Add start and end time attributes

[rianadon]

The PR adds start_time and end_time attributes to washing machines, which indicates what time of day the washer started running & what time it will end.
It is similar to the same attributes used in the OpenSprinler custom integration.

This attribute is helpful for the Timer Bar Card (disclosure: my own card), which uses the start time to display the time the washer is scheduled to run. The card prefers using timestamps rather than a hh:mm offset because the hh:mm format requires the entity to update its state every minute to give a new hh:mm estimate, whereas the start time timestamp will change much less often.

I don't have an LG washer so have not been able to test whether the code is bug free or whether taking the current time + reserve time - initial time + remaining time is the correct way to calculate the start time.

See also: rianadon/timer-bar-card#70

[ollo69]

Hi @rianadon,

I know your card, really useful and also referred here by read-me (I'm also using your card). But is this PR really required? I do no like so much the idea to add additional attribute (this integration have really lot) to provide duplicated information. There is really a benefit with this?

[rianadon]

Hey @ollo69. I'd ask the same question if I were you, and you're right to be concerned this is adding extra attributes.

I tried to explain my motivation in the previous comment, but I'll explain in more detail. The main motivation behind the PR is that there are multiple ways of specifying a start time for a timer.

One way is to give a timestamp (date + time). This method is used by official Home Assistant components: BMW Connected Drive, Home Connect, and SmartThings as well as custom ones: the OpenSprinkler custom integration and Alexa media player timers. Aside: There still is a lot of variation in these integrations: some place the start time in the attributes, others as a separate entity, and some make the end time the entity's state. But the format of these start/end times are all timestamps.

The second is to give a time offset, such as a time in the hh:mm like your card does, to show how much time is remaining before the timer begins. I haven't seen this method used anywhere else, but I'm receptive to being shown examples.

Ideally, there would be a single standard for specifying start times. Consistent attributes & formats make it easier to port automations & templates from one integration to another. For me personally that would keep the code for my card simple. And all engineers love standards :) Due to the timestamp method's higher adoption and better technical performance (which I discussed in my original comment), I suggest that the standard be using timestamps for the start time.

Yes, that does add two extra attributes to your integration. I certainly would not want to replace the existing remaintime and reservetime attributes in case someone is using them for automations or templates. However, template writers may find the start_time and end_time timestamps to be easier to work with as they can easily be parsed into datetime objects. And using timetamps for start/end times will create more consistency between this integration and the other integrations out there. Hope that helps!

I know your card, really useful and also referred here by read-me (I'm also using your card).

And I appreciate the praise 😄. Thank you for maintaining such a great-quality integration.

[ollo69]

@rianadon,

This is merged now. I did a little change post merge, using the date from HomeAssistant dt_util package. This set the correct timezone to the date and allow proper conversion in HA UI.