Can a TwiML bin use both Voice & SMS features?

Question

Using only a single TwiML bin, is it possible to mix voice and SMS verbs? I get errors when I try.

For example, a call comes into a Twilio number, TwiML would first send an SMS <Message to="+18005551212"> {{From}}: <Body>Hello World!</Body> </Message> then forward the call <Dial>+18005551212</Dial>. Another example: use mixed Voice/SMS to send an SMS for handling when Dial doesn't connect.

If it's not possible currently, is there a technical reason why TwiML voice & TwiML SMS couldn't be further developed to be interoperable?

philnash philnash · Accepted Answer · 2018-05-24T03:24:22

Twilio developer evangelist here.

Wanted to follow up with the other comments here. If you are just using a TwiML Bin to respond to an incoming call and you want to send SMS messages then the <Sms> verb is what you want.

However, it is deprecated. <Sms> is also not as up to date as the <Message> verb in messaging TwiML. It can't send messages over 160 characters or media messages or use messaging services.

The recommendation is to move on from a TwiML Bin and send the message using the REST API while returning TwiML to control the call. You could do this with a Twilio Function so you still wouldn't need to host anything. Here's a quick example:

exports.handler = function(context, event, callback) {
    const twilioClient = context.getTwilioClient();

    twilioClient.messages.create({
        to: TO_NUMBER,
        from: FROM_NUMBER
        body: "Hello world"
    }).then(function() {
        const twiml = new Twilio.twiml.VoiceResponse();
        twiml.dial(TO_NUMBER);

        callback(null, twiml);
    });
}

Let me know if that helps at all.

Can a TwiML bin use both Voice & SMS features?

1 Answers