Ability to group entities into more than one Home Assistant/MQTT device

[dougiteixeira]

Describe the problem you have/What new integration you would like

We often use the same ESP device to connect sensors that are not always related but are physically close, taking better advantage of the ESP's GPIO.

In these cases, things can get pretty confusing on the Home Assistant, as the device will have a lot of unrelated entities.

With that in mind, I would like to suggest a resource so that it is possible to configure in ESPHome which device each entity will be linked to when exposed by the API or MQTT.

It would look something like the code below (omitting device_id in the component would keep the current behavior).

esphome:
  friendly_name: Device Default
[…]

devices:
  - id: device_1
    friendly_name: Device 1
  - id: device_2
    friendly_name: Device 2

[…]

sensor: 
  - platform: xxxxx
    device_id: device_1
    name: Sensor device 1

  - platform: xxxxx
    name: Sensor device default

switch:
  - platform: xxxxx
    device_id: device_2
    name: Switch device 2

These secondary devices would be linked to the main (default) device by Home Assistant's via_device property, making it easier to navigate between them in Home Assistant.

I don't have the knowledge to implement such features, so if anyone is willing to evaluate this possibility I would be very grateful!

This configuration would only have an effect on exposing the entities to the Home Assistant API or via MQTT (maybe including the webserver's dashbord?).

[nagyrobi]

Duplicate of #1335