I have an ESP8266 I wanted to use to with an INA219 chip as the voltage and current monitor for my toy solar panel array. The logged data can be visualized for curiosity, or maybe analyzed and that information fed into something in the future. I started with Arduino IDE, then moved to ESP-IDF on an ESP32, and most recently I played with MicroPython. This was a fun trip exploring the foundational elements, but looking towards the future I see a lot of software work to build this into a system and my interest started to fade.

What if somebody else has already built the infrastructure for something like this? Well, since I was on Adafruit's INA219 page I saw that they had built one called Adafruit IO. Right up on the landing page it says: "We do the hard work so you can focus on the fun stuff." Hey, I like the sound of that!

And in typical Adafruit fashion, they have great support for the product interoperating with a wide range of hardware. Including the ESP8266 and INA219! (Though via the Arduino platform and not their CircuitPython platform as they've dropped support for ESP8266 CircuitPython.) Data is logged, stored, easy dashboards for visualization, and that data feeds into programmable triggers to take action in response to date. Everything I foresaw having to build but is already here and ready to go. And the price is reasonable: free to start with limited functionality, and $10/mo to upgrade for full functionality.

This looks amazing but I decided against it, because I wanted something purely for consumption at home. I wouldn't call myself averse to internet applications. After all, I've put all my code on GitHub and my project notebook is publicly readable. (You're reading it right now.) Running some things on the internet makes sense when the intent is for access from anywhere, but for my home projects I don't want that data to leave the house.

Also, Adafruit IO only retains data for a limited time period. From what I can see this was 30 days during the beta and the duration is something they reserve the right to change. I can't seem to find their current data retention policy but it really doesn't matter. Their target usage scenario is for "right now" interaction and projects like long-term historical tracking and analysis is out of scope. I want the option to store that data for longer, and to do it at home, so I passed on Adafruit IO and started looking for another solution.