Ruby on Rails blog and adding comments to posts and editing and deleting comments

I'm working on a ROR blog and have encountered some issues along the way. I'm currently learning Rails and just feel completely lost with connecting all the pieces. I've been working on my comments section for days and was finally able to create comments on posts, but I can't edit or delete them. I also referenced the SO questions below but am still running into problems.

Here's my layout:

Comment model params:

body user_id post_id

Model associations:

user.rb

has_many :posts
has_many :comments

post.rb

belongs_to :user
has_many :comments

comment.rb

belongs_to :user
belongs_to :post


routes.rb:

Rails.application.routes.draw do
# For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html

get '/' => 'users#index'

get '/posts' => 'posts#index'

post '/posts/create' => 'posts#new'

post '/posts/edit' => 'posts#edit'

get '/signin' => 'sessions#new', as: :new_session
post '/create-session' => 'sessions#create', as: :create_session
get 'signout' => 'sessions#destroy', as: :destroy_session

resources :users

resources :posts
resources :comments
end


comments controller:

class CommentsController < ApplicationController

def index
@comment = Comment.all
end

def new
user = session[:user_id]
@comment = Comment.new(post_id: params[:post_id])
@post = Post.find(params[:post_id])
end

def create
@comment = Comment.new(comment_params)
@comment.user_id = session[:user_id]
@postid = params[:id]
if @comment.save
flash[:notice] = "comment created."
redirect_to '/posts'
else
flash[:error] = "Error creating comment."
redirect_to '/posts'
end
end

def edit
@post = Post.find(params[:id])
end

def update
@comment = Comment.find_by_id(params[:id])
@comment.update(comment_params)
flash[:notice] = "Comment updated."
redirect_to '/posts'
end

def destroy
@comment = Comment.find(params[:comment_id])
@comment.destroy
redirect_to '/posts'
end

private

def comment_params
params.require(:comment).permit(:body, :user_id, :post_id)
end
end


Posts show.html.erb page in views/posts folder:

<%# show all posts %>

<div id="single-post">
<h1>User - <%= @post.user.username %></h1>

<h2>Post - <%= @post.body %> </h2>

<%= link_to("Edit Post", edit_post_path(@post)) %>
</br>
<%= link_to("Delete Post", @post, method: 'delete') %>
</br>
<%= link_to("Add Comment", new_comment_path(post_id: @post.id)) %>
<%#<%= link_to("Edit Comment", edit_comment_path(post_id: @post.id, comment_id: @comment.id))%>
</div>


<h3><% @post.comments.reverse.each do |c| %> </h3>
<div id="single-comment">
<h4>Comment</h4>
<h5>From - <%= c.user.username %></h5>

<h6><%= c.body %> </h6>

</br>
<%= link_to("Edit Comment", edit_comment_path(@post.id)) %>
</br>
<%= link_to("Delete Comment", comment_path(@post.id), method: :delete) %>

</div>
<% end %>

</div>


new.html.erb form in views/comments folder

<div id="comment-form">
<%= form_for @comment do |f| %>
<%= f.label :body %>
<%= f.text_area :body, class: "text-area" %>
<%= f.hidden_field :post_id %>
<%= f.submit %>
<% end %>
</div>


Again I can add comments to posts. When I hover over the edit tag on the comment I'm seeing this: localhost:3000/comments/72/edit

I see this error when I click on edit

When I hover over the delete button I see this: localhost:3000/comments/72

I see this error when I click on delete

I'm at the point where I'm completely lost and feel I have tried everything possible but nothing seems to work. Please help! Here's the GitHub repo as well: https://github.com/angelr1076/rails-blog

1 Answer
1

The First argument in form cannot contain nil or be empty is telling you that @comment in <%= form_for @comment do |f| %> is nil. This is because in the edit action of your CommentsController you are setting @post instead of @comment.

First argument in form cannot contain nil or be empty

@comment

<%= form_for @comment do |f| %>

nil

edit

CommentsController

@post

@comment

Change this to be:

def edit
@comment = Comment.find(params[:id])
end


For deleting a comment, the Couldn't find Comment without an ID is telling you that the value you're passing to find is nil. This is because you're trying to use params[:comment_id] instead of params[:id]. Change the destroy action to:

Couldn't find Comment without an ID

find

nil

params[:comment_id]

params[:id]

def destroy
@comment = Comment.find(params[:id])
@comment.destroy
redirect_to '/posts'
end


Update:

Also as per your code, you should change edit and delete links to below

edit

delete

<%= link_to("Edit Comment", edit_comment_path(c)) %>
<%= link_to("Delete Comment", comment_path(c), method: :delete)


You are passing @post.id which is an id of post. Instead you should pass id of the comment using the block variable from your comments.each, noticing that the .id isn't needed here because it can be inferred by Rails.

@post.id

comments.each

.id

params[:post_id]

CommentsController

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