Building a reusable template

Configuration
1

In the spirit of DRY (Don’t repeat yourself), I’m looking to build a resusable sensor template. My suspicion is that this needs to be a custom component, but before I go down that route I want to ensure there isn’t another way.

I have the following repeated four times in my config, once for each member of the family. The only bit that changes is the proximity sensor (in this case proximity.ali_travel). Essentially, the sensor shows how far someone is from home, and changes the icon depending on at home, moving (away/towards home) or parked away from home.

So can this be packaged in such a way that it can be reused by just passing in the proximity sensor?

    ali_travel:
      friendly_name: Ali Travel
      value_template: >
        {% if states('proximity.ali_travel') == '0' -%}
          Home
        {%- else -%}
          {{ states('proximity.ali_travel') }} {{ state_attr('proximity.ali_travel', 'unit_of_measurement') }}
        {%- endif %}
      icon_template: >
        {% if states('proximity.ali_travel') == '0' -%}
        mdi:home-outline
        {%- elif state_attr('proximity.ali_travel', 'dir_of_travel') == 'stationary' -%}
        mdi:car-brake-parking
        {%- elif state_attr('proximity.ali_travel', 'dir_of_travel') == 'towards' -%}
          mdi:home-import-outline
        {%- elif state_attr('proximity.ali_travel', 'dir_of_travel') == 'away_from' -%}
        mdi:home-export-outline
        {%- else -%}
        mdi:car-off
        {%- endif %}
1 Like
2

A Template Sensor’s YAML configuration doesn’t allow you to pass anything to it.

3

I realise that, that was why I was seeing if this could be moved into it’s own template somehow. I’m thinking my only option is to build a custom component.

4

There’s no native facility to template YAML configurations for Template Sensors.

FWIW, there’s a custom facility for Dashboard YAML configurations. Perhaps you can use that for inspiration while creating your custom component.

1 Like
5

You can try to do the same with blueprints and helpers maybe,

The issue remain the same, you will have duplicated automations.

Another option might be the use of AppDeamon

6

Neither are for creating Template Sensors (the example in the first post is a Template Sensor).

Reference: Blueprints

7

Sure it would be updating a sensor with an automation and not templating.

But there’s actually no integrates way to avoid repetition.

With repetitive configuration file, when there’s no way to avoid repetition I tend to generate my config file with a script, therefore even if the code repeat itself I do not repeat myself and edits are way faster.

So you can use dedicated yalm file generated programmatically

8

The request isn’t for updating a sensor.

The request is for a method to easily create multiple instances of a single Template Sensor configuration, each with only minor differences. Effectively, a means of templating YAML. There’s no native facility for that purpose.

1 Like
9

I ran into the same issue. As of HA 2023.4, macros work nicely to reduce code duplication in templates, be it with some minor drawbacks at the moment.

3 Likes
10

If templates are not reusable, I don’t understand why they are named Templates.

11

Thanks for this! This was exactly what I was looking for. I was able to create a macro with functions that determine the amount of days remaining until my plants need water by passing the last watered date for each plant as a variable. Then I call the function in a template card on my dashboard.

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12

Came here sadly because I wanted an answer for this specific thing, too. I need to template a light because I’ve got a physical light that doesn’t respond well to specific parameters, so I need to swap it out for a virtual copy that eats the bad parameters. So I was hoping to be able to do something like this, but I cannot find any way there.

But, i do have an answer for some situations, such as the original poster here:

You could make a helper string or enum or number or whatever to contain status, and then create a blueprint automation that adjusts helper.X based on proxmity.Y .

At least for that case, that’d probably be a perfectly fine situation. Unfortunately, for mine, it doesn’t solve my problem, because I need to intercept the commands before they go out (i can automate fixing them after the fact if they come in from other sources this way, but i want to make sure that HA never sends out the bad commands)…

If templates are not reusable, I don’t understand why they are named Templates.

it’s because they can use template code inside them. not because they are reusable themselves, sadly.

13

Sounds like a Template Light… they can be configured in YAML or as a Helper in the UI.

14

yep, but copying a single template light many times for many devices is less than desireable … for one, it is fine, but i’ve got a whole case of these lights …

15

You can Blueprint template entities … Template - Home Assistant