@publidata/utils-fontawesome/src/MemoryCache/index.js

Collection of methods to handle opening hours

/**
 * A simple in-memory cache
 * Inspired by: https://dev.to/seanwelshbrown/implement-a-simple-lru-cache-in-javascript-4o92
 * @class MemoryCache
 * @param {Number} capacity - the maximum number of items to store in the cache
 * @method get - get the value of a key
 * @method put - set a key value pair in the cache
 * @method reset - clear the cache
 */
class MemoryCache {
  constructor(_capacity) {
    this._cache = new Map();
    this.capacity = _capacity;
  }

  /**
   * Get the value of a key
   * @param {String} key
   * @returns {Object} whatever is stored in the cache
   */
  get(key) {
    let val = this._cache.get(key);
    return val;
  }

  /**
   * Set a key value pair in the cache
   * @param {String} key
   * @param {Object} value
   * @returns {void}
   * @throws {Error} if the key is not a string
   */
  put(key, value) {
    if (typeof key !== "string") throw new Error("Key must be a string");

    // Start by deleting the key if it already exists
    this._cache.delete(key);

    if (this._cache.size === this.capacity) {
      // Delete the first key in the cache with the oldest value
      this._cache.delete(this._cache.keys().next().value);
      this._cache.set(key, value);
    } else {
      this._cache.set(key, value);
    }
  }

  /**
   * Set multiple key value pairs in the cache
   * @param {Array<Object>} keyValues - an array of objects with key and value properties
   * @returns {void}
   * @throws {Error} if the key is not a string
   * @throws {Error} if the keyValues array is longer than the capacity of the cache
   */
  putAll(keyValues) {
    if (!Array.isArray(keyValues))
      throw new Error("keyValues must be an array");
    // In case the array is longer than the capacity
    if (keyValues.length > this.capacity)
      throw new Error("keyValues is longer than the capacity of the cache");

    keyValues.forEach((kv) => this.put(kv.key, kv.value));
  }

  /**
   * Clear the cache
   * @returns {void}
   */
  reset() {
    this._cache.clear();
  }
}

module.exports = MemoryCache;