Get Started with Voice Survey using Python

To implement Voice Survey use-case in the traditional API/XML way, you can refer to the instructions in the below section to begin your implementation.

Outline

Implementation

In this section, we will guide you in setting up an app using Plivo’s API/XML to implement Voice Survey use-case. First, let’s make sure you meet these prerequisites before we dive into the code.

Prequisites

1. Create a Plivo Account(if you don’t have one already): You can sign up with your work email address and complete the phone verification step using your mobile number.
2. Set up your dev environment: To set up your dev environment in your preferred programming language, please refer to the instructions available in the Setting up the Dev Environment Guides.
3. Buy a Plivo number(optional): You must have a voice-enabled Plivo phone number if you are willing to receive incoming calls. You can purchase numbers from the Numbers section of your Plivo Console. It is also possible to purchase numbers using the Numbers API.

Prerequisites

This section will guide you through how to use Plivo APIs to make voice calls from your application. First, let’s make sure you meet these prerequisites before we dive into the code.

• Plivo Auth Id and Auth Token: You will find your Plivo Auth Id and Auth Token on the home screen of your Plivo Console. Click here to sign-up for a Plivo account if you haven’t already!

  

• Plivo Phone Number(Optional): You can purchase numbers from the Numbers section of your Plivo Console and use the same as the caller ID for the outbound call. This number will also help you receive incoming calls as you must have a voice-enabled Plivo phone number to do the same. Please note that you can also purchase numbers using the Numbers API.

  

• Answer Url: When a call is answered by the destination_number, you can control the call flow with the help of the answer_url set in the API request. Plivo will invoke the answer_url specified as soon as the call is answered and expect a valid XML response with instructions to handle the call. In addition to requests to the answer URL, Plivo initiates HTTP requests to your application server through the course of a call based on the specific XML elements in your answer XML. Such requests can be broadly classified into two categories:

  Action URL requests: XML instructions to carry forward the call are expected in response to these requests. These requests are typically invoked at the end of an XML element’s execution. For example: when an IVR input is received from the caller during a GetInput XML execution.

  Callback URL requests: No XML instructions are expected in response to these requests. Such requests serve as webhooks to notify your application server of important events through the course of an XML element’s execution. For example: when a conference participant is muted or unmuted.

Set up Your Python Dev Environment

You must set up and install Python and Plivo’s Python SDK implement Voice Survey use-case. Here’s how.

Install Python

Install Plivo Python Package

• Create a project directory, run the following command:

  $ mkdir mypythonapp
  

• Change the directory to our project directory in the command line:

  $ cd mypythonapp
  

• Install the SDK using pip

  pip install plivo
  

• Alternatively, you can download the source code from this repo and run

  python setup.py install
  

We recommend that you use virtualenv to manage and segregate your Python environments, instead of using sudo with your commands and overwriting dependencies.

Create the Outbound Call App

Once you have the above prerequisites set, You can follow the below instructions to create an app to implement Voice Survey use-case and redirect the call to an Automated Voice Survey IVR using a GetInput XML once the call recipients answer the call.

Now, create a file called broadcast.py and paste the below code.

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import plivo

client = plivo.RestClient()
response = client.calls.create(
    from='+14151234567',
    to='+14157654321<+14157654321',
    answer_url='https://s3.amazonaws.com/static.plivo.com/broadcast.xml',
    answer_method='GET', )
print(response)

Create a Flask App to Implement Phone System IVR

Use the following code snippet to start a local server.

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# -*- coding: utf-8 -*-
from flask import Flask, Response, request, url_for
from plivo import plivoxml

# This is the message that Plivo reads when the call recipient answers the call.
question1 = "Hi, this is a call from Plivo, How would you rate your overall satisfaction with our services? Press 1 if you are satisfied or Press 2 if you would like to suggest any improvements."
question2 = "How would you rate your satisfaction with our customer service. Press 1 for English. Press 1 if you are satisfied or Press 2 if you would like to suggest any improvements. Thanks!"
# This is the message that Plivo reads when the recipient provides negative feedback
negative_feedback = "We are sorry about your bad experience, One of our representatives will get in touch with you shortly."
# This is the message that Plivo reads when the caller does nothing at all
noinput_message = "Sorry, I didn't catch that. Please hangup and try again \
                    later."
# This is the message that Plivo reads when the caller inputs a wrong number.
wronginput_message = "Sorry, it's wrong input."

app = Flask(__name__)

@app.route('/survey/', methods=['GET','POST'])
def ivr():
    response = plivoxml.ResponseElement()
    getinput_action_url = "http://www.foo.com/firstbranch/"
    response.add(plivoxml.GetInputElement().
        set_action(getinput_action_url).
        set_method('POST').
        set_input_type('dtmf').
        set_digit_end_timeout(5).
        set_redirect(True).add(
            plivoxml.SpeakElement(question1)))
    response.add(plivoxml.SpeakElement(noinput_message))
    return Response(response.to_string(), mimetype='application/xml')

@app.route('/survey/firstbranch/', methods=['GET','POST'])
def firstbranch():
    response = plivoxml.ResponseElement()
    digit = request.values.get('Digits')
    if digit == "1":
        # Read out a text.
        getinput_action_url = "http://www.foo.com/secondbranch/"
        response.add(plivoxml.GetInputElement().
            set_action(getinput_action_url).
            set_method('POST').
            set_input_type('dtmf').
            set_digit_end_timeout(5).
            set_redirect(True).add(
                plivoxml.SpeakElement(question2)))
        response.add(plivoxml.SpeakElement(noinput_message))

    elif digit == "2":
        response.add_speak(negative_feedback)

    else:
        response.add_speak(wronginput_message)
    return Response(response.to_string(), mimetype='application/xml')

@app.route('/ivr/secondbranch/', methods=['GET','POST'])
def secondbranch():
    response = plivoxml.ResponseElement()
    digit = request.values.get('Digits')

    if digit == "1":
        text = u"Thank you for participating in the survey!"
        params = {
            'language': "en-GB",
        }
        response.add_speak(text,**params)

    elif digit == "2":
        response.add_speak(negative_feedback)

    else:
        response.add_speak(wronginput_message)
    return Response(response.to_string(), mimetype='application/xml')

if __name__ == '__main__':
    app.run(host='0.0.0.0', debug=True)

Save this code in any file (name the file something like survey.py). To run this file on the server, go to the folder where this file resides and use the following command:

$ python survey.py

And you should see your basic server app in action on http://localhost:5000/survey/

Exposing your local server to the internet

To receive Incoming Calls and to handle callbacks, your local server should be able to connect with Plivo API service, Ngrok is a tunneling software used to expose a web server running on your local machine to the internet. Using Ngrok you can set webhooks which can talk to Plivo server.

You can download and install ngrok from here. Follow the detailed configuration instructions to get started.

Run ngrok on the port which currently hosts your application. For example, if your port number is 8000, run the following command:

./ngrok http 8000

This will give you a UI with links that look like ngrok.io/* which you can use to access your local server using the public network.

You can check the app in action on https://6ea358b0f703.ngrok.io/survey/.

Test and Validate

Once you have created the Outbound Call App, save the file and use the below command to run your code.

$ python broadcast.py