gsh | engine framework developed based on the redis network layer

const isEmpty = val => val == null || !(Object.keys(val) || val).length;


isEmpty([]); // true
isEmpty({}); // true
isEmpty(''); // true
isEmpty([1, 2]); // false
isEmpty({ a: 1, b: 2 }); // false
isEmpty('text'); // false
isEmpty(123); // true -  

const geometricProgression = (end, start = 1, step = 2) =>
  Array.from({
    length: Math.floor(Math.log(end / start) / Math.log(step)) + 1,
  }).map((_, i) => start * step ** i);


geometricProgression(256); // [1, 2, 4, 8, 16, 32, 64, 128, 2  

public void update(Book book) throws BookNotFoundException, VersionMismatchException {
    if (!collection.containsKey(book.getId())) {
      throw new BookNotFoundException("Not found book with id: " + book.getId());
    }

    var latestBook = coll  

public void bookRoom(int roomNumber) throws Exception {

    var room = hotelDao.getById(roomNumber);

    if (room.isEmpty()) {
      throw new Exception("Room number: " + roomNumber + " does not exist");
    } else {
      if (room.get().isBooked()  

@Override
  public Book getBook(String title) {
    Book bookDTo;
    try (var session = sessionFactory.openSession()) {
      var sqlQuery = session.createSQLQuery("SELECT b.title as \"title\","
          + " b.price as \"price\"" + " FROM Book b wh