ActionController::UrlGenerationError in Images#index - html

Question

newbie here stuck on nested resources. I have a image.rb model, which stores images onto the cloudinary CDN. After getting all that working, I decided I needed to categorize the images, so i created a category.rb model which just has a name really, for now anyways.
I have been slowly working through errors after adding a category model and controller/views and all was going okay, until this one. I'm stumped lol. Have been googling around for a few hours now and decided I'm at a wall... so, naturally I come here, hoping someone could enlighten me. Thanks in advance! <3 SO
Here is the error (it is currently throwing it on the "edit" link, but i think it will throw it on the "delete" as well after i get edit working, so I have been changing them there as well):
No route matches {:category_id=>nil, :id=>#<Image id: 16, title: "mario", description: "i belong to category 2!", upload_date: nil, created_at: "2014-03-15 01:13:54", updated_at: "2014-03-15 01:13:54", category_id: 2>} missing required keys: [:category_id]
<td><%= link_to "Show", [#category, image] %></td>
<% if admin? %>
<td><%= link_to "Edit", edit_category_image_path(#category, image) %></td>
<td><%= link_to "Delete", [#category, image], confirm: "Are you sure you want to delete \"#{image.title}\"?", method: :delete %></td>
<% end %>
</tr>
Here is my Image model:
class Image < ActiveRecord::Base
has_attachment :image_file, accept: [:jpg, :png, :gif]
validates :title, presence: true
belongs_to :category
end
Here is the Category model:
class Category < ActiveRecord::Base
has_many :images
end
Here are the controllers for each:
class ImagesController < ApplicationController
before_filter :authenticate_admin, except: [:index, :show]
def index
#images = Image.all
end
def show
#image = Image.find(params[:category_id])
end
def new
#category = Category.find(params[:category_id])
#image = #category.images.build(image_params)
end
def create
#category = Category.find(params[:category_id])
#image = #category.images.build(image_params)
if #image.save
render "show"
else
render "new"
end
end
def destroy
#image = Image.find(params[:id])
#image.destroy
redirect_to images_path
end
def edit
#category = Category.find(params[:category_id])
#image = #category.images.find(params[:id])
end
def update
#category = Category.find(params[:category_id])
#image = #category.images.find(params[:id])
if #image.update(image_params)
render "show"
else
render "edit"
end
end
private
def image_params
params.require(:image).permit(:title, :description, :image_file, :category_id)
end
end
and the Category controller
class CategoriesController < ApplicationController
def index
#categories = Category.all
end
def show
redirect_to category_images_path(params[:id])
end
def new
#category = Category.new
end
def create
#category = Category.new(category_params)
if #category.save
redirect_to #category
else
render "new"
end
end
def destroy
#category = Category.find(params[:id])
#category.destroy
redirect_to categories_path
end
def edit
#category = Category.find(params[:id])
end
def update
#category = Category.find(params[:id])
if #category.update(category_params)
redirect_to #category
else
render "edit"
end
end
private
def category_params
params.require(:category).permit(:title)
end
end
Here is the routes file:
Portfolio::Application.routes.draw do
devise_for :users
resources :blogs
resources :categories do
resources :images
end
root "index#index"
#attachinary
mount Attachinary::Engine => "/attachinary"
end
From googling around I kept running into people having problems with it being related to form partials so here is the _form.html.erb I am using for Image just in case it's needed:
<%= form_for([#category, #image]) do |f| %>
<%= render "error" %>
<p>
<%= f.label :title %>
<br>
<%= f.text_field :title %>
</p>
<p>
<%= f.label :description %><br>
<%= f.text_area :description %>
</p>
<p>
<%= f.label "Upload image" %><br>
<%= f.attachinary_file_field :image_file %>
</p>
<p>
<%= f.submit %>
</p>
<% end %>

Answer 1

ImagesController
class ImagesController < ApplicationController
before_action :load_category
before_action :set_image, only: [:show, :edit, :update, :destroy]
before_filter :authenticate_admin, except: [:index, :show]
def index
#images = #category.images.all
end
def show
end
def new
#image = #category.images.new
end
def create
#image = #category.images.new(image_params)
if #image.save
render "show"
else
render "new"
end
end
def destroy
#image.destroy
redirect_to images_path
end
def edit
end
def update
if #image.update(image_params)
render "show"
else
render "edit"
end
end
private
def load_category
#category = Category.find(params[:category_id])
end
def set_image
#image = #category.images.find(params[:id])
end
def image_params
params.require(:image).permit(:title, :description, :image_file, :category_id)
end
end
Try to use the before_action callback to set your necessary instance variables. Here I loaded the category and the images via a private method. This saves a lot time. You can even see this when you generate scaffolding.
before_filter has been aliased as before_action to make it clearer of its function.
The root path is usually defined on the second line of routes so its clear.
Your named paths doesn't seem like the problem. It is mainly your images controller
I suggest you generate a new rails app using scaffolding just to look at it's controllers.
rails g scaffolding images