LocalStorage/SessionStorage Polyfill with Safari Private Browsing support.

storagePolyfill.js

// Refer to https://gist.github.com/remy/350433
try {
    // Test webstorage existence.
    if (!window.localStorage || !window.sessionStorage) throw "exception";
    // Test webstorage accessibility - Needed for Safari private browsing.
    localStorage.setItem('storage_test', 1);
    localStorage.removeItem('storage_test');
} catch(e) {
    (function () {
        var Storage = function (type) {
            function createCookie(name, value, days) {
                var date, expires;

                if (days) {
                    date = new Date();
                    date.setTime(date.getTime()+(days*24*60*60*1000));
                    expires = "; expires="+date.toGMTString();
                } else {
                    expires = "";
                }
                document.cookie = name+"="+value+expires+"; path=/";
            }

            function readCookie(name) {
                var nameEQ = name + "=",
                    ca = document.cookie.split(';'),
                    i, c;

                for (i=0; i < ca.length; i++) {
                    c = ca[i];
                    while (c.charAt(0)==' ') {
                        c = c.substring(1,c.length); 2480
                    }

                    if (c.indexOf(nameEQ) == 0) {
                        return c.substring(nameEQ.length,c.length);
                    }
                }
                return null;
            }

            function setData(data) {
                // Convert data into JSON and encode to accommodate for special characters.
                data = encodeURIComponent(JSON.stringify(data));
                // Create cookie.
                if (type == 'session') {
                    createCookie(getSessionName(), data, 365);
                } else {
                    createCookie('localStorage', data, 365);
                }
            }

            function clearData() {
                if (type == 'session') {
                    createCookie(getSessionName(), '', 365);
                } else {
                    createCookie('localStorage', '', 365);
                }
            }

            function getData() {
                // Get cookie data.
                var data = type == 'session' ? readCookie(getSessionName()) : readCookie('localStorage');
                // If we have some data decode, parse and return it.
                return data ? JSON.parse(decodeURIComponent(data)) : {};
            }

            function getSessionName() {
                // If there is no name for this window, set one.
                // To ensure it's unquie use the current timestamp.
                if(!window.name) {
                    window.name = new Date().getTime();
                }
                return 'sessionStorage' + window.name;
            }

            // Initialise if there's already data.
            var data = getData();

            return {
                length: 0,
                clear: function () {
                    data = {};
                    this.length = 0;
                    clearData();
                },
                getItem: function (key) {
                    return data[key] === undefined ? null : data[key];
                },
                key: function (i) {
                    // not perfect, but works
                    var ctr = 0;
                    for (var k in data) {
                        if (ctr == i) return k;
                        else ctr++;
                    }
                    return null;
                },
                removeItem: function (key) {
                    delete data[key];
                    this.length--;
                    setData(data);
                },
                setItem: function (key, value) {
                    data[key] = value+''; // forces the value to a string
                    this.length++;
                    setData(data);
                }
            };
        };

        // Replace window.localStorage and window.sessionStorage with out custom
        // implementation.
        var localStorage = new Storage('local');
        var sessionStorage = new Storage('session');
        window.localStorage = localStorage;
        window.sessionStorage = sessionStorage;
        // For Safari private browsing need to also set the proto value.
        window.localStorage.__proto__ = localStorage;
        window.sessionStorage.__proto__ = sessionStorage;
    })();
}

Works like a charm for me, we only have to remove the typo @bigotilda noticed !

Nice! This method is working correctly in Safari Private Mode. Thanks

you rock!,..... you're the man! Thanks.

I created a working one based on this.

Just what I was looking for.

The method really works. I was just looking for something like this. I have never worked with the Safari browser at all and I recently had to get acquainted with it. I also read about private browsing safari, a friend sent me some informative information https://moonlock.com/private-browsing-safari and by the way, now I only use safari! It's really very minimalistic and comfortable. It also turns out to be well protected.

Immerse yourself in the challenging journey of Drift Boss, where you will drive through sharp turns and dangerous slopes.