Trying to create comments. (Undefined method 'comment') - ruby-on-rails

Question

I am receiving this error and I don't understand as I have defined the method in the comments controller, haven't I?
I am getting slightly confused to why it is not working.
Comments controller:
class CommentsController < ApplicationController
def create
#story = Story.find(params[:story_id])
#comment = #story.comments.create(params[:comment].permit(:name, :body))
redirect_to root_path
end
end
Stories Controller:
class StoriesController < ApplicationController
before_action only: [:destroy, :show, :edit, :update]
def index
#stories = Story.order('created_at DESC')
end
def new
#story = current_user.stories.build
end
def create
#story = current_user.stories.build(story_params)
if #story.save
flash[:success] = "Your beautiful story has been added!"
redirect_to root_path
else
render 'new'
end
end
def edit
#story = Story.find(params[:id])
end
def update
#story = Story.find(params[:id])
if #story.update_attributes(params.require(:story).permit(:name, :description))
flash[:success] = "More knowledge, more wisdom"
redirect_to root_path
else
render 'edit'
end
end
def destroy
#story = Story.find(params[:id])
if #story.destroy
flash[:success] = "I think you should have more confidence in your storytelling"
redirect_to root_path
else
flash[:error] = "Can't delete this story, sorry"
end
end
def show
#stories = Story.all
end
private
def story_params
params.require(:story).permit(:name, :description)
end
end
Index.html.erb:
<p id="notice"><%= notice %></p>
<h1>This is a list of posts</h1>
<table>
<thead>
<tr>
<th>Name</th>
<th>Description</th>
<th>User</th>
<th colspan="3"></th>
</tr>
</thead>
<tbody>
<% #stories.each do |story| %>
<tr>
<td><%= story.name %></td>
<td><%= story.description %></td>
<td><%= story.user.username %></td>
<td><%= link_to 'Show', story %></td>
<% if user_signed_in? %>
<td><%= link_to 'Edit', edit_story_path(story)%></td>
<td><%= link_to 'Destroy', story_path(story),method: :delete,data: { confirm: 'Are you sure?' } %></td>
<% end %>
</tr>
</tbody>
</table>
<h2><%= #story.comments.count %>Comments</h2>
<%= render #story.comments %>
<h3>Add a comment</h3>
<%= render 'comments/form' %>
<%= link_to 'New Story', new_story_path %>
Story Controller:
class CommentsController < ApplicationController
before_action :set_comment, only: [:show, :edit, :update, :destroy]
# GET /comments
# GET /comments.json
def index
#comments = Comment.all
end
# GET /comments/1
# GET /comments/1.json
def show
#comments = #story.comments.all
#comment = #stroy.comments.build
end
# GET /comments/new
def new
#comment = Comment.new
end
# GET /comments/1/edit
def edit
end
# POST /comments
# POST /comments.json
def create
#story = Story.find(params[:story_id])
#story.comments.create(comment_params)
end
# PATCH/PUT /comments/1
# PATCH/PUT /comments/1.json
def update
respond_to do |format|
if #comment.update(comment_params)
format.html { redirect_to #comment, notice: 'Comment was successfully updated.' }
format.json { render :show, status: :ok, location: #comment }
else
format.html { render :edit }
format.json { render json: #comment.errors, status: :unprocessable_entity }
end
end
end
# DELETE /comments/1
# DELETE /comments/1.json
def destroy
#comment.destroy
respond_to do |format|
format.html { redirect_to comments_url, notice: 'Comment was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_comment
#comment = Comment.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def comment_params
params.require(:comment).permit(:user_name, :body, :story_id)
end
end

Answer 1

Make sure you have run the right migrations
rails g scaffold comment user_name:string body:text story:references
now
rake db:migrate
In your story model write
has_many :comments
And in your comment model make sure you have
belongs_to :story
or in your story controller in the show method have this
#comments = #story.comments.all
#comment = #stroy.comments.build
And now in your story form show views, something like this
<h3>Comments</h3>
<% #comments.each do |comment| %>
<div>
<p><%= comment.body %></p>
</div>
<% end %>
<%= render 'comments/form' %>
In your comment/_form.html.erb add
<%= f.hidden_field :story_id %>
If you want to display on your index edit you like so
<tbody>
<% #stories.each do |story| %>
<tr>
<td><%= story.name %></td>
<td><%= story.description %></td>
<td><%= story.user.username %></td>
<td><%= link_to 'Show', story %></td>
<% if user_signed_in? %>
<td><%= link_to 'Edit', edit_story_path(story)%></td>
<td><%= link_to 'Destroy', story_path(story),method: :delete,data: { confirm: 'Are you sure?' } %></td>
<% story.comments.each do |c| %>
<%= c.body %>
<% end %>
<% end %>
</tr>
</tbody>

Answer 2

You have to start by understanding how associations works:
One Story will have many comments.
You have to define the association in the model:
class Story < ActiveRecord::Base
has_many :comments
end
class Comment < ActiveRecord::Base
belongs_to :story
end
Then the methods in the controller will be available:
class CommentsController < ApplicationController
def create
#story = Story.find(params[:story_id])
#story.comments.create(comment_params)
end
end
And in your app/stories/show.html.erb view:
<% #story.comments.each do |comment| %>
<%= comment.body #or the comment content method %>
<% end %>