Template is missing error even if I have done a redirect_to in the controller

Question

I just started learning Ruby on Rails from Agile Web Development With Rails.

Doing a shopping cart application and in the process of implementing the "Empty Cart" feature.

<%= button_to 'Empty cart', @cart, method: :delete,
data: { confirm: 'Are you sure?' } %>

Clicking on the 'Empty Cart' button calls the destroy action in the carts controller

# DELETE /carts/1
# DELETE /carts/1.json

def destroy
  @cart = current_cart
  @cart.destroy
  @session[:cart_id] = nil

 respond_to do |format|
  format.html { redirect_to store_url, notice: 'Your cart is currently empty' }
  format.json { head :no_content }
 end
end

Here I redirect it to the store_url but instead it gives me an error.

Template is missing Missing template carts/destroy, application/destroy with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder, :raw, :ruby, :jbuilder, :coffee]}. Searched in: * "/Users/anil20787/workspace/railsdir/depot/app/views"

Here is the output for rake routes

    Prefix Verb   URI Pattern                    Controller#Action
line_items GET    /line_items(.:format)          line_items#index
           POST   /line_items(.:format)          line_items#create


new_line_item GET    /line_items/new(.:format)      line_items#new

edit_line_item GET    /line_items/:id/edit(.:format) line_items#edit

 line_item GET    /line_items/:id(.:format)      line_items#show
           PATCH  /line_items/:id(.:format)      line_items#update
           PUT    /line_items/:id(.:format)      line_items#update
           DELETE /line_items/:id(.:format)      line_items#destroy

     carts GET    /carts(.:format)               carts#index
           POST   /carts(.:format)               carts#create

  new_cart GET    /carts/new(.:format)           carts#new

 edit_cart GET    /carts/:id/edit(.:format)      carts#edit

      cart GET    /carts/:id(.:format)           carts#show
           PATCH  /carts/:id(.:format)           carts#update
           PUT    /carts/:id(.:format)           carts#update
           DELETE /carts/:id(.:format)           carts#destroy

   store_index GET    /store/index(.:format)         store#index

  products GET    /products(.:format)            products#index
           POST   /products(.:format)            products#create

   new_product GET    /products/new(.:format)        products#new

  edit_product GET    /products/:id/edit(.:format)   products#edit

   product GET    /products/:id(.:format)        products#show
           PATCH  /products/:id(.:format)        products#update
           PUT    /products/:id(.:format)        products#update
           DELETE /products/:id(.:format)        products#destroy

     store GET    /                              store#index

I did look at this and this posts which are similar to my problem. But I could not figure out what needs to be done.

Any help in fixing this issue is appreciated.

Edit: - Added {} around redirect_to - Added 'rake routes' output

Answer 1

Ok. I made a mistake in understanding the working and ignored some details while following the tutorial book. Below is my CartsController (partial) and the reason for the error

class CartsController < ApplicationController
before_action :set_cart, only: [:show, :edit, :update, :destroy]
 ..

  # DELETE /carts/1
  # DELETE /carts/1.json
  def destroy
    @cart = current_cart
    @cart.destroy
    @session[:cart_id] = nil


    respond_to do |format|
      format.html { redirect_to store_url, notice: 'Your cart is currently empty' }
      format.json { head :no_content }
    end
  end

  private
    # Use callbacks to share common setup or constraints between actions.
    def set_cart
      begin
        @cart = Cart.find(params[:id])
      rescue ActiveRecord::RecordNotFound
        logger.error "Attempt to access invalid cart #{params[:id]}"
        redirect_to store_url, notice: 'Invalid cart'
      else
        respond_to do |format|
          format.html # show.html.erb
          format.json { render json: @cart }
        end
      end
    end

    # Never trust parameters from the scary internet, only allow the white list through.
    def cart_params
      params[:cart]
    end
end

Why the problem:

The helper method "set_cart" should not send back a response by itself on success. If it sends a response the action action will not be executed at all. So it should just try and fetch the current cart and save it in the @cart instance variable. My set_cart method actually tries to send back a response. It is this response attempt that is raising the error.

I have a filter for my controller which invokes 'set_cart" before destroy.The "set_cart" method tries to send back a HTML response and in the course searches for a destroy.html.erb view which is not present and results in missing view exception.

Answer 2

Try using the follwoing syntax:

class CartsController < ApplicationController
  respond_to :html, :json

  def destroy
    @cart = current_cart
    @cart.destroy
    @session[:cart_id] = nil

    flash[:notice] = "Your cart is currently empty"
    respond_with @cart
  end
end