Tengo ActiveRecord :: AssociationTypeMismatch en el modelo save

Question

Tengo un problema al guardar el modelo con mi API de descanso. Tengo un modelo de tarjeta con muchas tareas y uno de los clientes asociados:

class Card < ActiveRecord::Base 
    belongs_to :customer 

    has_many :card_tasks 
    has_many :tasks, :through => :card_tasks 

    accepts_nested_attributes_for :tasks 
    accepts_nested_attributes_for :card_tasks 
    accepts_nested_attributes_for :customer 

end 


class CardTask < ActiveRecord::Base 
    belongs_to :task 
    belongs_to :card 

    accepts_nested_attributes_for :task 
    accepts_nested_attributes_for :card 
end 

class Task < ActiveRecord::Base 
    has_many :cards, :through => :card_tasks 
    has_many :card_tasks 
end 

Cuando envío un JSON como esto:

{ 
    "card" = > { 
     "miscellaneous" = > "Obervations diverses", 
     "heater" = > "0", 
     "water_quality" = > "", 
     "customer" = > { 
      "id" = > "2", "house_name" = > "house_name2", "city" = > "city_2", "lastname" = > "lastname2", "sci" = > "sci2", "postal_code" = > "potal_code_2", "address_line_1" = > "address_line_2", "updated_at" = > "2012-03-05 18:20:57 +0000", "created_at" = > "2012-03-05 18:20:54 +0000", "firstname" = > "firstname2", "address_line_2" = > "address_line_3", "water_used" = > "0" 
     }, 
     "tasks" = > [ 
      { 
      "title" = > "Nettoyage ligne eau", "id" = > "6", "updated_at" = > "2012-02-17 08:40:47 +0000", "created_at" = > "2012-02-17 08:40:47 +0000" 
      }, 
      { 
      "title" = > "Surveillance", "id" = > "4", "updated_at" = > "2012-02-17 08:40:47 +0000", "created_at" = > "2012-02-17 08:40:47 +0000" 
      } 
     ] 
    } 
} 

Mi crear la acción:

def create 
     card = Card.new(params[:card]) 
     if (card.save) 
     respond_with({ :card => card} , :location => nil, status: :created) and return 
     end 
     respond_with({ :errors => card.errors }, :location => nil, status: :unprocessable_entity) and return 
    end 

Al hacer esto, Tengo un:

ActiveRecord::AssociationTypeMismatch (Task(#70249431354580) expected, got ActiveSupport::HashWithIndifferentAccess(#70249421573300)): 
    app/controllers/cards_controller.rb:14:in `new' 
    app/controllers/cards_controller.rb:14:in `create' 

W ¿Qué hice mal?

Answer 1

El problema está en la estructura JSON, Rails espera tasks_attributes, no tasks. Compruebe this question para más detalles.