Log ZCell state of charge

zcell-soc.sh

#!/bin/bash
#
# Polls the ZCell BMS REST API once per minute and prints the
# current state of charge.  Runs indefinitely.
# Requires `curl` and `jq`.
# 
# Note: this only looks at the first battery in the system
# (".list[0]" in the `jq` invocation).
#

if [ -z "$1" ]; then
	echo "Usage: $(basename $0) BMS_IP [POLL_INTERVAL]"
	exit 1
fi

STATUS_URL="http://${1}:3000/rest/1.0/status"
INTERVAL="${2:-60}"
LAST=""

echo "Polling ${STATUS_URL} at ${INTERVAL} second intervals"
while true ; do
	curl -s ${STATUS_URL} | jq -r '.list[0].state_of_charge'
	sleep $INTERVAL
done