$ npm install connect-diskdb

    var app = require('express')(),
        session = require('express-session'),
        SessionStore = require('connect-diskdb')(session);

    // create a DiskDB Session Store
    var options = {
        path: '', // path where the diskDB based file should be stored
        name: '', // name of the database
        db: '' // (optional) instead of passing 'path' and 'name' for the db, an existing diskDB instance can be passed.
    };
    var diskDBSessionStore = new SessionStore(options);    

    // enable sessions with diskDBSessionStore
    app.use(session({
        secret: 'MY_SECRET',
        store: diskDBSessionStore 
    }));

    // start the app
    app.listen(8080);