Days until template sensor

[ashscott (Ash)]

I have a date that is a string in the format 10/06/2023.

I need to have a sensor that shows the number of days to go until that date.

Where do I start with this?

I’m thinking that the string first needs to be converted into a date and then converted into number of days.

I’ll then need to compare that with today’s date.

I’d rather not have a finished solution, just some pointers as to where to start.

[Dujith (Charles Evers)]

Template Guide: Days away from calendar event

I keep seeing questions about calculating days away from a calendar date. Here’s a “simple” template that will solve that problem for anyone. {% set midnight = today_at() %} {% set event = state_attr('calendar.xxx', 'start_time') | as_datetime | as_local %} {% set delta = event - midnight %} {% if delta.days == 0 %} Today {% elif delta.days == 1 %} Tomorrow {% elif delta.days == 2 %} Day After Tomorrow {% else %} In {{ delta.days }} Days {% endif %} Explanation This first line grabs …

This will explain the how. So you can also set a date helper for this or another entity.

[123 (Taras)]

Copy-paste the following template into the Template Editor and confirm it reports the desired result.

{{ (strptime('10/06/2023', '%m/%d/%Y', today_at()) | as_local - today_at()).days }}

Replace '10/06/2023' with states('sensor.your_sensor') or whatever is needed to get the date string.

[ashscott (Ash)]

Thank you! That works brilliantly.

I’m using {{ states('sensor.my_date')[-11:] }} to get the 10/06/23 and it returns the string correctly.

Substituting it into your template thus…

{{ (strptime(states('sensor.my_date')[-11:], '%m/%d/%Y', today_at()) | as_local - today_at()).days }}

… it just returns 0 as the result.

Am I expecting too much of it?
Does it need to be done in two steps?

The original string takes the form "196 hrs or 10/06/2024"

This is what I’m pasting into the Template Editor:

{{ states('sensor.my_date')[:3] }}

{{ states('sensor.my_date')[-11:] }}

{{ (strptime(states('sensor.my_date')[-11:], '%m/%d/%Y', today_at()) | as_local - today_at()).days }}

{{ (strptime('10/06/2023', '%m/%d/%Y', today_at()) | as_local - today_at()).days }}

And that returns this:

196

10/06/2024 

0

314

Which highlights another issue.

When the 196 hrs changes to 99 hrs the {{ states('sensor.my_date')[:3] }} it will return "99 ", as there are only two digits. Same problem when it reaches 9.

Is there a way to extract the number up to the first “space”?

[123 (Taras)]

Change [-11:] to [-10:] because the date string is ten characters long.

[-11:] will include a leading space which doesn’t match strptime’s pattern. As a consequence, strptime reports its default value which is today_at().

[ashscott (Ash)]

I looked at that, but changing it to -10 loses the 1, resulting in a date of 0/06/2024.

In principle though, should it work? If so then an erroneous character may well be the problem, as you suggest.

[123 (Taras)]

That behavior implies there’s a trailing space character in the original string.

Try this:

states('sensor.my_date')[-11:] | trim

Revised example:

{{ (strptime(states('sensor.my_date')[-11:] | trim, '%m/%d/%Y', today_at()) | as_local - today_at()).days }}

[ashscott (Ash)]

Excellent. Thank you.

So, ‘trim’ removes just trailing spaces?

Is there something similar to deal with the varying lengths, as per my 196 to 99 hours problem above?
I don’t think there are leading spaces there but just extracting up to the first space would solve the problem.

[123 (Taras)]

trim removes leading and trailing white space.

@ashscott

Is there a way to extract the number up to the first “space”?

If the string always contains hrs or you can use it as a delimiter in split(). The result will be a list containing two items, 99 and 10/06/2024 , that can be referenced by list index.

Try this in the Template Editor:

{% set x =  states('sensor.my_date').split(' hrs or ') %}
{{ x[0] }}
{{ x[1] | trim }}

[ashscott (Ash)]

Thank you.

That works.

In English, for my understanding, it’s taking the string and removing everything on either side of what is in the split().

This then leaves a list, x, with each list item being referenced by [y].

You have taught me so much!

Thank you and have a great weekend.

[123 (Taras)]

You’re welcome!

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[JabeBRD (Jami Toivonen)]

I cant get this to works, i want to calculate how many days my HA-server has been running, using system monitor sensor value.
I have set up helper with this.

{{ (strptime(states('sensor.system_monitor_viimeinen_kaynnistys'), '%m/%d/%Y', today_at()) | as_local - today_at()).days }}

It returns 0, tried trimming but didnt work, when I replace states(‘sensor…’) with date like 10/05/2024, it gives me days in negative, i would like to get days in positive, but didnt figure it out.

[Troon]

What is the state of sensor.system_monitor_viimeinen_kaynnistys?

@JabeBRD

it gives me days in negative,

That’s because you are subtracting a later time from an earlier one.

[JabeBRD (Jami Toivonen)]

I tried to change that order, but i didnt get any results, it allways reported Unknown.
That sensor gives May 22, 2024 at 20:33
Found other way, it worked. But i have read to not use as_timestamp(now() and it should be replaced by Time&Date, but didnt get that to work either, is my date formating wrong, tried time_date and date_time?

{{ (((as_timestamp(now()) - as_timestamp(states('sensor.system_monitor_viimeinen_kaynnistys')))) | int /60/1440) | round(0) }}

[123 (Taras)]

@JabeBRD

i have read to not use as_timestamp(now() and it should be replaced by Time&Date

Do you recall where you read that?

Because it sounds like outdated advice.

[petro]

I believe they are miss understanding the advice. The advice is most likely referencing datetime objects over the use of as_timestamp, which is suggested because datetime objects handle timezones better than as_timestamp.

{{ (now() - states('sensor.system_monitor_viimeinen_kaynnistys') | as_datetime).days }}

[Troon]

With the format in that sensor, you need something like:

strptime(states('sensor.system_monitor_viimeinen_kaynnistys'), "%B %d, %Y at %H:%M")

to get a datetime object out of it, then you’d need to assign a timezone.

Both of these return something, but don’t take timezones into consideration:

{{ time_since(strptime("May 22, 2024 at 20:33", "%B %d, %Y at %H:%M")) }}
{{ now()|as_timestamp - strptime("May 22, 2024 at 20:33", "%B %d, %Y at %H:%M")|as_timestamp }}

[petro]

He’s claiming that as_timestamp is working unless I miss read something. Both as_timestamp and as_datetime use the same underlying code to determine the date from an iso (or some non-iso) formats.

If his format is truly May 22, 2024 at 20:33, then he will need to use strptime like you say.

{{ now() - strptime("May 22, 2024 at 20:33", "%B %d, %Y at %H:%M")|as_local}}

in his case

{{ (now() - strptime(states('sensor.system_monitor_viimeinen_kaynnistys'), "%B %d, %Y at %H:%M")|as_local).days }}

[123 (Taras)]

I had the impression that the advice was about using Time&Date sensors instead of now() which would have been applicable a long, long time ago when now() didn’t serve to periodically update a template.

Anyways, we’ve yet to hear from JabeBRD.

[petro]

I completely forgot about those, been so long