getting callback function error in twilio functions

Question

My debugger keeps on sending me a callback error (see img link below) for this function. I also would like to continue from my function back to studio, the studio docs say I need "A successful return (HTTP 20X)" what am I missing

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

const client = require('twilio')();
const msg = event.Msg;
client.messages
  .create({
     body: msg,
     from: '+17322222222',
     to: '+13477777777'
   })
  .then(message => console.log(message.sid));
};

Error msg from Debugger

if I insert callback() at end of code, I get a successful return but the message doesn't get sent then.

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

const client = require('twilio')();
const msg = event.Msg;

client.messages
  .create({
     body: msg,
     from: '+17322222222',
     to: '+13477777777'
   });

  callback();
};

Answer 1

You need to have the callback execute after the message is successfully sent.

This can be done using promises or async/await syntax as shown below:

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

   let twilioClient = context.getTwilioClient();

   twilioClient.messages
     .create({
       body: 'Hello World',
       to: '+13477777777',
       from: '+17322222222',
     }).then(message =>  {
       console.log(message.sid);
       callback(null, {result: "success"});
     })
    .catch(error => {
       console.log(error);
       callback({result: "error"});
    });
};

or

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

    let twilioClient = context.getTwilioClient();

    let sendSMS = () => { 
        try {   
        let result = twilioClient.messages
        .create({
           body: 'Hello World',
           to: '+13477777777',
           from: '+17322222222',
         });
         return result;
        } catch(e) {
          console.log(e);
          callback(e);
        }
    };

    let result = await sendSMS();
    callback(null, result);
};