How to link to a nested route action inside a parent loop? - ruby-on-rails

Question

I'm trying to display everything on my index page, but when I try to link to a new_story_substory_path I get undefined local variable or method substory.
Here is the code:
index.html.erb
<% #stories.each do |story| %>
<h3><p><%= story.title %></p></h3>
<p><%= story.plot %></p>
<% if story.user == current_user %>
<%= link_to 'Show XXX', story_path(story), class: "btn btn-success" %>
<%= link_to 'Edit', edit_story_path(story), class: "btn btn-success" %>
<%= link_to "Delete", story_path(story), method: :delete, data: { confirm: "Are you sure?" }, class: "btn btn-success" %></br>
<% end %>
<% story.substories.each do |substory| %>
<h4><p><%= substory.title %></p></h3>
<p><%= substory.subplot %></p>
<% if story.user == current_user %>
<%= link_to 'Show', story_substory_path(substory.story, substory), class: "btn btn-default" %>
<%= link_to 'Edit', edit_story_substory_path(substory.story, substory), class: "btn btn-default" %>
<%= link_to "Delete", story_substory_path(substory.story, substory), method: :delete, data: { confirm: "Are you sure?" }, class: "btn btn-default" %>
<% end %>
<% end %>
<br>
<% if story.user == current_user %>
<br>
<br>
# this is where I'm getting the error:
<%= link_to 'New subplot', new_story_substory_path(substory.story, substory), class: "btn btn-warning" %>
# however if I move this up, inside the second loop, it works perfectly.
<br>
<% end %>
<% end %>
<br>
<%= link_to 'New Story', new_story_path, class: "btn btn-danger" %>
Here is my controller, routes and models:
class StoriesController < ApplicationController
before_action :set_story, only: [:show, :edit, :update, :destroy]
before_action :authenticate_user!, except: [:index, :show]
def index
#stories = Story.all
end
def show
end
def new
#story = current_user.stories.build
end
def edit
end
def create
#story = current_user.stories.build(story_params)
respond_to do |format|
if #story.save
format.html { redirect_to root_path, notice: 'Story was successfully created.' }
format.json { render :show, status: :created, location: root_path }
else
format.html { render :new }
format.json { render json: root_path.errors, status: :unprocessable_entity }
end
end
end
def update
respond_to do |format|
if #story.update(story_params)
format.html { redirect_to root_path, notice: 'Story was successfully updated.' }
format.json { render :show, status: :ok, location: root_path }
else
format.html { render :edit }
format.json { render json: #story.errors, status: :unprocessable_entity }
end
end
end
def destroy
#story.destroy
respond_to do |format|
format.html { redirect_to stories_url, notice: 'Story was successfully destroyed.' }
format.json { head :no_content }
end
end
private
def set_story
#story = Story.find(params[:id])
end
def story_params
params.require(:story).permit(:title, :plot)
end
end
Rails.application.routes.draw do
devise_for :users
resources :stories do
resources :substories
end
root 'stories#index'
end
class Story < ActiveRecord::Base
has_many :substories, dependent: :destroy
belongs_to :user
end
class Substory < ActiveRecord::Base
belongs_to :story
belongs_to :user
end
class User < ActiveRecord::Base
# Include default devise modules. Others available are:
# :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
has_many :stories, dependent: :destroy
has_many :substories, dependent: :destroy
end
what am I missing?
Edit:
Here is the controller for the substories:
class SubstoriesController < ApplicationController
before_action :set_substory, only: [:show, :edit, :update, :destroy]
before_action :authenticate_user!
before_action :set_story
def index
#Substories = #story.substories.all
end
def show
end
def new
#substory = Substory.new
end
def edit
end
def create
#substory = Substory.new(substory_params)
#substory.user_id = current_user.id
#substory.story_id = #story.id
if
#substory.save
redirect_to #story
else
render 'new'
end
end
def update
respond_to do |format|
if #substory.update(substory_params)
format.html { redirect_to root_path, notice: 'Story was successfully updated.' }
format.json { render :show, status: :ok, location: root_path }
else
format.html { render :edit }
format.json { render json: #story.errors, status: :unprocessable_entity }
end
end
end
def destroy
#substory.destroy
redirect_to root_path
end
private
def set_story
#story = Story.find(params[:story_id])
end
def set_substory
#substory = Substory.find(params[:id])
end
def substory_params
params.require(:substory).permit(:title, :subplot)
end
end

Answer 1

I am trying to put this as a comment but I need 50 reputation points to do so. Anyway here is my solution:
The problem is index.html comes from Stories Controller. At this point, you are actually not using any other controllers. This is a common problem at a single page application using ROR. Things do get messy this way.
And you are right, you have to move your error on the second loop. The problem is it would show more than once. That is because there is more than one story. If you want to avoid this, the solution I would say is just make an stories#show show.html.erb. Once you click story, it directs to substroy which then has a plot.

Answer 2

I got the answer from the comments.
MrYoshi wrote:
At the line producing the error: You are calling the substory variable but it is only existing in the story.substories.each loop ; you probably meant to use new_story_substory_path(story) (path leading to the creation page of a substory belonging to the story currently been seen/edited)
Basically I changed the line form:
<%= link_to 'New subplot', new_story_substory_path(substory.story, substory), class: "btn btn-warning" %>
to:
<%= link_to 'New subplot', new_story_substory_path(story), class: "btn btn-warning" %>
This works!