SimpleCache.js

var SimpleCache = function() {
    var _values = {};
    var getTime = function() {
        return Date.now() / 1000 | 0
    }
    this.get = function(key) {
        if (!(key in _values)) {
            return null
        }
        var vl = _values[key];
        if (!vl.time) {
            return vl.value
        } else if (vl.time < getTime()) {
            this.remove(key)
            return null;
        } else {
            return vl.value
        }
    }

    this.remove = function(key) {
        delete _values[key];
    };
    this.set = function(key, value, time) {
        _values[key] = {
            'time': time ? getTime() + time : 0,
            'value': value
        };
    };
    this.values = function() { return _values; };
}