Question

consider scenario,

User model with name, birth_date fields (here birth_date is optional)

inside view form birth_date is assigned as ’31/31/1985′ which is invalid

ideally user object should be invalid and raise and error on birth_date field but thats not happening and user object gets saved with birth_date as blank which is completely misleading.

After debugging found that while assigning attributes birth_date value it gets assigned as blank and as birth_date is optional object gets saved.

u = User.new
# invalid date assignment
u.birth_date = '31/31/2011'
u.birth_date #=> nil
# valid date assignment
u.birth_date = '1/1/2011'
u.birth_date #=> Sat, 01 Jan 2011

class User < ActiveRecord::Base
  def initialize(args={})
    logger.info args[:birth_date] #invalid value comes upto here but vanishes afterwords
    super
  end
end

I am not saying its incorrect, but it should not misleading from user point of view.
bcz after entering invalid birth_date user will assume he entered correct birth_date but actually his birth_date is not saved at all.

Any clue how to get around this issue ??

Answer 1

I don’t know whether the allow_blank and allow_nil options work with custom validations, but it’s easy to write it yourself.

validate :valid_birth_date

private
  def valid_birth_date
    errors.add(:birth_date, "is invalid.") unless birth_date.blank? || valid_date?(birth_date)
  end

  def valid_date?(date)
    begin
      !!Date.parse(date)
    rescue
      false
    end
  end