Question

I am finding it hard to do some validation with my custom made validator.

Here it is:

class SomeValidator < ActiveModel::Validator
  def validate(record)
    if record.baggage > options[:max]
      record.errors[:baggage] << "is over #{options[:max]}."   
    end
  end
end

Now I am trying to send it this number which needs to be read from another model. This is my validated model:

class Seat < ActiveRecord::Base
  belongs_to :flight
  validates :baggage, :some => {:max => flight.max_allowance}
end

Where flight is the other model, and max_allowance is the number I want to read. This doesn’t work of course.

Any suggestions?

Answer 1

You can use a Proc as argument. Something like this:

validates :baggage, :some => {:max => Proc.new{|record| record.flight.max_allowance}}