Extend entity - add new attribute

Configuration
1

I suspect that this might be a question for Developers but is it possible to extend an entity by adding an attribute? Specifically I have a few blinds e.g.

entity:
    cover.blind_bedroom_2
attributes:
    current_position: 100
    device_class: shutter
    friendly_name: Blind Bedroom 2
    supported_features: 15

and I want to add an attribute “velocity:” which would contain a value e.g. fast or slow, which would be used in deciding how quickly the blind opened or closed?

2

you can add any attribute using customize, but those would be fixed.

homeassisant:
  customize:
    cover.blind_bedroom_2:
      velocity: fast

do you want them to be dynamic? that would not be possiile (without custom components)

3

Hi Marius. Thanks.
I think that might work as I always want the bedroom blinds to go slowly and the hall ones to go fast.

homeassisant:
  customize:
    cover.blind_bedroom_2:
      velocity: slow
    cover.blind_hall:
      velocity: fast

The next step of passing those values to a python programme could be more fun !