prometheus node_exporter digitemp text_collector

1wire_text_collector.py

#!/usr/bin/env python

# from 35c3 event, dump digitemp 1wire sensor data in prometheus text collector format
# Inspired by SuperQ's node_exporter/text_collector_examples/ntpd_metrics.py
# Author: Matt Peterson <matt@peterson.org>

import subprocess
import sys

digitemp_command = ['digitemp_DS9097U','-q','-a','-o%R %C','-c','/root/.digitemprc'] 

# iButtonLink QR code is little endian, swap digitemp output
def big2little(string):
    t = bytearray.fromhex(string)
    t.reverse()
    return ''.join(format(x,'02x') for x in t).upper()

def get_output(command):
    try:
        output = subprocess.check_output(command)
    except subprocess.CalledProcessError as e:
        return None
    for line in output.decode().split('\n'):
        sensor_serial = big2little(line.rstrip().split(' ')[0])
        reading_celsius = line.rstrip().split(' ')[1]
        return "digitemp_DS9097U_sensor{address=\"" + sensor_serial + "\"} " + reading_celsius

if __name__ == "__main__":
    print get_output(digitemp_command)