service - inconsistent results from rails console v. dev UX -

upon creation of list of quantities, list attribute total_calories should updated sum of calories associated list. lists , foods associated has_many :through quantities, , each food has calories attribute.

when create list in rails development user interface hosted c9.io, behaves expected. when create list in console, not; total_calories not updated. how be?

i appreciate tips investigate, have never encountered issue of inconsistency between console , development user interface.

the service object count_calories.rb:

class countcalories    def initialize(list)     @list=list   end    def count     @calories = 0     @list.quantities.each |q|       @calories += food.find(q.food_id).calories     end     @list.update!(total_calories: @calories)     @list.save!   end  end 

the create method in list controller:

def create   @list = writelist.new(list_params).write   if @list.save     flash[:success] = "a list has been created!"     countcalories.new(@list).count     redirect_to @list   else     render 'new'   end end 

the service object write_list.rb, in case helpful:

class writelist    def initialize(params)     @params=params   end    def write     activerecord::base.transaction       list = list.new(days: @params[:days], name: @params[:name])       list.save!       3.times         food1 = food.all.sample.id         quantity.create!(food_id: food1, list_id: list[:id], amount: 1+rand(6))       end       list.save!       return list     end     rescue       return list.new(days: @params[:days], name: @params[:name])   end  end 

the thing can think of maybe has migration create total_calories:

class addtotalcaloriestolists < activerecord::migration   def change     add_column :lists, :total_calories, :integer, :default => 0   end end 

but mostly, baffled , appreciate tips.

i believe have on engineered problem. appears coming java web stack , it's done differently in rails way. avoid service objects if don't need them.

class food < activerecord::base   validates_presence_of :calories    has_many :lists, through: :food_lists, :dependent: :destroy end  class foodlist < activerecord::base   belongs_to :food   belongs_to :list   validates_presence_of: :amount, :food, :list end  class list < activerecord::base   has_many :food_lists   has_many :foods, through: :food_lists, dependent: :destroy    def total_calories     self.food_lists.map{|fl| fl.amount * fl.food.calories}.sum   end end 

things can calculated on fly, should calculated, store them form of optimization if really need to. makes business domain easier debug , support. maintaining state last resort!