url-persistence.js

// store application state and/or data in an applications' location hash
//
// inspired by: urlHosted   http://urlhosted.graphicore.de/about.html
//  depends on: jszip       https://github.com/Stuk/jszip

window.addEventListener('load', function() {
    console.log('starting up...');
    var zip = new JSZip();

    if (window.location.hash === '') {
        console.log('snapshot not found, generating base image...');
        zip.file('etc/license', 'http://unlicense.org/');
        zip.file('etc/motd', "Hello World\n\nWelcome to url-persistence\n");
        
        window.location.hash = zip.generate({ type: 'base64' });
        console.log('refresh the page to restore the current snapshot');

    } else {
        console.log('restoring snapshot...');
        zip.load(window.location.hash.replace(/^#/, ''), { base64: true });
        
        // cat /etc/motd
        console.log(zip.file('etc/motd').asText());
    }
});