Add iotawatt high-accuracy energy readout sensors

[jyavenard]

There were previously two types of sensors: current and energy. The current reads the value that is the average of the last 30s
And the energy which is the amount in Wh since the January 1st of the current year.

Due to how the iotawatt performs calculation internally, the energy sensors only works with outputs that use a limited set of mathematical operation (e.g. only + and -). More complex ones, such as what you would use to calculate the net energy export and import if you had a net solar system, will read wrong (and read 0 for export).

This change adds an extra energy sensor, with an " Accumulated" suffix that will read the last 30s of energy used or produced and progressively add to a permanent counter. This counter would typically always monotically increase or decrease.

In order to prevent data from being lost when the iotawatt becomes inaccessible or when the HA instance is offline (such as during an update), the sensor will fetch the missing data from the iotawatt since the last known update upon restart.

This requires the iotawattpy 0.1.0 version which was just released.

Fly-by fix: remove unused name ad mac_address IotaWattSensor parameters.

Breaking change

None.
This only adds a new sensors to the existing iotawatt integration. They will be automatically added once HA is restarted.

Proposed change

The iotawatt integration doesn't allow to correctly read energy sensors due to the way the iotawatt process the request.
A summary of the problem is in the comment above.

For more details the issue is as follow:
Assume we have defined an output in the iotawatt UI to calculate import and export power from/to the grid.
The calculation would be:
Export = (Consumption+Production) min 0
Import = (Consumption+Production) max 0
where Production is a negative number as the current flows out.

When the current integration queries the energy force those sensors, it does so by requesting the energy value since January 1st of the year.
the iotawatt device will calculate it this way:
Export = (Average(Consumption, period) + Average(Consumption, period)) * duration_in_hour

rather than running the expression on the individual measurements. The reason for this is the lack of processing power by the iotawatt and the slow access speed to the storage medium.

So imagine you power load is a constant 1000W since the beginning of the year. a total of 1kw * 243 days * 24 = 5832kWh
and today you installed a solar system that produced 2000W for 1h; a total of -2kWh since January 2021.

If you query the iotawatt it will then return:
min(0, 5832kWh + -2kW) = 0

When obviously the correct was 1kWh (the excess power was 1000W over an hour)

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue: I didn't open a bug.
• Link to documentation pull request:

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[probot-home-assistant]

Hey there @gtdiehl, mind taking a look at this pull request as it has been labeled with an integration (iotawatt) you are listed as a code owner for? Thanks!
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[bdraco]

Thank you for your contribution thus far! 🎖 Since this is a significant contribution, we would appreciate you'd added yourself to the list of code owners for this integration. ❤️

Please, add your GitHub username to the manifest.json of this integration.

For more information about "code owners", see: Architecture Decision Record 0008: Code owners.

[bdraco]

LGTM 👍