Shared cache with TTL, background refresh and tab sync
// ==UserScript==
// @name Smart Shared Cache System
// @namespace smart.cache.shared
// @version 2.0
// @description Shared cache with TTL, background refresh and tab sync
// @match *://*/*
// @grant GM_setValue
// @grant GM_getValue
// @grant GM_deleteValue
// @grant GM_listValues
// @run-at document-start
// @license MIT
// ==/UserScript==
(function () {
'use strict';
const PREFIX = "GLOBAL_CACHE_";
const channel = new BroadcastChannel("GLOBAL_CACHE_SYNC");
const Cache = {
// 📦 set with TTL
set(key, value, ttl = 300) {
const data = {
value,
expiry: Date.now() + ttl * 1000
};
GM_setValue(PREFIX + key, JSON.stringify(data));
// уведомляем другие вкладки
channel.postMessage({ type: "update", key });
},
// 📥 get with auto cleanup
get(key) {
const raw = GM_getValue(PREFIX + key, null);
if (!raw) return null;
try {
const data = JSON.parse(raw);
if (Date.now() > data.expiry) {
GM_deleteValue(PREFIX + key);
return null;
}
return data.value;
} catch {
GM_deleteValue(PREFIX + key);
return null;
}
},
// 🔄 get with background refresh
async getOrRefresh(key, ttl, fetchFunction) {
const existing = this.get(key);
if (existing) return existing;
// если нет — загружаем в фоне
const fresh = await fetchFunction();
this.set(key, fresh, ttl);
return fresh;
},
// 🗑 удалить
delete(key) {
GM_deleteValue(PREFIX + key);
channel.postMessage({ type: "delete", key });
},
// 🧹 очистить всё
clearAll() {
GM_listValues().forEach(k => {
if (k.startsWith(PREFIX)) {
GM_deleteValue(k);
}
});
channel.postMessage({ type: "clear" });
}
};
// 🔔 Синхронизация вкладок
channel.onmessage = (event) => {
const msg = event.data;
if (!msg) return;
if (msg.type === "update") {
console.log("Cache updated in another tab:", msg.key);
}
if (msg.type === "delete") {
console.log("Cache deleted in another tab:", msg.key);
}
if (msg.type === "clear") {
console.log("Cache cleared in another tab");
}
};
// ====== Пример использования ======
async function example() {
const data = await Cache.getOrRefresh(
"apiData",
600,
async () => {
console.log("Fetching fresh data...");
const response = await fetch("https://api.example.com/data");
return await response.json();
}
);
console.log("Data:", data);
}
// example(); // раскомментируй при необходимости
})();