Death to SMS

email-to-sms.js

const from = '+1xxxxxxxxxx' // your phone number
const sender = 'address@domain.tld' // your email address

exports.handler = function (context, event, callback) {
  // use the first part of the reply-to address as destination
  const to = event.to.split('@').shift()
  
  // take only the first line of the email body as the sms message
  const body = event.text.split('\n').shift()
  
  // display a log message for debugging
  console.log('to: [%s] message: %s', to, body)

  // parse message envelope
  const envelope = JSON.parse(event.envelope)
  
  // only accept emails from yourself
  if (envelope.from !== sender) {
    console.log('invlid sender: %s ', envelope.from)
    
    // quietly fail
    return callback()
  }

  // send sms using Twilio with quiet failure
  context.getTwilioClient().messages.create({ from, to, body }, () => callback())
}

sms-to-email.js

// import sendgrid library
const sendgrid = require('@sendgrid/client')

// target email address
const email = 'address@domain.tld'

// sms email domain
const domain = 'sms.domain.tld'

exports.handler = function (context, event, done) {
  // authenticate with token
  sendgrid.setApiKey(context.SENDGRID_API_KEY)

  // configure request object
  const request = {
    method: 'POST',
    url: '/v3/mail/send',
    body: {
      personalizations: [{
        to: [{ email }]
      }],
      from: {
        email: `${event.From}@${domain}`
      },
      subject: `RE: SMS: ${event.From}`,
      content: [{
        type: 'text/plain', value: event.Body
      }]
    }
  }
  
  sendgrid
    .request(request) // send the email
    .then(() => done(null, new Twilio.twiml.MessagingResponse())) // send TwiML output
    .catch(done) // quiet failure
}