Twilio functions: Sending WhatsApp message when incoming call is received

Question

I want to use the Twilio functions to run my actions when a phone call is received.

Simple task: When i receive a phone call on the twilio number, i want to forward the phone call and also send a message to a whatsapp number to inform about the incoming phone call.

There is a similar example on the Twilio website: https://support.twilio.com/hc/en-us/articles/360017437774-Combining-Voice-SMS-and-Fax-TwiML-in-the-Same-Response

But i couldn't get this to work with WhatsApp. It only works with SMS Messages, but when i replace the to and from params with the whatsapp:+01234567890 numbers, i did not receive any messages.

Answer 1

I'm posting one way of doing it, tested with my Twilio WhatsApp sandbox, it works.

/**
 *  This Function will forward a call to another phone number.
 *  It will send a WhatsApp message before doing that. 
 */

exports.handler = function (context, event, callback) {

    let fromNumber = event.From; // number which called our Twilio number  
    let recipientNumber = '+10000000001'; // number where the call will be forwarded

    let client = context.getTwilioClient();

    client.messages
        .create({
            from: 'whatsapp:+10000000002', // Twilio's WhatsApp sandbox number
            body: `Call from ${fromNumber}, forwarded to ${recipientNumber}.`,
            to: 'whatsapp:+10000000003' // WhatsApp number registered with sandbox
        })
        .then(function (message) {
            console.log(message.sid);
            forwardCall();
        });

    function forwardCall() {
        // generate the TwiML to tell Twilio how to forward this call
        let twiml = new Twilio.twiml.VoiceResponse();
        let dialParams = {};
        twiml.dial(dialParams, recipientNumber);
        // return the TwiML
        callback(null, twiml);
    }

};