serverless-offline-msk/examples/docker-compose-single-broker/node_modules/p-memoize/index.js

A serverless offline plugin that enables AWS MSK events

'use strict';
const mimicFn = require('mimic-fn');
const mapAgeCleaner = require('map-age-cleaner');
const pSettle = require('p-settle');

const cacheStore = new WeakMap();

const pMemoize = (fn, {cachePromiseRejection = false, ...options} = {}) => {
	const {maxAge, cacheKey} = options;
	const cache = options.cache || new Map();

	if (Number.isSafeInteger(maxAge)) {
		mapAgeCleaner(cache);
	} else if (typeof maxAge !== 'undefined') {
		throw new TypeError('maxAge is not a safe integer.');
	}

	const memoized = async function (...arguments_) {
		const key = cacheKey ? cacheKey(arguments_) : arguments_[0];

		const cacheItem = cache.get(key);
		if (cacheItem) {
			return cacheItem.data;
		}

		const promise = fn.apply(this, arguments_);
		cache.set(key, {
			data: promise,
			// Ref. https://github.com/sindresorhus/p-memoize/issues/39#issuecomment-985301556
			maxAge: (2 ** 31) - 1
		});

		const [{reason}] = await pSettle([promise]);
		if (!cachePromiseRejection && reason) {
			cache.delete(key);
		} else if (maxAge) {
			// Promise fulfilled, so start the timer
			cache.set(key, {
				data: promise,
				maxAge: Date.now() + maxAge
			});
		}

		return promise;
	};

	mimicFn(memoized, fn);
	cacheStore.set(memoized, cache);

	return memoized;
};

module.exports = pMemoize;

module.exports.clear = memoized => {
	if (!cacheStore.has(memoized)) {
		throw new Error('Can\'t clear a function that was not memoized!');
	}

	const cache = cacheStore.get(memoized);

	if (typeof cache.clear !== 'function') {
		throw new TypeError('The cache Map can\'t be cleared!');
	}

	cache.clear();
};