Serverless Country Lookup with AWS (Lambda+CloudFront)

LambdaFucntion.js

"use strict";

// countryLookup solves the Cloudfront website use-case

/*
  Typical Cloudfront event structure to consume:
  {
    "Records": [
      {
        "cf": {
          "request": {
            "uri": "/test",
            "headers": {
              "cloudfront-viewer-country": [
                {
                  key: "Cloudfromt-Viewer-Country",
                  value: "FR"
                }
              ]
            }
          }
        }
      }
    ]
  }
*/

 exports.handler = (event, context, callback) => {
  //console.log('EVENT', event);
  //console.log('CONTEXT', context);   
  const request = event.Records[0].cf.request;
  const headers = request.headers;
  const countryCode = headers["cloudfront-viewer-country"][0].value;

  const response = {
    status: "200",
    headers: {
      ["cache-control"]: [
        {
          key: "Cache-Control",
          value: "no-cache, no-store, private"
        }
      ]
    },
    body: JSON.stringify({
      countryCode
    })
  };

  callback(null, response);

};