Handler for Lambda function

Handler.js

exports.handler = (event, context, callback) => {
  const { request, config } = event.Records[0].cf;

  let originalUri = request.uri;
  const parsedPath = path.parse(originalUri);

  if (parsedPath.ext === '') {
    request.uri = '/index.html';

    let metaUrl = 'https://houseofradon.com';

    if (parsedPath.dir === '/') {
      metaUrl += '/api/meta?type=' + parsedPath.base;
    } else if (parsedPath.dir === '/creative' || parsedPath.dir === '/venture') {
      metaUrl += '/api/case/' + parsedPath.base + '/meta';
    } else if (parsedPath.dir === '/join-us') {
      metaUrl += '/api/career/' + parsedPath.base + '/meta';
    } else {
      metaUrl += '/api/meta?type=';
    }

    fetchMetaData(metaUrl, (isOk, metaTags, metaHeaders) => {
      if (!isOk) {
        return callback(null, request); // Return same request so CloudFront can process as usual.
      } else {
        const contentUrl = 'https://houseofradon.com/index.html';

        fetchIndexHtmlAndCreateCloudFrontResponse(contentUrl, metaTags, metaHeaders, (isOk, newResponse) => {
          if (!isOk) {
            return callback(null, request);
          } else {
            return callback(null, newResponse);
          }
        });
      }
    });
  } else {
    return callback(null, request);
  }
};