sql - Rails code readability for my validation -

the code works fine in detecting overlapping dates not save booking if exist given room. however, had twist code make work because validation make update in controller not valid instead of save. want know wrong code not valid should apply save , not update.

in fact, tell me booking cannot saved instead of throwing error, did not update booking.end_date in contoller while should raise error when save , not when try update it:

i have controller create new booking room (this want improve):

  def create_book_now     @room = room.find(params[:room_id])     booking = @room.bookings.build(booking_params)      if booking.save  #i want not save if model validation not ok       if @room.bookings.last.update(end_date: booking.start_date + booking.length.days) # have check if true validation work, sure not normal         flash[:notice] = "booking done"         redirect_to root_path       else         flash[:error] =  "booking.errors.full_messages.first if booking.errors.any?"         redirect_to room_book_now_path(@room.id)       end     else       flash[:error] =  booking.errors.full_messages.first if booking.errors.any?       redirect_to room_book_now_path(@room.id)     end   end 

the new booking go through validation make sure no booking overlapping date has been made:

class booking < activerecord::base     belongs_to :room      validates :length, :presence => true      validate :dates_are_available      def dates_are_available         room = room.find(self.room_id)         # if room.find(self.room_id).bookings.exists?         #    self.errors.add(:base, 'date taken')         # end         conditions = []         conditions << '(start_date >= :new_start_date , end_date >= :new_end_date)'         conditions << '(start_date >= :new_start_date , end_date <= :new_end_date)'         conditions << '(end_date between :new_start_date , :new_end_date)'         conditions << '(start_date <= :new_start_date , end_date >= :new_end_date)'         if room.bookings.where(conditions.join(' or '), new_start_date: self.start_date, new_end_date: self.end_date).exists?             self.errors.add(:base, 'date taken')             return false         end     end end 

so question how make code in controller better validation work when booking saved , not when updated

you can that, check bookings assing room before save, , 1 one check condition.

def dates_are_available     room.bookings.each |b|         if bookings.start_date             self.errors.add(:base, 'date taken')         end     end end