Basic script to read data from a CurrentCost CC128 and post that data to Cosm

cosm_currentcost.py

#!/usr/bin/env python

import serial
import xml.etree.ElementTree as ET
import sys
import requests
import json
import time
import syslog

FEED_ID = 'FEED_ID'
API_KEY = 'API_KEY_WITH_UPDATE_RIGHTS_FOR_YOUR_FEED'
URL = 'http://api.cosm.com/v2/feeds/' + FEED_ID + '.json'

def read_currentcost():
  syslog.syslog("Reading data from currentcost")
  print "Reading from currentcost"
  sensor = None
  watts = None
  temp = None

  while watts == None:
    try:
      line = ser.readline()
      tree = ET.XML(line)
      watts = int(tree.findtext("ch1/watts"))
      sensor = tree.findtext("sensor")
      temp = float(tree.findtext("tmpr"))
    except Exception, inst:
      sys.stderr.write("XML error: " + str(inst) + "\n")
      line = None

  ser.flushInput()
  return sensor, watts, temp

def send_to_cosm(sensor, watts, temp):
  print "Sending to cosm"
  headers = { 'X-ApiKey': API_KEY }
  payload = { 'version': '1.0.0', 'datastreams': [ { 'id': 'temperature', 'current_value': str(temp) }, { 'id' : 'watts', 'current_value': str(watts) }, { 'id' : 'kwh', 'current_value': kwh(watts, 6) } ] }
  try:
    r = requests.put(URL, data=json.dumps(payload), headers=headers)
  except Exception, inst:
    sys.stderr.write("HTTP error: " + str(inst) + "\n")

def kwh(watts, interval):
  dividerAmount = ((60.0 / interval) * 60)
  kwh = (watts / dividerAmount) / 1000
  return "%.6f" % kwh

def run():
  print "Starting currentcost.py"

  while 1:
    sensor, watts, temp = read_currentcost()

    send_to_cosm(sensor, watts, temp)


ser = serial.Serial('/dev/ttyUSB0', 57600)
ser.timeout = 20
ser.flushInput()

run()

This is really great, I was struggling to get the data from my EnvyR to Xively, works a treat thanks.

I don't quite understand the kwh calculation what is that doing?