Add caching layer for inverters that go offline after dark

[robbinjanssen]

We've learned that some inverters go offline after dark. Meaning the status.js/json file is no longer reachable. Instead of throwing errors and exceptions we would like to introduce a caching layer. As discussed in the python client for this package we need to add the caching layer to this integration.

@sander76 reached out and pointed us in the right direction. Unfortunately I don't have much time right now, it would be awesome if anyone would like to give it a go!

Instructions here:
klaasnicolaas/python-omnikinverter#24 (comment)

This would solve #39

[klaasnicolaas]

Let's sign this up for hacktoberfest 😄

[ronaldt80]

@klaasnicolaas is there any way to correct faulty values in the long-term statistics database?
I have 2 inverters, 1 went briefly offline and back online twice today. Result is that HA Energy showed 13,000kwh production today. The previous integration had caching on so never experienced this issue before. Will probably roll back to v1 until caching is possible in V2 as well but in the meantime would be good to correct the incorrect data.

[klaasnicolaas]

Yes there is a service that I think you can use to remove incorrect data.

Regarding your issue, it is interesting to see what your inverter does after going offline and coming back online. An interruption is not bad, but it is when a 0 is passed as a value from the inverter. Can you indicate which data source you are using? Contact me via a DM in Discord (Mister Nicolaz#7558), so we can check some things.

[ELANDJEA]

@klaasnicolaas is there any way to correct faulty values in the long-term statistics database? I have 2 inverters, 1 went briefly offline and back online twice today. Result is that HA Energy showed 13,000kwh production today. The previous integration had caching on so never experienced this issue before. Will probably roll back to v1 until caching is possible in V2 as well but in the meantime would be good to correct the incorrect data.

I have seen the same happening within my environment. to me it feels like the energy_total sensor does have an issue with the "last_reset" property. As if that property is interpreted as reset today instead of long-long-timeago. In my situation it showed 13000 KwH on day one and day two it started with 26000 KwH (+ a little) within the daily energy meter.....I did not wait for the 3rd day......
I switched over to the "energy_today" property for the energy dashboard, which now acts normally for about 3 days already. (due to the daily start with 0 I asume).
@klaasnicolaas I suggest to also look into the "last_reset" property that might result in the high daily readings in the dashboard. (I am not a devoper....but like the new version of the omnik plugin..working nicer than the previous version)

[klaasnicolaas]

As stated before, this has to do with your inverter sending incorrect values at certain times (we have seen this on JSON source). To determine this for sure, we need to apply some extra logging so that we can figure this out. The last_reset has nothing to do with it, it only assumes that there has been a reset due to a decreating in the total_increasing.

What source do you use and could you access it privately so we can debug this further?

[ELANDJEA]

I used the JS source for getting the data. (http:///js/status.js)
if needed I can get output from that source.....guess one time output is not enough....you need at least a certain sequence?

[robbinjanssen]

Could you please open a separate issue for this, as this is something different than the caching issue :-)

[wes1993]

We have some news about this implementation?

[robbinjanssen]

Unfortunately not, currently i dont have much spare time. But i'm happy to accept a PR! :)