I created the http_listener_v2 Telegraf input plugin to monitor solar panels because I wanted more access to how much power and energy my solar panels were generating, as well as correlate this data with temperature, cloudiness, and sun intensity. I was using Fronius solar inverter which sends HTTP POST requests with JSON encoded data to an endpoint, but the InfluxDB metrics collection agent Telegraf didn't support parsing JSON data at that time. Therefore, I created a plugin to extend its capabilities and persist the inverter-produced data in InfluxDB.