I’ve been trying to learn some basics in Python and Jinja over the last few days and would now like to try to apply what I’ve learned to an example that combines a loop and an if then/else query with a state attribute.
Unfortunately, it’s not working, and I would appreciate it if one or two experienced template users could explain to me what I need to look out for or change so that I can learn and change it myself, rather than just telling me the solution…
That would be really great, thank you very much!
The idea was to list all sensors with the time of the last status update that have not had a status update for more than 24 hours:
{% for last_updated in ('sensor.name', 'last_updated') %}
{% if now() - last_updated >= timedelta (hours=24) %}
{{ sensor.name }}: {{ state_attr('sensor.name', 'last_updated') }}
{% endif %}
{% endfor %}
P.S. I would like to apologize in advance to all professionals for any mistakes I have made and thank you for your patience with me.
As one non-professional to another, welcome! Templates are one of Home Assistant’s most powerful features. Make sure to check out out templating guides listed in the Community Cookbook Index.
Where your template went wrong…
{% for last_updated in ('sensor.name', 'last_updated') %}
You created a loop that will run twice… once for the string ‘sensor.name’ and again for the string ‘last_updated’. While the loop is running, the variable last_updated will hold those strings as it’s value, each in it’s own turn. This can be seen in the following results from the Template Editor tool:
{% if now() - last_updated >= timedelta (hours=24) %}
Here you have created an impossible If statement criteria… you cannot subtract a string like ‘sensor.name’ or ‘last_updated’ from a datetime object like now(). This too can be demonstrated in the Template Editor:
3b. Unless you actually have an entity in your Home Assistant instance with the entity ID “sensor.name”, the second part will always render none. Also last_updated and last_changed are properties of the state object, not state attributes, so they are not accessible with the function state_attr().
Here are two ways to accomplish your goal. Note that in both cases, the variable sensor holds a sensor entity’s state object as its value during each turn of the loop, so properties like name and last_changed are accessible.
Using filters to select before looping (more efficient):
{%- for sensor in states.sensor | selectattr('last_changed', 'lt', now()-timedelta(hours=24))| list %}
{{ sensor.name }} : {{ sensor.last_changed }}
{%- endfor %}
or, using an If statement inside the loop:
{%- for sensor in states.sensor %}
{%- if sensor.last_changed < now() - timedelta(hours=24) %}
{{ sensor.name }} : {{ sensor.last_changed }}
{%- endif %}
{%- endfor %}
Is there an equivalent in Python/Jinja to PHP’s print_r(), dprint_r() or debug() to pretty print a sensor, together with all it’s attributes?
I’m really missing something like that in Python/Jinja.
