
{
    'top1': {
        'middle2': {
            'bottom3': 20,
            'bottom4': 22,
        },
        'middle5': True,
    },
    'top6': b'  foo',
}

a field path can be used to access the nested data. For example:

>>> snapshot.get('top1')
{
    'middle2': {
        'bottom3': 20,
        'bottom4': 22,
    },
    'middle5': True,
}
>>> snapshot.get('top1.middle2')
{
    'bottom3': 20,
    'bottom4': 22,
}
>>> snapshot.get('top1.middle2.bottom3')
20

See field_path() for more information on field paths.

A copy is returned since the data may contain mutable values, but the data stored in the snapshot must remain immutable.

  • Parameters

    field_path (str) – A field path (.-delimited list of field names).

  • Returns

    (A copy of) the value stored for the field_path or None if snapshot document does not exist.

  • Return type

    Any or None

  • Raises

    KeyError – If the field_path does not match nested data in the snapshot.

property id()

The document identifier (within its collection).

  • Returns

    The last component of the path of the document.

  • Return type

    str

property reference()

Document reference corresponding to document that owns this data.

  • Returns

    A document reference corresponding to this document.

  • Return type

    DocumentReference

to_dict()

Retrieve the data contained in this snapshot.

A copy is returned since the data may contain mutable values, but the data stored in the snapshot must remain immutable.

  • Returns

    The data in the snapshot. Returns None if reference does not exist.

  • Return type

    Dict[str, Any] or None