Use the internal ADC of the esp8266 to read light intensity from a Cadmium sulfide sensor.
tl;dr: Get rrdtool and python bindings, create a round robin DB yourself
sudo apt install rrdtool
sudo apt install python-rrd
rrdtool create ldr_data.rrd --step 60 DS:light:GAUGE:600:0:320 RRA:MAX:0.5:1:1080
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