Conference On Demand With Twilio and PHP

One of the coolest things about having your own phone number with Twilio (Twilio.com). Is that you can do some very nifty things with it.

For example, if you need a conference room setup with a text message you can forward to your friends, you can configure this in a PHP script quite easily, we can even get the script to respond to your request with details about the number to ring and the pin code.

If you haven’t already done so, head over to Twilio¬†(Twilio.com) an sign up at: Try-Twilio This will provision you a Twilio number that you can call into and interact with.

Once we have a number lets build a script that can respond to our SMS message, generate the conference room pin and then respond back with the details of our conference room.

<?php

// Incoming Voice number thats paired with this setup – used for voice Conferences etc.
$voiceNumber = “+1…”;

// Get the Variables from the HTTP POST, We want to know the BODY and the FROM so we can authorise and action the request.

$fromPhoneNumber = $_POST[“From”];
$messageBody = $_POST[“Body”];

// Check the phone number is on our authorised list if so action the SMS request.

// As this grows I want to put the numbers into an authorised DB and make a DB request regarding this.
// As this minute we are just going to look up against authorised number just in the IF field.

if ($fromPhoneNumber == “+1…” or “+44…”) // This is the list of authorised numbers that can make conf rooms.

{

// If the number is authorised then we are going to look at the body for what we need to make / do.

if ($messageBody == “Conference” or “Conf”)
{
// If the body is Conference we want to generate a 4 digit pin number and then generate a SMS message that can be
// forwarded out to the participants.

// The idea is that this script will reply with
// “A Conference has been setup, please call XYZ Number press option X and enter pin abcd”

$confPin = rand(1000, 9999); // Generate a random pin number
$TwiMLResponse = “<Message>Conference Room Details:\r\nPhone Number: ” . $voiceNumber . “\r\nConference Pin: ” . $confPin. “</Message>”;
}
else // Catch all for whats left.
{
$TwiMLResponse = “<Message>Sorry, Me No understand. Try Again.</Message>”;
}
}
else
{
$TwiMLResponse = “<Message>Sorry, Your not authorised for this.</Message>”;
}

header(“content-type: text/xml”);
?>

<Response><?php echo $TwiMLResponse; ?></Response>

This script will check that the inbound number is able make conference room pin numbers and if so will generate a 4 digit pin that will then be distributed back to the user.

Now when we text our number the body “Conference” or “Conf” from an authorised phone it will generate a pin number and respond back with details of the conference room in a SMS message:

 

Conf Details

Conference Room Details

 

You can then copy and paste this SMS message into a group SMS or Whatsapp and allow people to call into the conference room.

Now we have the SMS part setup we need to build a script that can welcome the caller, get the pin number and then route them to the correct conference based on that response.

<?php

// Check to see if a Conf Pin has been inputted. If so, make a Conf room with that pin.
$confPin = $_GET[“Digits”];

// If no conf Pin ask the caller to enter a Conf pin or else hangup.
if (isset($confPin)){
$TwiMLResponse = “<Say voice=\”alice\”>Placing You into Conference Now.</Say><Dial><Conference>”. $confPin .”</Conference></Dial>”;
}
else
{
$TwiMLResponse = “<Gather method=\”GET\” timeout=\”25\” numDigits=\”4\”><Say voice=\”alice\”>Hello and welcome to the conference line. Please enter the Conference Pin.</Say></Gather><Say>I’m Sorry I didnt catch that</Say>”;

}

header(“content-type: text/xml”);
?>

<Response><?php echo $TwiMLResponse; ?></Response>

 

Here in this script we are checking to see if the GET method has been passed with any digits, indicating that the caller has already been greeted and input a conference pin. If we have a conference pin then we can use the digits to put his caller into that conference room.

 

This is a very simple conference line setup tool, and it will need some further modifying to make it secure. For example right now any 4 digit numbers will create a conference room. You may wish to modify the code so that only generated pin numbers can be used and those numbers cannot be reused – entirely up to you.