nest_hub

Home Assistant pyscript for using Nest Hub as a dashboard

Nest Hub is not designed to be a dashboard, but it is quite a good fit. The only problem with it is that there is no easy way to run a custom app on it (i.e. you cannot click a button on the screen to launch the dashboard). To address this issue, we can use a script to decide when to cast the dashboard to the device. The script watches the state of one or more Nest Hub devices, and cast the dashboard to them based under the configured conditions. To use this script, you need to pyscript installed in your Home Assistant server. Note that Nest Hub devices may go back to the main screen after 10 minutes idle time. This can be fixed by installing ha-catt-fix. The script is only tested on Nest Hub 2nd-gen. DashCast is required for this script.

The script works the best when the device is a dedicated dashboard (i.e. you don't want to use it for anything else). In this case, it will try to cast the dashboard whenever the device is not showing the dashboard. This can be relaxed by tuning the various duration in the config.

Install

Install pyscript and DashCast and ha-catt-fix (optional) from HACS.

Create a nest_hub folder under /config/pyscript/apps/, and put __init__.py in it. Then, in pyscript's configuration, add the following section:

apps:
  nest_hub:
    dashboard_url: <your dashboard url> # you can also use !secret dashboard_url
    off_duratoin: 0
    entities:
      - <entity ID of a Nest Hub device>
      - ...

Configuration

Field	Description	Type	Default	Required
dashboard_url	The URL to cast.	string		Yes
entities	A list of Nest Hub entities. See below.	list		Yes
enable_switch	If set, the entity ID specified in this field (usually an input_boolean) will be used to control whether the dashboard should be casted.	string		No
off_duration	If >= 0, the script will cast the dashboard to the device when its state is off for the specified number of seconds. Can be set to a negative number to disable the feature. If you set this field to 0, the script will aggressively cast the dashboard to the device. You may not be able to use the device for other purposes.	int	10	No
idle_duration	If >= 0, the script will cast the dashboard to the device when its state is idle for the specified number of seconds. Can be set to a negative number to disable the feature.	int	180	No
paused_duration	If >= 0, the script will cast the dashboard to the device when its state is paused for the specified number of seconds. Can be set to a negative number to disable the feature.	int	180	No
dark_theme	If set, the frontend theme will be set to this value when the sun goes down. This setting applies to the whole system.	string		No
light_theme	If set, the frontend theme will be set to this value when the sun goes up. This setting applies to the whole system.	string		No
boot_delay	The number of seconds to wait before casting if the device went offline and came back online.	int	20	No
mute_before_recast	If true, the script will mute the device before casting.	bool	true	No
restore_volume_level	If true, the script will restore the volume after casting. This only works if mute_before_recast is true.	bool	true	No
recast_on_start	If true, the script will cast the dashboard when Home Assistant starts, or when the script is reloaded.	bool	true	No

Specifying Entities

The entries in the entities field can be either a simple string specifying the entity ID of a Nest Hub device, or a dict specifying per-device configuration. For the second case, all of the configuration fields above can be specified, which will override the global settings. The field entity_id needs to be specified in the per-device configuration dict.

Example

apps:
  nest_hub:
    dashboard_url: !secret dashboard_url
    off_duration: 0
    mute_before_recast: true
    restore_volume_level: false
    entities:
      - entity_id: media_player.nest_hub_study
        off_duration: 10
        restore_volume_level: true
      - media_player.nest_hub_living_room