localstorage_with_expiration.js

/**
 * Stores a value in the localStorage with an optional expiration time.
 *
 * @param {string} key - The key to associate with the stored value.
 * @param {*} value - The value to be stored.
 * @param {number} expiration - The duration in milliseconds for which the item should be stored before it expires.
 */
function setItemWithExpiration(key, value, expiration) {
    const item = {
      value: value,
      expiration: expiration ? new Date().getTime() + expiration : null
    };
    localStorage.setItem(key, JSON.stringify(item));
}


// setItemWithExpiration('example', 'abcd', 60 * 60 * 1000) // 1hr
  
  /**
   * Retrieves a value from the localStorage based on the provided key. It also checks if the stored item has expired and removes it if necessary.
   *
   * @param {string} key - The key associated with the stored value.
   * @returns {*} - The stored value if it exists and has not expired, otherwise returns null.
   */
  function getItemWithExpiration(key) {
    const item = JSON.parse(localStorage.getItem(key));
    if (item && item.expiration && new Date().getTime() > item.expiration) {
      localStorage.removeItem(key);
      return null;
    }
    return item ? item.value : null;
  }