A Map extended as a Cache. Optional KeyExtractor - Function, optional ValueTransformer - Functions, as well as an optional validityPeriod after which an entry is automatically going to be removed.
This script should not be not be installed directly. It is a library for other scripts to include with the meta directive // @require https://update.greasyfork.org/scripts/405143/815223/SimpleCache.js
// ==UserScript==
// @name SimpleCache
// @namespace hoehleg.userscripts.private
// @version 0.1
// @description A Map extended as a Cache. Optional KeyExtractor - Function, optional ValueTransformer - Functions, as well as an optional validityPeriod after which an entry is automatically going to be removed.
// @author Gerrit Höhle
//
// @grant none
//
// @require https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js
// ==/UserScript==
/* jshint esnext: true */
/* globals $, jQuery */
const SimpleCache = (() => {
const cloneObject = (obj) => {
if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) {
return obj;
}
return jQuery.extend(true, {}, obj);
};
return class SimpleCache extends Map {
constructor({ keyExtractor = k => k, setValueTransformer = v => cloneObject(v), getValueTransformer = v => cloneObject(v) } = {}) {
super();
Object.assign(this, { keyExtractor, setValueTransformer, getValueTransformer });
}
get(key) {
const finalKey = this.keyExtractor(key);
return this.getValueTransformer(super.get(finalKey));
}
set(key, value, validityPeriodMs = 0) {
const finalKey = this.keyExtractor(key);
super.set(finalKey, this.setValueTransformer(value));
if (validityPeriodMs > 0) {
setTimeout(() => this.delete(finalKey), validityPeriodMs);
}
return this;
}
has(key) {
return super.has(this.keyExtractor(key));
}
delete(key) {
return super.delete(this.keyExtractor(key));
}
};
})();