DTMF XML

The DTMF element is used to send digits on a live call. This will usually be used to automate the process of navigating through an external phone tree (IVR).

Digits are sent in the background when the async parameter is set to true, so the call will jump to the next XML element when the first digit is sent. Use the character w for a 0.5 second delay and the character W for a 1 second delay. Allowed values: 1234567890*#wW

Prerequisites

Sign up for a free Plivo trial account.
Check out our server-side SDKs page and install the right helper based on the programming language you want to use.
Buy a Plivo phone number. A phone number is required to receive calls. You can buy a Plivo phone number in over 20+ countries through the Buy Numbers tab on your Plivo account UI. Check the Voice API coverage page for all the supported countries.
Use a web hosting service to host your web application. There are many inexpensive cloud hosting providers that you can use for just a few dollars a month. Follow the instructions of your hosting provider to host your web application.

Set up a Web Server

Let’s assume your web server is located at example.com. Below is a snippet to set up a route on your webserver. Lets call it, /dtmf/. Now when we send an HTTP request to example.com/dtmf/ this route will be invoked.

Note: For PHP, the route will be example.com/dtmf.php.

Copy the relevant code below into a text file and save it. Lets call it, dtmf.
Note: Make sure to use the appropriate file extention for your code (e.g., .py for Python).
Now that you have the code, you will need to expose your server to the public Internet. This way, Plivo will know where to find your app when a particular phone number is dialed. Moving forward, we will assume that your app is available at example.com.

Code

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import plivoxml
from flask import Flask, Response

app = Flask(__name__)

@app.route('/dtmf/', methods=['GET','POST'])
def dtmf():
    r = plivoxml.Response()
    r.addSpeak("Sending Digits")
    r.addDTMF("12345")
    print r.to_xml()
    return Response(str(r), mimetype='text/xml')

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

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require 'rubygems'
require 'sinatra'
require 'plivo'
include Plivo

get '/dtmf/' do
    r = Response.new()
    r.addSpeak("Sending Digits")
    r.addDTMF("12345")

    puts r.to_xml()
    content_type 'text/xml'
    return r.to_s()
end

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var plivo = require('plivo');
var plivo = require('plivo');
var express = require('express');
var app = express();

app.set('port', (process.env.PORT || 5000));
app.all('/dtmf/', function(request, response) {
  var r = plivo.Response();
  r.addSpeak("Sending Digits");
  r.addDTMF("12345");
  console.log (r.toXML());
  response.set({'Content-Type': 'text/xml'});
  response.send(r.toXML());
});

app.listen(app.get('port'), function() {
    console.log('Node app is running on port', app.get('port'));
});

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<?php
    require 'vendor/autoload.php';
    use Plivo\Response;
    $r = new Response();
    // Add Speak tag
    $body = "Sending Digits";
    $r->addSpeak($body);
    // Add DTMF tag
    $dtmf = "12345";
    $r->addDTMF($dtmf);
    Header('Content-type: text/xml');
    echo($r->toXML());

?>

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package plivoexample;

import java.io.IOException;

import com.plivo.helper.exception.PlivoException;
import com.plivo.helper.xml.elements.Dtmf;
import com.plivo.helper.xml.elements.PlivoResponse;
import com.plivo.helper.xml.elements.Speak;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.servlet.ServletContextHandler;
import org.eclipse.jetty.servlet.ServletHolder;

public class dtmfXml extends HttpServlet {
    private static final long serialVersionUID = 1L;
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {

        PlivoResponse response = new PlivoResponse();
        Dtmf dt = new Dtmf("12345");
        Speak speak = new Speak("Sending digits");

        try {
            response.append(speak);
            response.append(dt);
            System.out.println(response.toXML());
            resp.addHeader("Content-Type", "text/xml");
            resp.getWriter().print(response.toXML());;
        } catch (PlivoException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) throws Exception {
        String port = System.getenv("PORT");
        if(port==null)
            port ="8000";
        Server server = new Server(Integer.valueOf(port));
        ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);
        context.setContextPath("/");
        server.setHandler(context);
        context.addServlet(new ServletHolder(new dtmfXml()),"/dtmf/");
        server.start();
        server.join();
    }
}

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using System;
using System.Collections.Generic;
using System.Diagnostics;
using RestSharp;
using Plivo.XML;
using Nancy;

namespace custom_tone
{
    public class Program : NancyModule
    {
        public Program()
        {
            Get["/dtmf/"] = x =>
            {
                Plivo.XML.Response resp = new Plivo.XML.Response();

                // Add Speak XML Tag
                resp.AddSpeak("Sending digits", new Dictionary&lt;string, string&gt;() { });

                // Add DTMF XML Tag
                resp.AddDTMF("12345", new Dictionary&lt;string, string&gt;() { });

                Debug.WriteLine(resp.ToString());

                var output = resp.ToString();
                var res = (Nancy.Response)output;
                res.ContentType = "text/xml";
                return res;

            };
        }
    }
}

Create an Application

Create an Application by visiting the Application Page and click on New Application or by using Plivo’s Application API.
Give your application a name. Lets call it DTMF XML. Enter your server URL (e.g., http://www.example.com/dtmf/) in the Answer URL field and set the method as POST. See our Application API docs to learn how to use our API to modify your application.
Click on Create to save your application.

Assign a Plivo number to your app

Navigate to the Numbers page and select the phone number you want to use for this app.
Select DTMF XML (name of the app) from the Plivo App dropdown list.
Click on ‘Update’ to save.

Create DTMF XML Application

If you don’t have a number, go to the Buy Number page to purchase a Plivo phone number.

Test it out

When you make a call to your Plivo number, the call will be answered by Plivo and the message will be played.

Sample XML

<Response>
    <Speak>Connecting your call..</Speak>
    <DTMF>12345</DTMF>
</Response>

Next Step

Learn how to set Dynamic Caller ID.