Ok, got it.
I had looked at this awhile ago and it seemed inappropriate for the relatively low data volume of IoTaWatt. At the time I believe the lowest plan was the Hobby plan at $50/month. Pretty expensive hobby. If I could get $50 a month from users I’d give them the IoTaWatt. Kinda like printer ink.
I see that they now have a free plan that looks as if it would work ok, except that it only retains the data for 30 days. I suppose that’s fine for looking at recent activity and doing any longer term analysis directly with the IoTaWatt data.
There is also a pay-as-you-go plan, and I haven’t tried to estimate the cost for that. Have you looked into that?
In any event, it looks as if this service requires adding some query fields to the URL and also some method of specifying a token. I’ll have to look into that. IoTaWatt already supports the username/password authorization, so the token is something new.
It looks from the CURL example that it accepts HTTP posts. If it turns out they require HTTPS, that’s a show stopper unless you use a proxy like Nginx to translate.
I’ll take a closer look when I get some time.