Rails 4 Strong Params has_many with JSON

Question

I\'m attempting to pass json up on the client side and have rails take care of handling the object creation.

Here are my models:

class Order < ActiveR         


        

Answer 1

The workaround is not necessary in this case. ActiveRecord provides an automagic way of creating child elements directly through the params hash. In order to accomplish this, follow the steps bellow:

1. Configure Nested Attributes in the model

   class Order < ActiveRecord::Base
     # autosave is already enabled with accepts_nested_attributes_for
     has_many :order_items
     belongs_to :menu_session
   
     accepts_nested_attributes_for :order_items
   end
   

2. Include a *_attributes key in your JSON. In your case, change the order_items key to order_items_attributes

   {'order': {'comments': 'none', 'menu_session_id': '9', 'order_items_attributes':[{'menu_item_id': '5'}, {'menu_item_id': '5'}]}};
   

3. In your controller, make permit accept your new key

   def order_params
     params.require(:order).permit(:comments, :menu_session_id, :order_items_attributes => [:menu_item_id])   
   end
   

There is some more awesomeness possible to accomplish with Nested Attributes. For further information, see ActiveRecord::NestedAttributes at Rails API