How to validate the time span in a rail model?

Question

Ruby on Rails

There is a simple rails application, there is a user model User, the user has a date_of_birth field
How to validate this field in the model to check that date_of_birth is in the range from 01/01/1900 to today, inclusive, despite the fact that this field may not be at all, but if there is, then it fits this range.

Answer 1

class User < ApplicationRecord
  validates_with UserBirthZalupaValidator
end

class UserBirthZalupaValidator < ActiveModel::Validator
  def validate(record)
    begin
      birth = Date.parse(record.birth_date.to_s)
      record.errors.add(:base, "zlpa") unless birth.between?(start_date, end_date)
    rescue StandardError => e
      Rails.logger.error("Full zlpa: #{e.inspect}")
    end
  end

  def start_date
    Date.new(1900,1,1)
  end

  def end_date
    Time.zone.today
  end
end

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