Dialing Fallback with Twilo - twilio

Question

I am working on my inbound TwiML. At one point I want to attempt to forward a call to my cell phone number.
So I got 5555555555 but I want to redirect to a different TwiML script if there is no answer or no human answer. For example if I do not answer and Twilo gets my Cell VM, I would instead want to have Twilo try someone else in another TwiML script rather than let them leave a message on my personal VM.
I know I can set it up so I have to press 1 to connect the call, then I am assuming if I don't press 1 it would continue processing the TwiML after is this possible without requiring me to press 1?

Answer 1

Joel from Twilio here.
The best way to do what you want is to use the call screening process that you describe ("press 1 to connect the call"). This is because automatically detecting voice mail is a very error prone process.
We have an in-depth Call Screening HowTo on how to do this. Here's the overview:
Create a file called "attempt_call.php" on your web server that contains the following code (pay particular attention to the $numbers array on line 4):
<?php
// Set the numbers to call
$numbers = array("<number to call 1>", "<number to call 2>", "<number to call n>");
$number_index = isset($_REQUEST['number_index']) ? $_REQUEST['number_index'] : "0";
$DialCallStatus = isset($_REQUEST['DialCallStatus']) ? $_REQUEST['DialCallStatus'] : "";
header("content-type: text/xml");
// Check the status of the call and
// that there is a valid number to call
if($DialCallStatus!="completed" && $number_index<count($numbers)){
?>
<Response>
<Dial action="attempt_call.php?number_index=<?php echo $number_index+1 ?>">
<Number url="screen_for_machine.xml">
<?php echo $numbers[$number_index] ?>
</Number>
</Dial>
</Response>
<?php
} else {
?>
<Response>
<Hangup/>
</Response>
<?php
}
?>
Next, in the same location as the "attempt_call.php" file, create a file called "screen_for_machine.xml" with the following content:
<?xml version="1.0" encoding="UTF-8"?>
<Response>
<Gather action="complete_call.xml">
<Say>Press any key to accept this call</Say>
</Gather>
<Hangup/>
</Response>
Then, in the same location as the "attempt_call.php" file, create a file called "complete_call.xml" that contains the following:
<?xml version="1.0" encoding="UTF-8"?>
<Response>
<Gather action="complete_call.xml">
<Say>Press any key to accept this call</Say>
</Gather>
<Hangup/>
</Response>
Finally, set the "Voice Request URL" on your Twilio number to the full publicly available URL for the "attempt_call.php" file you created.
For more details, all of this code above is also available with mode in-depth explanation on the Call Screening HowTo which is available on our website.