mqsigned.js

'use strict';

const v4 = require('aws-signature-v4');
const crypto = require('crypto');

exports.handler = (event, context, callback) => {
  const url = v4.createPresignedURL(
    'GET',
    process.env.IOT_ENDPOINT_HOST.toLowerCase(),
    '/mqtt',
    'iotdevicegateway',
    crypto.createHash('sha256').update('', 'utf8').digest('hex'),
    {
      'key': process.env.IOT_ACCESS_KEY,
      'secret': process.env.IOT_SECRET_KEY,
      'protocol': 'wss',
      'region': process.env.IOT_AWS_REGION,
    }
  );

  const response = {
    statusCode: 200,
    headers: {
      'Access-Control-Allow-Origin': '*',
      'Access-Control-Allow-Credentials' : true
    },
    body: JSON.stringify({ url: url }),
  };

  callback(null, response);
}