Optimizing request URI for CloudFront with Lambda@Edge that has HUGO site as origin.

lambda_edge_hugo.js

'use strict';
exports.handler = (event, context, callback) => {
    const host = '<REPLARE_TO_YOUR_HOST>'; // e.g. https://michimani.net

    // Extract the request from the CloudFront event that is sent to Lambda@Edge
    var request = event.Records[0].cf.request;

    // Extract the URI from the request
    var requestUri = request.uri;

    // Do not anything when requesting to top page
    if (requestUri == '' || requestUri == '/') {
        callback(null, request);
    }

    // Redirect to URI end with '/' if URL end with 'index.html' or not '/'
    if (requestUri.match(/((page|post|posts|tags|categories|archives|about)(\/.*[^\/])?|\/index\.html)$/)) {
        const redirectUrl = host + requestUri.replace('/index.html', '') + '/';
        const response = {
            status: '301',
            statusDescription: 'Found',
            headers: {
                location: [{
                    key: 'Location',
                    value: redirectUrl,
                }],
          },
        }
        // return response to redirect (for viewer)
        callback(null, response);
    };

    // Match any '/' that occurs at the end of a URI. Replace it with a default index
    const actualUri = requestUri.replace(/\/$/, '\/index.html');

    console.log('request URI: ' + requestUri);
    console.log('actual URI: ' + actualUri);

    // Replace the received URI with the URI that includes the index page
    request.uri = actualUri;

    // Return to CloudFront (for origin)
    callback(null, request);
};