misc/soliscloud-inverter-control#2: On/Off Triggering Mechanism

I think what I want to do is create functions like startCharging()/stopCharging().

These would then dynamically generate times to feed into the API

Start()

The start time would be the beginning of the current hour, effectively triggering immediately.

The end time just needs to be some time in the future, because at some point, stopCharging() will get called.

However, there are a couple of caveats here

• We should assume that the call to stopCharging() might fail, so the stop time should be a fixed amount of time (3 hours maybe?). The function should take an argument which defines how long away the stop time should be
• The inverter uses a 24h clock with no understanding of dates, so if the stop time rolls into the next day we'll need to reduce it to 23:59

Stop()

To stop charging, we need to invalidate the setting - setting it to 00:00-00:00

Catches

There are likely to be a few issues with this approach

The first that comes to mind is that fixed timings can no longer be set via the Soliscloud app/web interface.

We'll likely only use 1 time slot and there are 3, so on the face of it, they could coexist. The problem is, timeslots aren't allowed to overlap so we'd have to implement complicated logic to amend slots and account for that.

The second is that we'll be quite reliant on the Soliscloud API behaving. That's not always a given: although the API remains reachable, sometimes they fail to communicate with the inverter.

We should almost certainly implement retries to reduce the impact of this

The following function calculates the time range to use:

def calculateDynamicTimeRange(end_hours = 3):
    ''' Calculate a time range to pass into the API
    '''

    now = datetime.now()

    hour_begin = now.replace(minute=0)
    hour_end = hour_begin + timedelta(hours=end_hours)

    if int(hour_begin.strftime("%H")) > int(hour_end.strftime("%H")):
        # Time wrapped
        hour_end = hour_end.replace(hour=0)

    # Turn into a textual range
    b = hour_begin.strftime("%H:%M")
    e = hour_end.strftime("%H:%M")

    return f"{b}-{e}"

The minute will always be 00 - the end time is only intended as a safety net.

The commit above adds two functions

    soliscloud.startCharge(config, 3)
    soliscloud.stopCharge(config)

These can be used to start and stop charging. Need to add equivalents for discharge (probably tomorrow).

Surprisingly, we'll probably then be ready to look at wrapping it in a Flask app so that HomeAssistant can be told to make calls to it.

There are now 4 functions which can be called:

soliscloud.startCharge(config, 3)
soliscloud.startDischarge(config, 3)

soliscloud.stopCharge(config)
soliscloud.stopDischarge(config)

It doesn't make sense to have to keep passing config about though, so I'm going to remove that from the method signatures

Invocation is now:

soliscloud.startCharge(3)
soliscloud.startDischarge(3)

soliscloud.stopCharge()
soliscloud.stopDischarge()

The stop functions are only really separate for convenience - calling either will stop both charge and discharge.