/** * localStorage utils */ const lastUpdatedSuffix = '__lastUpdated'; export default { set(key, value) { try { localStorage.setItem(key, JSON.stringify(value)); return true; } catch (err) { return false; } }, get(key) { const value = localStorage.getItem(key); try { return JSON.parse(value); } catch (err) { return value; } }, remove(key) { try { localStorage.removeItem(key); return true; } catch (err) { return false; } }, // Watch changes to a specified key - returns value on change watch(key, callback) { window.addEventListener('storage', event => { if (event.key === key) callback(this.get(key)); }); }, // set() with an additional key containing the current time + expiration time setWithExpireTime(key, value, maxAge) { const lastUpdatedKey = key + lastUpdatedSuffix; const lastUpdatedTime = Date.now() + maxAge; this.set(key, value) && this.set(lastUpdatedKey, lastUpdatedTime); }, // Whether the value of a key set with setWithExpireTime() has expired hasExpired(key) { const lastUpdatedKey = key + lastUpdatedSuffix; const lastUpdatedTime = this.get(lastUpdatedKey); if (Date.now() > lastUpdatedTime) { return true; } return false; }, };