var CryptoJS = require("crypto-js");

var SECRET_KEY = 'my secret key';

var secureStorage = new SecureStorage(localStorage, {
    hash: function hash(key) {
        key = CryptoJS.SHA256(key, SECRET_KEY);

        return key.toString();
    },
    encrypt: function encrypt(data) {
        data = CryptoJS.AES.encrypt(data, SECRET_KEY);

        data = data.toString();

        return data;
    },
    decrypt: function decrypt(data) {
        data = CryptoJS.AES.decrypt(data, SECRET_KEY);

        data = data.toString(CryptoJS.enc.Utf8);

        return data;
    }
});

var data = {
    secret: 'data'
};

// there is no need to stringify/parse you objects before and after storing.

secureStorage.setItem('data', data);
// stores in localStorage like:
// key => value
// "ad36d572..." => "w1svi6n..."

var decryptedData = secureStorage.getItem('data');
// returns { secret: 'data' }

secureStorage.removeItem('data');
// removes the entry 'data'

secureStorage.key(id)
// returns the hashed version of the key you passed into setItem with the given id.

secureStorage.clear();
// clears all data in the underlining sessionStorage/localStorage.

secureStorage.length;
// the number of entries in the underlining sessionStorage/localStorage.