LambdaAtEdgeReverseProxy.js

'use strict';

module.exports.addCors = async (event, context, callback) => {
  const response = event.Records[0].cf.response;
  const headers = response.headers;
  
  response.statusCode = 200;

  headers['x-serverless-time'] = [{ key: 'x-serverless-time', value: Date.now().toString() }];
  headers['access-control-allow-origin'] = [{ key:'access-control-allow-origin', value: '*' }];
  
  delete headers['cache-control'];
  delete headers['location'];
  delete headers['expires'];
  delete headers['server'];

  return callback(null, response);
};