Add optional dsmr timestamp sensor

[dupondje]

Proposed change

Add an (optional) timestamp sensor which is set to the timestamp value of the dsmr telegram.
This can be useful sometimes as the time on the meter can sometimes have some offset. (12 seconds in my case now for example)

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Hey there @RobBie1221, @frenck, mind taking a look at this pull request as it has been labeled with an integration (dsmr) you are listed as a code owner for? Thanks!

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[frenck]

This can be useful sometimes as the time on the meter can sometimes have some offset. (12 seconds in my case now for example)

What is the practical use case of this?

[dupondje]

What is the practical use case of this?

I for example calculate the estimated peak usage according to the current peak usage + current power usage.
But the calculation goes wrong if there is some offset on the time of the dsmr meter and the real time.
Because the current peak usage will be 0 like 15sec earlier than it should (because time offset).

Only small amount of people will use it I guess, but it doesn't hurt to have it as a sensor which is disabled by default I guess?

[jbouwh]

LGTM,
Thnx @dupondje 👍

[home-assistant]

Please take a look at the requested changes, and use the Ready for review button when you are done, thanks 👍

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[frenck]

Only small amount of people will use it I guess, but it doesn't hurt to have it as a sensor which is disabled by default I guess?

I dunno honestly, this is not a common / normal pattern in our integrations, hence I think it is odd to add it here as well.

@joostlek @jbouwh You approved, does that mean you do think this is a common pattern?

../Frenck

[dupondje]

dsmr_reader has it also included for example:

core/homeassistant/components/dsmr_reader/definitions.py

Line 196 in db9d6b4

DSMRReaderSensorEntityDescription(

Just don't see a reason to enable it by default. But might be useful for some users to have it available.

[frenck]

That doesn't make it a common pattern?

[jbouwh]

dsmr_reader has it also included for example:

core/homeassistant/components/dsmr_reader/definitions.py

Line 196 in db9d6b4

DSMRReaderSensorEntityDescription(

Just don't see a reason to enable it by default. But might be useful for some users to have it available.
Some meters, especially MBUS devices post updates at a lower frequency.

[jbouwh]

@joostlek @jbouwh You approved, does that mean you do think this is a common pattern?

I have implemented this in my own environment. I see this as a common pattern. It is not enabled by default though.

[frenck]

But what is the use case for it?

[jbouwh]

But what is the use case for it?

I use it to correlate the data with my solar data. It makes sense to take a snapshot at the same timestamp.
I calculate direct consumption etc from the combined data.