Save the info from the token into another table

Question

I have a model Aulas wich has a tokenfield for the model Courses. When I save the Aula, I want to extract the name of the Course in the token and save into the name of the Aula, is that possible? So instead of "aula.course.name" I can have the same name on "aula.name"

Models

class Aula < ActiveRecord::Base
  attr_accessible :name,:course_tokens

  has_many :menagements
   has_many :courses, :through => :menagements

  attr_reader :course_tokens

  def course_tokens=(tokens)
  self.course_ids = Course.ids_from_tokens(tokens)
  end
end

class Course < ActiveRecord::Base
  attr_accessible :aula_id, :name
  has_many :menagements
  has_many :aulas, :through => :menagements

  def self.tokens(query)
    courses = where("name like ?", "%#{query}%")
    if courses.empty?
      [{id: "<<<#{query}>>>", name: "New: \"#{query}\""}]
    else
      courses
    end
  end

  def self.ids_from_tokens(tokens)
    tokens.gsub!(/<<<(.+?)>>>/) { create!(name: $1).id }
    tokens.split(',')
  end
end

And the controler

  def create
    @aula = Aula.new(params[:aula])

    respond_to do |format|
      if @aula.save
        format.html { redirect_to @aula, notice: 'Aula was successfully created.' }
        format.json { render json: @aula, status: :created, location: @aula }
      else
        format.html { render action: "new" }
        format.json { render json: @aula.errors, status: :unprocessable_entity }
      end
    end
  end

I tried:

def do_something_before_save
 self.name = self.courses.each do 
end

and i get

--- - !ruby/object:Course attributes: id: 1 name: Extra 2B aula_id: 11 created_at: 2013-03-08 13:26:15.806995000 Z updated_at: 2013-03-14 19:58:53.542650000 Z 

but I try this, and it shows the same result

def do_something_before_save
 self.name = self.courses.each do |course|
   course.name
end

The info is there, I just don´t seem to get it. The part I want is Extra 2B

Answer 1

You can add a before_save callback which will trigger a method before saving Aula class.

Something like:

class Aula < ActiveRecord::Base
  ...

  before_save :do_something_before_save

  def do_something_before_save
    self.name = self.course.name
  end
  ...
end

Answer 2

I fugured that because it is an Array, I should specify the one course I want to show the info, so I did

  def do_something_before_save
   self.name = self.courses.first.name
  end

first is to specify the one course I want the info.

Thanks for the help.