Xively: how to activate a device with the python api?

Question

Since COSM has become Xively, a nice device api has been added (or was always there- not sure). The flow is

1. create product batch with serial numbers
2. activate devices using some product batch identifiers (?)
3. start using the device with the obtained feed/api keys

I can't figure out how to do this via the python API- are there any pointers?

Answer 1

This should be added to the library, but for now you can use this code to implement device activation. I have used environment variables to store product secret and device serial, but change that for anything that suites your use case. The only tricky part is that you need to call a2b_hex().

import xively

from os import environ    
from hashlib import sha1
from binascii import a2b_hex
import hmac

secret = environ['XIVELY_PRODUCT_SECRET']
serial = environ['XIVELY_DEVICE_SERIAL_NUMBER']

activation = hmac.new(a2b_hex(secret), serial, sha1).hexdigest()

creds = xively.Client(key=None).get('/v2/devices/'+activation+'/activate').json()

xi_feed = xively.XivelyAPIClient(creds['apikey']).feeds.get(creds['feed_id'])

You will also need take care to store the credentials into a file, as a device can be activated only once. You will notice 403 errors if you try to run this code again and again, so do use the Xively developer workbench for deactivating the device under test (you may need to refresh the page).

Here is a fully working example using config files or environment variables:

#!/usr/bin/python

from os import environ 
from hashlib import sha1 
from binascii import a2b_hex 
import hmac
import sys, subprocess
import ConfigParser
import xively

CONFIG_FILE = 'xively.conf'

PROVISIONING = 'PROVISIONING'

PROVISIONING_PRODUCT_SECRET = 'PRODUCT_SECRET'
PROVISIONING_DEVICE_SERIAL = 'DEVICE_SERIAL'

PROVISIONING_FEED_ID = 'FEED_ID'
PROVISIONING_API_KEY = 'API_KEY'

def get_setting(config, section, key):
    try:
    value = config.get(section, key)
    except:
    print key + " not found in config file. Using environment variable " + key + " instead."

    try:
        value = environ[key]
    except:
        print key + " not found in environment."
        raise
    # value defined?
    if not value:
    raise
    return value

def xively_activate_product(secret, serial):
    activation = hmac.new(a2b_hex(secret), serial, sha1).hexdigest()
    creds = xively.Client(key=None).get('/v2/devices/'+activation+'/activate').json()
    return creds 

# main
config = ConfigParser.RawConfigParser()
config.read(CONFIG_FILE)

try:
    # see if we already have an api key and feed id
    feed_id = config.get(PROVISIONING, PROVISIONING_FEED_ID)
    api_key = config.get(PROVISIONING, PROVISIONING_API_KEY)

    print "Provisioned product details:"
    print "FEED_ID: " + str(feed_id)
    print "API_KEY: " + api_key

    # continue working with your activated product here

except:
    print "FEED_ID and API_KEY not found. Activating product now."

    # no error handling for secret- it _is_ needed
    try:
    secret = get_setting(config, PROVISIONING, PROVISIONING_PRODUCT_SECRET)
    except:        
    print "Finding " + PROVISIONING_PRODUCT_SECRET + " failed. Giving up."
    sys.exit(1)

    try:
    serial = get_setting(config, PROVISIONING, PROVISIONING_DEVICE_SERIAL)
    except:        
    serial = subprocess.check_output("hostname", shell=True)
    if not serial:
        print "Fallback to hostname for " + PROVISIONING_DEVICE_SERIAL + " failed. Giving up."
        sys.exit(1)

    try:    
    creds = xively_activate_product(secret, serial)

    # check if there were errors
    try:
        creds["errors"]
    except:
        pass
    else:
        print "Product activation failed (" + creds["title"] +": "+ creds["errors"] + ")."
        sys.exit(1)

    feed_id = creds['feed_id']
    api_key = creds['apikey']

    print "Product activation successful."
    print "FEED_ID: " + str(feed_id)
    print "API_KEY: " + api_key

    if not config.has_section(PROVISIONING):
        config.add_section(PROVISIONING)

    config.set(PROVISIONING, PROVISIONING_FEED_ID, feed_id)
    config.set(PROVISIONING, PROVISIONING_API_KEY, api_key)

    # Writing our configuration file to 'example.cfg'
    with open(CONFIG_FILE, 'wb') as configfile:
        config.write(configfile)

    except Exception as e:
    print "Product activation failed (" + str(e) +")."
    sys.exit(1)