Issue with Firestore Trigger on_document_created_with_auth_context

[antoniobocale]

I am trying to use the Firestore trigger on_document_created_with_auth_context to get user info along with the document. However, the event data I receive is of type DocumentEventData instead of DocumentSnapshot. As a result, I cannot access the document fields using the get method. Instead, I receive the following error:

AttributeError: Unknown field for DocumentEventData: get

Steps to Reproduce

1. Set up a Firestore trigger using on_document_created_with_auth_context.
2. Attempt to access document fields using the get method on the event data.
3. Observe the error mentioned above.

from firebase_functions.firestore_fn import AuthEvent, DocumentSnapshot, on_document_created_with_auth_context

@on_document_created_with_auth_context(document="*")
def document_created(event: AuthEvent[DocumentSnapshot]):
    event.data.get("field")

Expected Behavior

The event data should be of type DocumentSnapshot, allowing access to document fields using the get method, similar to the behavior of the on_document_created trigger.

Actual Behavior

The event data is of type DocumentEventData, which does not support the get method, resulting in an AttributeError.

Additional Information

When using the on_document_created trigger, the event data is of type DocumentSnapshot, and I can access document fields without any issues. However, with on_document_created_with_auth_context, the event data type is DocumentEventData, leading to the error.

Is this the intended behavior, or should the event data be of type DocumentSnapshot similar to on_document_created? If not, how should this be resolved?

[andreas-thomik]

I ran into a similar issue trying to access .before and .after on change triggers.

I think the root cause is in the _firestore_endpoint_handler function, specifically the following statements:

    if event_type == _event_type_deleted:
        firestore_event_data = _typing.cast(_firestore.DocumentEventData,
                                            old_value_snapshot)
    if event_type == _event_type_created:
        firestore_event_data = _typing.cast(_firestore.DocumentEventData,
                                            value_snapshot)
    if event_type in (_event_type_written, _event_type_updated):
        firestore_event_data = _typing.cast(
            _firestore.DocumentEventData,
            Change(
                before=old_value_snapshot,
                after=value_snapshot,
            ))

They ignore the fact that _event_type can also be any of the above with the _with_auth_context suffix.

As a workaround for local development, adding the missing event types to the if event_type ... statements works but obviously does not work when actually trying to deploy a function. That would require a new release.

[exaby73]

Thanks for bringing this to my attention. Investigating it now