Support for tailable cursors

[vd2org]

Support for tailable cursors in engine.find call:

https://motor.readthedocs.io/en/stable/examples/tailable-cursors.html

[art049]

Hi, can you describe the behavior you would like to have with the current AIOCursor ?

[vd2org]

Hi! Same as simple find, but I want to wait until new documents come in.
This will be useful, for example, for implementing event notifications over websocket.

Something like that:

async for rec of engine.find(EventsModel, EventsModel.timestamp >= datetime.utcnow().timestamp(), tailable=True):
   await websocket.send(dict(rec))