Placing a call with Twilio and Python 2.7

Introduction

Twilio allows to do many things. Here I'm interested in placing a sample call to a fixed line, using Python 2.7 - alias I cannot used Twilio's helper Python library which is Python 3 only.

So I'm going to rely instead on the excellent requests library.

The first step are to:

• Get a Twilio test account
• Request a test phone number
• Identify my API Secret and Keys
• Whitelist my target phone number

The program bellow will then place a call, and query a number of times for the status of the call.

The code

#!/usr/bin/python

import requests
from requests.auth import HTTPBasicAuth
import time
from xml.etree import ElementTree


API_KEY = 'AC....'
API_SECRET = 'a4...'

CALLING_NUMBER = '+41....'
CALLED_NUMBER = '+41....'

XML_URL = 'http://demo.twilio.com/docs/voice.xml'

BASE_URL = 'https://api.twilio.com/'
POST_URL = '%s/2010-04-01/Accounts/%s/Calls' % (BASE_URL, API_KEY, )

SLEEP_DELAY = 2     # Seconds
NB_POLLS = 10

auth = HTTPBasicAuth(API_KEY, API_SECRET)

r = requests.post(
    POST_URL,
    auth=auth,
    data={
        'From': CALLING_NUMBER,
        'To': CALLED_NUMBER,
        'Url': XML_URL,
    },
)

tree = ElementTree.fromstring(r.text)

call_uri = tree.find('.//Uri')
if call_uri is not None:
    STATUS_URL = BASE_URL + call_uri.text
    for i in range(NB_POLLS):
        r = requests.get(STATUS_URL, auth=auth)
        tree = ElementTree.fromstring(r.text)
        status = tree.find('.//Status')
        if status is not None:
            print status.text
        time.sleep(SLEEP_DELAY)