UrlGenerationError in Stores#index - ruby-on-rails

Question

I'm running into what I think is a routing error. I was creating a shopping cart but somehow I'm missing the required key [:product_id]. I believe it may be beginners mistake not placing the right code somewhere.
No route matches {:action=>"add", :controller=>"carts", :product_id=>nil} missing required keys: [:product_id]
app/views/stores/index.html.erb:34:in block in _app_views_stores_index_html_erb__2030225986820803304_70197415655620
app/views/stores/index.html.erb:3:in _app_views_stores_index_html_erb__2030225986820803304_70197415655620
Carts_Controller.rb
class CartsController < ApplicationController
def show
cart_ids = $redis.smembers current_user_cart
#cart_products = Product.find(cart_ids)
end
def add
$redis.sadd current_user_cart, params[:product_id]
render json: current_user.cart_count, status: 200
end
def remove
$redis.srem current_user_cart, params[:product_id]
render json: current_user.cart_count, status: 200
end
private
def current_user_cart
"cart#{current_user.id}"
end
def carts_params
params.require(:cart).permit(:product_id)
end
end
Cart.rb
class Cart < ActiveRecord::Base
belongs_to :user
end
Products_Controller.rb
class ProductsController < ApplicationController
def index
#products = Product.all
#order_item = current_order.order_items.new
end
end
Routes.rb
resource :cart, only: [:show] do
put 'add/:product_id', to: 'carts#add', as: :add_to
put 'remove/:product_id', to: 'carts#remove', as: :remove_from
end
Stores/index.html
<%=link_to "", class: "button", data: {target: #cart_action, addUrl: add_to_cart_path(#product_id), removeUrl: remove_from_cart_path(#product_id)} do%>
<%=#cart_action%>

Answer 1

When you are doing add_to_cart_path(#product_id) it sends the param as :id and you want it to be :product_id.
You can fix this two ways.
Way #1
In your button/link_to change
add_to_cart_path(#product_id)
to:
add_to_cart_path(product_id: #product_id)
Way #2
You can update your controller and route to expect and use the param id instead of product_id