adding my comment system to the index page - ruby-on-rails

Question

i have a comment system associated to a shipment model in my app where a user can have many shipments and a shipment can have many comments.
Everything is working perfectly the only problem is that i want my whole comment system to be shown in the index page of my model currently it is in the show page.
when i try to put it on the index page i get an error:
undefined method `comments' for nil:NilClass
My Controllers
shipment_controller.rb
class ShipmentsController < ApplicationController
before_action :set_shipment, only: [:show, :edit, :update, :destroy]
before_action :authenticate_user!
# GET /shipments
# GET /shipments.json
def index
#shipments = Shipment.all
end
# GET /shipments/1
# GET /shipments/1.json
def show
#comments = Comment.where(shipment_id: #shipment)
end
# GET /shipments/new
def new
#shipment = Shipment.new
end
# GET /shipments/1/edit
def edit
end
# POST /shipments
# POST /shipments.json
def create
#shipment = current_user.shipments.new(shipment_params)
respond_to do |format|
if #shipment.save
format.html { redirect_to #shipment, notice: 'Shipment was successfully created.' }
format.json { render :show, status: :created, location: #shipment }
else
format.html { render :new }
format.json { render json: #shipment.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /shipments/1
# PATCH/PUT /shipments/1.json
def update
respond_to do |format|
if #shipment.update(shipment_params)
format.html { redirect_to #shipment, notice: 'Shipment was successfully updated.' }
format.json { render :show, status: :ok, location: #shipment }
else
format.html { render :edit }
format.json { render json: #shipment.errors, status: :unprocessable_entity }
end
end
end
# DELETE /shipments/1
# DELETE /shipments/1.json
def destroy
#shipment.destroy
respond_to do |format|
format.html { redirect_to shipments_url, notice: 'Shipment was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_shipment
#shipment = Shipment.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def shipment_params
params.require(:shipment).permit(:name, :description, :from, :to, :date, :pay)
end
end
comments_controller.rb
class CommentsController < ApplicationController
before_action :authenticate_user!
def create
#shipment = Shipment.find(params[:shipment_id])
#comment = Comment.create(params[:comment].permit(:content))
#comment.user_id = current_user.id
#comment.shipment_id = #shipment.id
if #comment.save
redirect_to shipment_path(#shipment)
else
render 'new'
end
end
end
My routes
Rails.application.routes.draw do
devise_for :users, :controllers => {:registrations => "registrations"}
resources :shipments do
resources :comments
end
root 'shipments#index'
end
Shipment View
show.html.erb
<p id="notice"><%= notice %></p>
<p>
<strong><%= current_user.full_name %></strong>
</p>
<p>
<strong>Description:</strong>
<%= #shipment.description %>
</p>
<p>
<strong>From:</strong>
<%= #shipment.from %>
</p>
<p>
<strong>To:</strong>
<%= #shipment.to %>
</p>
<p>
<strong>Date:</strong>
<%= #shipment.date %>
</p>
<p>
<strong>Pay:</strong>
<%= #shipment.pay %>
</p>
<div id="comments">
<h2 class="comment_count">
<%= pluralize(#shipment.comments.count, "comment") %>
</h2>
<% #comments.each do |comment| %>
<div class="comment">
<p class="full_name">
<%= comment.user.full_name %>
</p>
<p class="content">
<%= comment.content %>
</p>
</div>
<% end %>
<%= render "comments/form" %>
</div>
<%= link_to 'Edit', edit_shipment_path(#shipment) %> |
<%= link_to 'Back', shipments_path %>
Comments View render
_form.html.erb
<%= simple_form_for([#shipment, #shipment.comments.build]) do |f| %>
<%= f.input :content, label: "Reply to thread" %>
<%= f.button :submit, class: "button" %>
<% end %>
index.html.erb without comments
<h1>Listing Shipments</h1>
<%= link_to "Post a new Shipment", new_shipment_path, class: "btn btn-success" %>
<% #shipments.each do |shipment| %>
<div class="shipment">
<h3><strong><%= shipment.user.full_name%></strong></h3>
<h5><strong>DESCRIPTION: </strong><%= shipment.description %></h5>
<div class="meta">
<%= link_to time_ago_in_words(shipment.created_at) + " ago" %> |
<%= link_to "show", shipment %>
<span class="admin">
| <%= link_to "Edit", edit_shipment_path(shipment) %> |
<%= link_to "Delete", shipment, method: :delete, data: { confirm: "Hey! Are you sure! You wanna delete this shipment??"} %>
</span>
</div>
</div>
<% end %>
index.html.erb with comment system
<h1>Listing Shipments</h1>
<%= link_to "Post a new Shipment", new_shipment_path, class: "btn btn-success" %>
<% #shipments.each do |shipment| %>
<div class="shipment">
<h3><strong><%= shipment.user.full_name%></strong></h3>
<h5><strong>DESCRIPTION: </strong><%= shipment.description %></h5>
<div class="meta">
<%= link_to time_ago_in_words(shipment.created_at) + " ago" %> |
<%= link_to "show", shipment %>
<span class="admin">
| <%= link_to "Edit", edit_shipment_path(shipment) %> |
<%= link_to "Delete", shipment, method: :delete, data: { confirm: "Hey! Are you sure! You wanna delete this shipment??"} %>
</span>
</div>
</div>
<div id="comments">
<h2 class="comment_count">
<%= pluralize(#shipment.comments.count, "comment") %>
</h2>
<% #comments.each do |comment| %>
<div class="comment">
<p class="full_name">
<%= comment.user.full_name %>
</p>
<p class="content">
<%= comment.content %>
</p>
</div>
<% end %>
<%= render "comments/form" %>
<% end %>
After Pavan's Answer
Error
ActiveRecord::RecordNotFound (Couldn't find Shipment with 'id'=):
app/controllers/shipments_controller.rb:9:in `index'
Rendered C:/RailsInstaller/Ruby2.0.0/lib/ruby/gems/2.0.0/gems/actionpack-4.2.3
/lib/action_dispatch/middleware/templates/rescues/_source.erb (1.0ms)
Rendered C:/RailsInstaller/Ruby2.0.0/lib/ruby/gems/2.0.0/gems/actionpack-4.2.3
/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb (3.0ms)
Rendered C:/RailsInstaller/Ruby2.0.0/lib/ruby/gems/2.0.0/gems/actionpack-4.2.3
/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb
(1.0ms)
Rendered C:/RailsInstaller/Ruby2.0.0/lib/ruby/gems/2.0.0/gems/actionpack-4.2.3
/lib/action_dispatch/middleware/templates/rescues/diagnostics.html.erb within re
scues/layout (36.0ms)
Rendered C:/RailsInstaller/Ruby2.0.0/lib/ruby/gems/2.0.0/gems/web-console-2.2.
1/lib/web_console/templates/_markup.html.erb (1.0ms)

Answer 1

You've got an ivar #comments that doesn't appear to be defined...Try #shipment.comments.each

Answer 2

I want my whole comment system to be shown in the index page of my
model currently it is in the show page
You need to loop through #shipments in the index view like below
<% #shipments.each do |shipment| %>
<% shipment.comments.each do |comment| %>
----rest of the code---
<% end %>
<% end %>
Update:
You are getting the error here in this line <%= pluralize(#shipment.comments.count, "comment") %>. You just need to change it to
<%= pluralize(shipment.comments.count, "comment") %>
And you need to modify the comments iteration part like I said above.