How to parse nested JSON object in Rails? - ruby-on-rails

Question

I'm sending the following JSON to Rails 4.1.0
Started POST "/orders.json" for 127.0.0.1 at 2015-08-11 15:19:34 +0200
Processing by OrdersController#create as JSON
Parameters: {"order"=>{"name"=>"Jon", "surname"=>"Do", "line_items_attributes"=>[{"work_id"=>16, "quantity"=>1, "total_price"=>34.5}, {"work_id"=>12, "quantity"=>2, "total_price"=>40}]}}
Unpermitted parameters: line_items_attributes
but I'm getting Unpermitted parameters error. My Order model:
class Order < ActiveRecord::Base
belongs_to :user
belongs_to :dispatch_method
belongs_to :payment_method
has_many :line_items, :dependent => :destroy
accepts_nested_attributes_for :line_items
end
My orders_controller.rb
class OrdersController < ApplicationController
before_action :set_order, only: [:show, :edit, :update, :destroy]
def index
#orders = Order.all
end
def show
end
def new
#order = Order.new
end
def edit
end
def create
#order = Order.create(order_params)
respond_to do |format|
if #order.save
format.html { redirect_to #order, notice: 'Order was successfully created.' }
format.json { render action: 'show', status: :created, location: #order }
else
format.html { render action: 'new' }
format.json { render json: #order.errors, status: :unprocessable_entity }
end
end
end
def update
respond_to do |format|
if #order.update(order_params)
format.html { redirect_to #order, notice: 'Order was successfully updated.' }
format.json { head :no_content }
else
format.html { render action: 'edit' }
format.json { render json: #order.errors, status: :unprocessable_entity }
end
end
end
def destroy
#order.destroy
respond_to do |format|
format.html { redirect_to orders_url }
format.json { head :no_content }
end
end
private
def set_order
#order = Order.find(params[:id])
end
def order_params
params.require(:order).permit(:name, :surname, line_items_attributes: [:id, :work_id, :quantity, :total_price])
end
end
I'm able to create and save a new instance of order, but not of a line_item.

Answer 1

You can try to redefine your order_params like this:
def order_params
json_params = ActionController::Parameters.new(JSON.parse(params[:order]))
return json_params.require(:name, :surname).permit(line_items_attributes: [:id, :work_id, :quantity, :total_price])
end
As you see, I am parsing params[:order] to avoid parsing the full params var. You might need to add another json level here but I hope you get the idea.

Answer 2

something like this
render :json => #booking, :include => [:paypal,
:boat_people,
:boat => {:only => :name, :include => {:port => {:only => :name, :include => {:city => {:only => :name, :include => {:country => {:only => :name}}}}},
:boat_model => {:only => :name, :include => {:boat_type => {:only => :name}}}}}]