How to use custom tests in Jinja template?

[123 (Taras)]

You have encountered the primary problem of using the entity’s name to store metadata: it’s messy to select entities by common metadata. Currently, there’s no easy way to select sub-strings from an entity’s name.

What I suggest is that you use custom attributes. I explained how to use them in this post:

Recommended ways to manage devices and entities names

I’m not an advocate of using an entity’s name to store metadata. In other words, I don’t recommend creating an entity name packed with its characteristics. sensor.manufacturer_model_identifier_color_size_location_bla_bla_etc When the time comes to select entities based on their characteristics, the resulting template can become quite messy. What I suggest is to add metadata as custom attributes to an entity. Simple add them to customize.yaml or via Configuration > Customizations. For example…

For example, if you create a custom attribute called ‘type’ and assign it a value like ‘schedule’ then you can easily select all entities having this attribute and value using this template:

{{ states.switch | selectattr('attributes.type', 'eq', 'schedule')
   | map(attribute='entity_id') | list }}