collectd python plugin for evohome

evohome.py

# collectd python plugin for evohome
# Copyright 2015 Robert McQueen <robert@mcqueen.me.uk>
# GNU General Public License v2 or later, no warranty etc
# 
# uses https://github.com/watchforstock/evohome-client to read temperatures and setpoints
# could be more smart in terms of keeping credentials and refreshing them when they time out rather than logging in every time
# supports multiple evohome devices
# ignores hot water
# patches welcome :)

import collectd
import evohomeclient2

USERNAME = 'xxx'
PASSWORD = 'yyy'

def scrub(s):
    return ''.join([ c.lower() if c.isalnum() else "_" for c in s ])

def dispatch_location(name, cs):
    vals = collectd.Values()
    vals.plugin = 'evohome'
    vals.plugin_instance = scrub(name)
    vals.type = 'temperature'

    for zone in cs.temperatures():
        if zone['thermostat'] != 'EMEA_ZONE':
          continue

        name = 'zone_' + scrub(zone['name'])

        vals.type_instance = name + '_setpoint'
        vals.values = [float(zone['setpoint'])]
        vals.dispatch()

        if zone['temp'] is None:
          continue

        vals.type_instance = name + '_temp'
        vals.values = [float(zone['temp'])]
        vals.dispatch()

def plugin_read(input_data=None):
    global USERNAME, PASSWORD

    client = evohomeclient2.EvohomeClient(USERNAME, PASSWORD)

    for loc in client.locations:
        dispatch_location(loc.name, loc._gateways[0]._control_systems[0])

collectd.register_read(plugin_read)

collectd config needs something like

<Plugin python>
ModulePath "/etc/collectd/python"
LogTraces true
Import "evohome"
</Plugin>