I am trying out a commenting system in a way described by ryanb in https://github.com/railscasts/154-polymorphic-association/tree/master/revised/blog-after.
It uses Rails 3 nested resource routing seen in routes.rb:
resources :articles do
resource :comments
end
Comments are loaded by parents type and id as seen in articles_controller.rb and comments_controller.rb:
class ArticlesController < ApplicationController
...
def show
#article = Article.find(params[:id])
#commentable = #article
#comments = #commentable.comments
#comment = Comment.new
end
class CommentsController < ApplicationController
before_filter :load_commentable
def index
#comments = #commentable.comments
end
...
private
def load_commentable
resource, id = request.path.split('/')[1, 2]
#commentable = resource.singularize.classify.constantize.find(id)
end
...
end
How would I go about adding a link to a comments edit or destroy actions in comments' view template?
_comments.html.erb:
<% #comments.each do |comment| %>
<div class="comment">
<%= simple_format comment.content %>
<%= link_to "Delete", comment, method: :delete %>
</div>
<% end %>
Pass resources as an array:
<%= link_to "Delete", [#article, #comment], method: :delete %>
With jdoes advice I looked more into the array passing and noticed routes.rb was missing an s from resources :comments. Fixed version:
resources :articles do
resources :comments do
end
end
Now the template works perfectly just by giving the link as an array.
<% #comments.each do |comment| %>
<div class="comment">
<%= simple_format comment.content %>
<%= link_to "Delete", [#commentable, comment], method: :delete %>
</div>
<% end %>
Related
I have a rails question. I'm building a site where posts have likes, both posts and likes are their own model. A user can only like a post once, and once they like it the like button becomes an "unlike" button, that deletes the like.
I'm trying to create an experience in which the user can like, or unlike a post - and will not be redirected, but the like will update. With my limited rails knowledge, this isn't an easy task. Can anyone point me in the right direction?
Here is my /likes/_likes.html.erb template partial with the like/unlike button:
<% liked = #post.likes.find { |like| like.user_id == current_user.id} %>
<div class="likes">
<% if liked %>
<%= button_to 'Unlike', post_like_path(#post, liked), method: :delete %>
<% else %>
<%= button_to 'Like', post_likes_path(#post), method: :post %>
<% end %>
<%= #post.likes.count %><%= (#post.likes.count) == 1 ? 'Like' : 'Likes'%>
</div>
Here is my Like controller:
class LikesController < ApplicationController
before_action :find_post
before_action :find_like, only: [:destroy]
def create
if (!already_liked?)
#post.likes.create(user_id: current_user.id)
end
end
def destroy
if (already_liked?)
#like.destroy
end
end
private
def already_liked?
Like.where(user_id: current_user.id, post_id:
params[:post_id]).exists?
end
def find_post
#post = Post.find(params[:post_id])
end
def find_like
#like = #post.likes.find(params[:id])
end
end
Here is one of the views in which the _likes partial shows up (although the issue persists everywhere it appears):
<div class="post-display">
<% if #post.title %>
<h1><%= #post.title %></h1>
<% end %>
<% if #post.user %>
Post by <%= #post.user.email %>
<% end %>
<% if #post.price %>
<p>$<%= sprintf "%.2f", #post.price %></p>
<% end %>
<% if #post.description %>
<p><%= #post.description %></p>
<% end %>
<% if #post.image.present? %>
<%= image_tag #post.image.variant(:small) %>
<% end %>
<%= render 'likes/likes' %>
</div>
<% if current_user == #post.user %>
<%= link_to "Edit", edit_post_path(#post) %>
<%= button_to "Delete", #post, method: :delete %>
<% end %>
<% if #post.comments.count > 0 %>
<div class="post-comments">
<h2 class="post-comments-headline">Comments</h2>
<%= render #post.comments %>
</div>
<% end %>
<h2>Add a comment:</h2>
<%= render 'comments/form' %>
If you don't have an answer to my question, but have an idea on how to improve my code - let me know either way! I'm trying to learn here...
Thank you,
Jill
Since you're using rails 7, rendering turbo_stream in response to "like" and "unlike" buttons will update the page without refreshing.
# config/routes.rb
resources :posts do
# NOTE: i've used singular `resource`, since there is no need to have `id`
# for the like.
resource :like, only: [:destroy, :create]
end
https://api.rubyonrails.org/classes/ActionDispatch/Routing/Mapper/Resources.html#method-i-resource
# app/models/post.rb
class Post < ApplicationRecord
has_many :likes
def liked_by? user
likes.where(user: user).exists?
end
end
# app/models/like.rb
class Like < ApplicationRecord
belongs_to :post
belongs_to :user
# NOTE: avoid double likes.
validates_uniqueness_of :user, scope: :post, message: "already liked this post"
# TODO: create a unique index migration, to really make sure no double likes.
# `add_index :likes, [:post_id, :user_id], unique: true`
end
I've simplified LikesController a bit. No need for before_action filters:
# app/controllers/likes_controller.rb
class LikesController < ApplicationController
# POST /posts/:post_id/like
def create
# NOTE: uniqueness validation in `Like` model will prevent creating dup likes.
post.likes.create(user: current_user)
# you can access `like` error if you want to show it:
# like = post.likes.create(user: current_user)
# like.errors.full_messages
# NOTE: that's it, now we render `likes` partial inside a `turbo_stream`
render turbo_stream: turbo_stream.replace(
helpers.dom_id(post, :like), # this is the target div `id` that will be replaced
partial: "posts/likes", # with `likes` partial.
locals: { post: post }
)
end
# DELETE /posts/:post_id/like
def destroy
# NOTE: this will work regardless if there are any likes or not.
post.likes.where(user: current_user).destroy_all
# NOTE: alternatively, we can render the same `turbo_stream` as above
# in a template `likes/likes.turbo_stream.erb`:
render :likes
end
private
def post
#post ||= Post.find params[:post_id]
end
end
<!-- app/views/posts/_likes.html.erb -->
<!-- `dom_id` helps us generate a uniq id: "like_post_1" -->
<div id="<%= dom_id(post, :like) %>">
<!-- yes, there is a rails helper for this -->
<%= pluralize post.likes.count, "like" %>
<% if post.liked_by? current_user %>
<%= button_to "Unlike", post_like_path(post), method: :delete %>
<% else %>
<%= button_to "Like", post_like_path(post) %>
<% end %>
</div>
This turbo_stream is the same as in create action:
<!-- app/views/likes/likes.turbo_stream.erb -->
<%= turbo_stream.replace dom_id(#post, :like) do %>
<%= render "posts/likes", post: #post %>
<% end %>
https://turbo.hotwired.dev/handbook/streams
Try this
views file where likes partial render
<div id='post_likes'>
<%= render 'likes/likes' %>
</div>
/likes/_likes.html.erb
<div class="likes">
<% if liked %>
<%= button_to 'Unlike', post_like_path(#post, liked), method: :delete, remote: true %>
<% else %>
<%= button_to 'Like', post_likes_path(#post), method: :post, remote: true %>
<% end %>
<%= #post.likes.count %><%= pluralize(#post.likes.count, 'Like') %>
</div>
views/likes/create.js.erb
$('#post_likes').html('<%= render 'likes/likes' %>');
views/likes/destroy.js.erb
$('#post_likes').html('<%= render 'likes/likes' %>');
Currently learning Ruby on Rails and creating a simple blog app with comments. I have a Comment model and an Article model. Comment is polymorphic and both models have many comments.
I'm trying to come up with a destroy method that's able to delete both the comments that belong to Comment and the ones that belong to Article (and that remain as [deleted] without destroying their children, much like in Reddit, although I haven't even gotten to that part).
I have tried different paths but I haven't got it right yet. Nested paths still confuse me a little and I'm not sure on how to pass the params that the path requests when creating the link_to.
These are my files:
routes.rb:
Rails.application.routes.draw do
get 'comments/new'
get 'comments/create'
get 'articles/index'
get 'articles/show'
root 'articles#index'
resources :articles do
resources :comments
end
resources :comments do
resources :comments
end
end
article.rb:
class Article < ApplicationRecord
has_many :comments, as: :commentable
end
comment.rb:
class Comment < ApplicationRecord
belongs_to :commentable, polymorphic: :true
has_many :comments, as: :commentable
end
comments_controller.rb:
class CommentsController < ApplicationController
before_action :find_commentable
def new
#comment = Comment.new
end
def create
#comment = #commentable.comments.new(comment_params)
if #comment.save
redirect_back(fallback_location: root_path)
else
redirect_back(fallback_location: root_path)
end
end
def destroy
#comment = #commentable.comments.find(params[:id])
#comment.destroy
redirect_back(fallback_location: root_path)
end
private
def comment_params
params.require(:comment).permit(:body)
end
def find_commentable
if params[:article_id]
#commentable = Article.find_by_id(params[:article_id])
elsif params[:comment_id]
#commentable = Comment.find_by_id(params[:comment_id])
end
end
end
show.html.erb, where the form for commments that belong to Article.rb is:
<h1> <%= #article.title %> </h1>
<p> <%= #article.body %> </p>
<small>Submitted <%= time_ago_in_words(#article.created_at) %> ago </small> <br/>
<h3>Comments</h3>
<%= form_for [#article, Comment.new] do |f| %>
<%= f.text_area :body, placeholder: "Say something!" %> <br/>
<%= f.submit "Submit" %>
<% end %>
<ul class="parent-comment">
<%= render partial: 'comments/comment', collection: #article.comments %>
</ul>
<%= link_to "Index", articles_path %>
And the partial _comment.html.erb , which displays the comments that belong to the article as well as those that belong to other comments, and where I'm trying to integrate the link_to:
<p> <%= comment.body %> </p>
<small>Submitted <%= time_ago_in_words(comment.created_at) %> ago </small> <br/>
<%= form_for [comment, Comment.new] do |f| %>
<%= f.text_area :body, placeholder: "Add a reply!" %><br/>
<%= f.submit "Reply" %>
<%= link_to "Delete", comment_path(comment), method: :delete %>
<% end %>
<ul>
<%= render partial: 'comments/comment', collection: comment.comments %>
</ul>
Whenever I do seem to get the path right, NoMethodError in CommentsController#destroy — undefined method `comments' for nil:NilClass comes up. Why would the controller show it as undefined? It worked in the new method, as far as I can see.
Could you give some guidance as to what I should do or what I should fix? I'm not sure how to delete the parent comments, either, and I haven't managed to find information that suits this case. If you know where to point me to, I'm all eyes.
Thank you.
Because of your design model structure.
Your view
<%= link_to "Delete", comment_path(comment), method: :delete %>
Your find_commentable
elsif params[:comment_id]
#commentable = Comment.find_by_id(params[:comment_id])
end
#commentable will be a Comment class, so it won't have .comments methods as your Article class
check carefully to destroy the method
def destroy
#comment = #commentable.comments.find(params[:id])
#comment.destroy
redirect_back(fallback_location: root_path)
end
use #comment = #commentable.comments.find_by(id: params[:id]) and check whether #comment has some value or not?
just add one condition like this and it won't throw the error:
#comment.destroy if #comment
if #comment is nil and trying to destroy then it will throw the error.
so I'm trying to create a video game review website for practice.
A game has many reviews, and votes. The idea is, in order to post a review, you must vote "Good" or "Bad" first, THEN submit a review. You can't post a text review without voting.
I'm trying to do this without the acts_as_voteable gem...
The data format for votes is boolean. "Good" is true, "Bad" is false.
How do I get the votes to save? below are my routes.rb, _review partial, reviews controller, and show page.
many thanks guys :)
edit****: also I'm trying to only one vote per user. I was thinking of using a token variable which equals to 1, and when a vote is cast, the token is -1. Is that a good approach? But the data type for vote is boolean, so how would that work -- or should I change the data type for vote from boolean to integer?
edit#2 -- so I added :vote into my params.
routes.rb
upvote_game_review_path
POST /games/:game_id/reviews/:id/upvote(.:format) reviews#upvote
downvote_game_review_path
POST /games/:game_id/reviews/:id/downvote(.:format) reviews#downvote
Rails.application.routes.draw do
devise_for :users
root "games#index"
resources :games do
resources :news
resources :reviews, except: [:show, :index] do
member do
post "upvote"
post "downvote"
end
end
end
resources :platforms
resources :genres
end
reviews_controller.rb
class ReviewsController < ApplicationController
before_action :set_review, only: [:show, :update, :edit, :destroy]
before_action :set_game
before_action :authenticate_user!
def new
#review = Review.new
end
def create
#review = Review.new(review_params)
#review.user_id = current_user.id
#review.game_id = #game.id
if #review.save
redirect_to #game
else
render "review"
end
end
def upvote
#review.vote.create = true
redirect_to #game
end
def downvote
#review.vote.create
#review.vote = false
redirect_to #game
end
def edit
#review.update(review.params)
end
def destroy
#review.destroy
redirect_to #game
end
private
def set_review
#review = Review.find(params[:id])
end
def set_game
#game = Game.find(params[:game_id])
end
def review_params
params.require(:review).permit(:comment, :vote)
end
end
_review partial <-- to create a new review
<%= form_for [#game, #reviews.new] do |r| %>
<h3 class="post_review">Review this game</h3>
<p>
<%= r.text_area :comment %>
</p>
<p>
<%= button_to "Good", upvote_game_review_path(#game.id, r) %>
</p>
<p>
<%= button_to "Bad", downvote_game_review_path(#game.id, r) %>
</p>
<p>
<%= r.hidden_field :game_id, value: #game.id %>
<p>
<%= r.submit %>
<% end %>
show.html.erb
<p><%= link_to "<< Home", games_path %></p>
<span><%= link_to "Edit", edit_game_path(#game) %></span>
<span><%= link_to "Delete", game_path(#game), method: :delete %></span>
<div class="game_summary">
<h2><%= #game.title %></h2>
<%= image_tag #game.image %>
<p>Release Date: <%= #game.release_date %> </p>
<p>Genre: <%= #game.genre_id %> </p>
<p>Platforms: <%= #game.platform_id %></p>
</div>
<%= link_to "Add News", new_game_news_path(#game) %>
<h2>News & Articles</h2>
<%= link_to "view all", game_news_index_path(#game) %>
<% #news.each do |n| %>
<ol>
<li><%= link_to n.title, game_news_path(#game.id, n.id) %></li>
</ol>
<% end %>
<div class="game_review submit">
<%= render "review" %>
</div>
<% #reviews.each do |review| %>
<p><%= review.comment %></p>
<p><%= link_to "delete", game_review_path(#game.id, review.id), method: :delete %></p>
<% end %>
You don't specify which review you're loading in. The reason is here:
before_action :set_review, only: [:show, :update, :edit, :destroy]
You don't pull in the request's review instance when you go to either of those actions. Further, it doesn't look like you're actually saving them.
So, two things I'd recommend:
Add those methods to your before_action:
before_action :set_review, only: [:show, :update, :edit,
:destroy, :upvote, :downvote]
(May not be necessary, write tests to confirm this!) Actually save the entity after you've changed its value.
def upvote
#review.vote.create = true
#review.save
redirect_to #game
end
def downvote
#review.vote.create unless #review.vote
#review.vote = false
#review.save
redirect_to #game
end
I've been trying to get the ancestry gem for rails to work but I seem to fail at implementing even the most simplest case. I'm new to rails so I could easily be making a rookie mistake.
What I was trying to implement was just a normal commenting system where replies to comments would be shown all on the same page using ancestry's child/parent functionality.
Below is my show html which has a reply link which is where I am trying to set up the parent child relationship:
<p id="notice"><%= notice %></p>
<%=#comment.children.nil?%>
<p>
<strong>Body:</strong>
<%= #comment.body %>
</p>
<p>
<%if !#children.nil?%>
<% #children.each do |c|%>
c.body
<%end%>
<%end%>
</p>
<p>
<strong>Author:</strong>
<%= #comment.author %>
</p>
<%= link_to 'Reply', new_comment_path, :parent_id => #comment %>
<%= link_to 'Edit', edit_comment_path(#comment) %> |
<%= link_to 'Back', comments_path %>
And here is some of the controller methods:
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
#children=#comment.children
end
# GET /comments/new
def new
#parent_id = params.delete(:parent_id)
#comment = Comment.new(:parent_id => #parent_id)
end
//omitted code
private
# Use callbacks to share common setup or constraints between actions.
def set_comment
#comment = Comment.find(params[:id])
end
I can not seem to get any parent/child relationship with the above code
ok I figured it out in the end. I was only passing the parent parameter to the "new" controller method, I should have been passing it again after this at the create stage. Was a silly mistake.
Hi this is my first time using nested resources. I did rake routes and found a path to new_user_album_path, but it doesn't seem to work. Could the problem be because I did a double nest?
The problem is specifically when I click a link in my Users views file named show.html.erb . Trying to link to a "create an album" page but that's when it shows me an error:
No route matches {:action=>"new", :controller=>"albums"}
Here are my files:
show.html.erb
<% provide(:title, "Welcome, #{#user.name}!") %>
<div>
You currently have <%= pluralize(#user.albums.count, "album") %>
</div>
<div>
<%= link_to "Create a new album!", new_user_album_path %>
</div>
<div>
<% if #user.albums.any? %>
hey
<% else %>
boo
<% end %>
</div>
<%= link_to "Back", users_path %>
Config/routes
Pholder::Application.routes.draw do
resources :users do
resources :albums do
resources :pictures
end
end
Controller
class AlbumsController < ApplicationController
def index
#albums = Albums.all
respond_to do |format|
format.html
format.json { render json: #albums }
end
end
def new
#user = User.find(params[:user_id])
end
end
You need to pass the user to the route method, like:
new_user_album_path(#user)