Rails - Cannot seem to pass a parameter to a method - ruby-on-rails

Question

I am trying to set up a simple cart. I want to be able to click on 'add' on a record and then have that item added to the cart with the id of the record/line
<% #documents.each do |document| %>
<td><%= link_to "add", add_to_cart_path(8), :method => :post %></td>
<% end %>
I put the add_to_cart_path(8) as a troubleshooting. I really want that to be add_to_cart(document.id) however, either way, the current doc id parameter is not getting passed to the creation of the new item record.
My route is
post '/add_to_cart/:doc_id' => 'carts#add_to_cart', :as => 'add_to_cart'
The carts controller has
def add_to_cart
$current_doc_id = doc_id
current_cart.add_item(:doc_id)
redirect_to carts_path(current_cart.id)
end
my cart model has
def add_item(document_id)
#line_item = Item.create(:document_id => document_id, :cart_id => $cart_number)
if #line_item.save
# flash[:success] = "item added!"
else
# flash[:fail] = "!"
end
end
When I look at the items table, the record is being created and the cart id is properly populated. However, the document_id field is 'null'.

Answer 1

I know you have the answer, but I wanted to clean up your code a bit...
#config/routes.rb
resources :cart, only: [] do
collection do
post "add/:document_id", to: :create #-> url.com/cart/add/:document_id
delete "remove/:document_id", to: :destroy #-> url.com/cart/remove/:document_id
end
end
#app/controllers/cart_controller.rb
class CartController < ApplicationController
before_action :set_document
def create
current_cart.line_items << #document
redirect_to carts_path current_cart.id
end
def destroy
current_cart.line_items.delete #document
redirect_to carts_path current_cart.id
end
private
def set_document
#document = Document.find params[:document_id]
end
end
This would allow you to use:
<%= link_to "Add to Cart", carts_add_path(#document), method: :post %>
<%= link_to "Remove from Cart", carts_remove_path(#document), method: :delete %>
You have a fundamental antipattern in that you're using request-based logic in your Cart model. Models should only be for data-driven logic; request logic all needs to be kept within your controller:
if #line_item.save
# flash[:success] = "item added!"
else
# flash[:fail] = "!"
end
... needs to be in your controller if you're relying on it to form a response.
We've set up a cart before (using a session model). You may benefit from the code we used. It's fundamentally different to yours in that it keeps the cart in a single session cookie, rather than saving the data in a model:
#config/routes.rb
resources :cart do
collection do
post 'cart/add/:id', to: 'cart#add', as: :cart_add
delete 'cart/remove(/:id(/:all))', to: 'cart#delete', as: :cart_delete
end
end
#app/controllers/cart_controller.rb
class CartController < ApplicationController
include ApplicationHelper
#Index
def index
#items = cart_session.cart_contents
end
#Add
def add
session[:cart] ||={}
products = session[:cart][:products]
#If exists, add new, else create new variable
if (products && products != {})
session[:cart][:products] << params[:id]
else
session[:cart][:products] = Array(params[:id])
end
#Handle the request
respond_to do |format|
format.json { render json: cart_session.build_json }
format.html { redirect_to cart_index_path }
end
end
#Delete
def delete
session[:cart] ||={}
products = session[:cart][:products]
id = params[:id]
all = params[:all]
#Is ID present?
unless id.blank?
unless all.blank?
products.delete(params['id'])
else
products.delete_at(products.index(id) || products.length)
end
else
products.delete
end
#Handle the request
respond_to do |format|
format.json { render json: cart_session.build_json }
format.html { redirect_to cart_index_path }
end
end
end
Then to show the cart:
#app/views/cart/index.html.erb
<% #items.each do |item| %>
<%= item.name %>
<% end %>
I'll delete if inappropriate, I figured it would give you some perspective.