Implementing IndexedDB

1 - Open conection to the DB.js

const memokingDB = (function() {
    var mkDB = {};
    var datastore = null;

    /** Open conection to the DB **/
    mkDB.open = function(callback) {
        var request = indexedDB.open("memoking");

        request.onupgradeneeded = function() {
            // The database did not previously exist, so create object stores and indexes.
            var db = request.result;
            var store = db.createObjectStore('stats', {keyPath: 'timestamp'});
            var gameIndex = store.createIndex("by_game", "game");
            var scoreIndex = store.createIndex("by_score", "score");

            // Populate with initial TEST data.
            store.put({game: "Cards", score: 100, timestamp: 1});
        };

        request.onsuccess = function() {
            datastore = request.result;
            callback();
        };

        // Error handling
        request.onerror = mkDB.onerror;
    };
    
    /*
    *
    *  Place for other funcions working with DB
    *
    */
   
    return mkDB;
}());

export default memokingDB;