154 lines
4.4 KiB
JavaScript
154 lines
4.4 KiB
JavaScript
/*
|
|
MIT License http://www.opensource.org/licenses/mit-license.php
|
|
*/
|
|
|
|
"use strict";
|
|
|
|
const memoize = require("../util/memoize");
|
|
|
|
const LAZY_TARGET = Symbol("lazy serialization target");
|
|
const LAZY_SERIALIZED_VALUE = Symbol("lazy serialization data");
|
|
|
|
/**
|
|
* @template DeserializedType
|
|
* @template SerializedType
|
|
*/
|
|
class SerializerMiddleware {
|
|
/* istanbul ignore next */
|
|
/**
|
|
* @abstract
|
|
* @param {DeserializedType} data data
|
|
* @param {object} context context object
|
|
* @returns {SerializedType|Promise<SerializedType>} serialized data
|
|
*/
|
|
serialize(data, context) {
|
|
const AbstractMethodError = require("../AbstractMethodError");
|
|
throw new AbstractMethodError();
|
|
}
|
|
|
|
/* istanbul ignore next */
|
|
/**
|
|
* @abstract
|
|
* @param {SerializedType} data data
|
|
* @param {object} context context object
|
|
* @returns {DeserializedType|Promise<DeserializedType>} deserialized data
|
|
*/
|
|
deserialize(data, context) {
|
|
const AbstractMethodError = require("../AbstractMethodError");
|
|
throw new AbstractMethodError();
|
|
}
|
|
|
|
/**
|
|
* @param {any | function(): Promise<any> | any} value contained value or function to value
|
|
* @param {SerializerMiddleware<any, any>} target target middleware
|
|
* @param {object=} options lazy options
|
|
* @param {any=} serializedValue serialized value
|
|
* @returns {function(): Promise<any> | any} lazy function
|
|
*/
|
|
static createLazy(value, target, options = {}, serializedValue) {
|
|
if (SerializerMiddleware.isLazy(value, target)) return value;
|
|
const fn = typeof value === "function" ? value : () => value;
|
|
fn[LAZY_TARGET] = target;
|
|
/** @type {any} */ (fn).options = options;
|
|
fn[LAZY_SERIALIZED_VALUE] = serializedValue;
|
|
return fn;
|
|
}
|
|
|
|
/**
|
|
* @param {function(): Promise<any> | any} fn lazy function
|
|
* @param {SerializerMiddleware<any, any>=} target target middleware
|
|
* @returns {boolean} true, when fn is a lazy function (optionally of that target)
|
|
*/
|
|
static isLazy(fn, target) {
|
|
if (typeof fn !== "function") return false;
|
|
const t = fn[LAZY_TARGET];
|
|
return target ? t === target : !!t;
|
|
}
|
|
|
|
/**
|
|
* @param {function(): Promise<any> | any} fn lazy function
|
|
* @returns {object} options
|
|
*/
|
|
static getLazyOptions(fn) {
|
|
if (typeof fn !== "function") return undefined;
|
|
return /** @type {any} */ (fn).options;
|
|
}
|
|
|
|
/**
|
|
* @param {function(): Promise<any> | any} fn lazy function
|
|
* @returns {any} serialized value
|
|
*/
|
|
static getLazySerializedValue(fn) {
|
|
if (typeof fn !== "function") return undefined;
|
|
return fn[LAZY_SERIALIZED_VALUE];
|
|
}
|
|
|
|
/**
|
|
* @param {function(): Promise<any> | any} fn lazy function
|
|
* @param {any} value serialized value
|
|
* @returns {void}
|
|
*/
|
|
static setLazySerializedValue(fn, value) {
|
|
fn[LAZY_SERIALIZED_VALUE] = value;
|
|
}
|
|
|
|
/**
|
|
* @param {function(): Promise<any> | any} lazy lazy function
|
|
* @param {function(any): Promise<any> | any} serialize serialize function
|
|
* @returns {function(): Promise<any> | any} new lazy
|
|
*/
|
|
static serializeLazy(lazy, serialize) {
|
|
const fn = memoize(() => {
|
|
const r = lazy();
|
|
if (r && typeof r.then === "function") {
|
|
return r.then(data => data && serialize(data));
|
|
}
|
|
return serialize(r);
|
|
});
|
|
fn[LAZY_TARGET] = lazy[LAZY_TARGET];
|
|
/** @type {any} */ (fn).options = /** @type {any} */ (lazy).options;
|
|
lazy[LAZY_SERIALIZED_VALUE] = fn;
|
|
return fn;
|
|
}
|
|
|
|
/**
|
|
* @param {function(): Promise<any> | any} lazy lazy function
|
|
* @param {function(any): Promise<any> | any} deserialize deserialize function
|
|
* @returns {function(): Promise<any> | any} new lazy
|
|
*/
|
|
static deserializeLazy(lazy, deserialize) {
|
|
const fn = memoize(() => {
|
|
const r = lazy();
|
|
if (r && typeof r.then === "function") {
|
|
return r.then(data => deserialize(data));
|
|
}
|
|
return deserialize(r);
|
|
});
|
|
fn[LAZY_TARGET] = lazy[LAZY_TARGET];
|
|
/** @type {any} */ (fn).options = /** @type {any} */ (lazy).options;
|
|
fn[LAZY_SERIALIZED_VALUE] = lazy;
|
|
return fn;
|
|
}
|
|
|
|
/**
|
|
* @param {function(): Promise<any> | any} lazy lazy function
|
|
* @returns {function(): Promise<any> | any} new lazy
|
|
*/
|
|
static unMemoizeLazy(lazy) {
|
|
if (!SerializerMiddleware.isLazy(lazy)) return lazy;
|
|
const fn = () => {
|
|
throw new Error(
|
|
"A lazy value that has been unmemorized can't be called again"
|
|
);
|
|
};
|
|
fn[LAZY_SERIALIZED_VALUE] = SerializerMiddleware.unMemoizeLazy(
|
|
lazy[LAZY_SERIALIZED_VALUE]
|
|
);
|
|
fn[LAZY_TARGET] = lazy[LAZY_TARGET];
|
|
fn.options = /** @type {any} */ (lazy).options;
|
|
return fn;
|
|
}
|
|
}
|
|
|
|
module.exports = SerializerMiddleware;
|