CloudFront Functions redirect for React/SPA app under subdirectory.

CloudFrontRedirectForSPA.js

function handler(event) {
    var request = event.request;
    var uri = request.uri;
    
    // Check if SPA App 1 Direcotry 
    if (uri.startsWith('/my-app-1')) {
        request.uri = '/my-app-1/index.html';
    } 
    // Check whether the URI is missing a file name.
    else if(uri.endsWith('/')) {
        request.uri += 'index.html';
    } 
    // Check whether the URI is missing a file extension.
    else if (!uri.includes('.')) {
        request.uri += '/index.html';
    }

    return request;
}