36. RESTful Controllers

1class ArticlesController < ApplicationController
2  # GET /articles
3  def index
4    @articles = Article.all
5  end
6  
7  # GET /articles/:id
8  def show
9    @article = Article.find(params[:id])
10  end
11  
12  # GET /articles/new
13  def new
14    @article = Article.new
15  end
16  
17  # POST /articles
18  def create
19    @article = Article.new(article_params)
20    
21    if @article.save
22      redirect_to @article, notice: "Article created!"
23    else
24      render :new, status: :unprocessable_entity
25    end
26  end
27  
28  # GET /articles/:id/edit
29  def edit
30    @article = Article.find(params[:id])
31  end
32  
33  # PATCH/PUT /articles/:id
34  def update
35    @article = Article.find(params[:id])
36    
37    if @article.update(article_params)
38      redirect_to @article, notice: "Article updated!"
39    else
40      render :edit, status: :unprocessable_entity
41    end
42  end
43  
44  # DELETE /articles/:id
45  def destroy
46    @article = Article.find(params[:id])
47    @article.destroy
48    redirect_to articles_url, notice: "Article deleted!"
49  end
50  
51  private
52  
53  def article_params
54    params.require(:article).permit(:title, :body, :published)
55  end
56end

1# config/routes.rb
2Rails.application.routes.draw do
3  resources :articles
4end

1# Routes
2resources :articles do
3  resources :comments
4end
5
6# Controller
7class CommentsController < ApplicationController
8  before_action :set_article
9  
10  # GET /articles/:article_id/comments
11  def index
12    @comments = @article.comments
13  end
14  
15  # POST /articles/:article_id/comments
16  def create
17    @comment = @article.comments.build(comment_params)
18    
19    if @comment.save
20      redirect_to @article, notice: "Comment added!"
21    else
22      render "articles/show"
23    end
24  end
25  
26  # DELETE /articles/:article_id/comments/:id
27  def destroy
28    @comment = @article.comments.find(params[:id])
29    @comment.destroy
30    redirect_to @article, notice: "Comment deleted!"
31  end
32  
33  private
34  
35  def set_article
36    @article = Article.find(params[:article_id])
37  end
38  
39  def comment_params
40    params.require(:comment).permit(:body)
41  end
42end

1# Routes
2resources :articles do
3  resources :comments, shallow: true
4end
5
6# Generates:
7# /articles/:article_id/comments     (index, new, create)
8# /comments/:id                      (show, edit, update, destroy)

1# Routes
2resources :articles do
3  member do
4    post :publish
5    post :unpublish
6    get :preview
7  end
8end
9
10# Or single action
11resources :articles do
12  post :publish, on: :member
13end
14
15# Controller
16class ArticlesController < ApplicationController
17  # POST /articles/:id/publish
18  def publish
19    @article = Article.find(params[:id])
20    @article.update(published: true, published_at: Time.current)
21    redirect_to @article, notice: "Article published!"
22  end
23  
24  # GET /articles/:id/preview
25  def preview
26    @article = Article.find(params[:id])
27    render layout: "preview"
28  end
29end

1# Routes
2resources :articles do
3  collection do
4    get :search
5    get :published
6    get :drafts
7    delete :clear_old
8  end
9end
10
11# Controller
12class ArticlesController < ApplicationController
13  # GET /articles/search
14  def search
15    @articles = Article.where("title LIKE ?", "%#{params[:q]}%")
16    render :index
17  end
18  
19  # GET /articles/published
20  def published
21    @articles = Article.where(published: true)
22    render :index
23  end
24  
25  # DELETE /articles/clear_old
26  def clear_old
27    Article.where("created_at < ?", 1.year.ago).destroy_all
28    redirect_to articles_path, notice: "Old articles cleared!"
29  end
30end

1class ArticlesController < ApplicationController
2  def index
3    @articles = Article.all
4    
5    respond_to do |format|
6      format.html # renders index.html.erb
7      format.json { render json: @articles }
8      format.xml { render xml: @articles }
9      format.csv { send_data @articles.to_csv }
10    end
11  end
12  
13  def show
14    @article = Article.find(params[:id])
15    
16    respond_to do |format|
17      format.html
18      format.json { render json: @article }
19      format.pdf do
20        pdf = ArticlePdf.new(@article)
21        send_data pdf.render, filename: "#{@article.slug}.pdf"
22      end
23    end
24  end
25end

1class CommentsController < ApplicationController
2  def create
3    @article = Article.find(params[:article_id])
4    @comment = @article.comments.build(comment_params)
5    
6    if @comment.save
7      respond_to do |format|
8        format.turbo_stream
9        format.html { redirect_to @article }
10      end
11    else
12      render :new
13    end
14  end
15end

1<!-- app/views/comments/create.turbo_stream.erb -->
2<%= turbo_stream.prepend "comments", @comment %>
3<%= turbo_stream.update "comment_form", partial: "comments/form", locals: { comment: Comment.new } %>

1class ArticlesController < ApplicationController
2  rescue_from ActiveRecord::RecordNotFound, with: :not_found
3  rescue_from ActionController::ParameterMissing, with: :bad_request
4  
5  def show
6    @article = Article.find(params[:id])
7  end
8  
9  private
10  
11  def not_found
12    respond_to do |format|
13      format.html { render "errors/not_found", status: :not_found }
14      format.json { render json: { error: "Not found" }, status: :not_found }
15    end
16  end
17  
18  def bad_request(exception)
19    render json: { error: exception.message }, status: :bad_request
20  end
21end

1# Fat controller (bad)
2class ArticlesController < ApplicationController
3  def create
4    @article = Article.new(article_params)
5    @article.user = current_user
6    @article.published_at = Time.current if params[:publish]
7    @article.slug = @article.title.parameterize
8    
9    if @article.save
10      ArticleMailer.new_article(@article).deliver_later
11      AdminNotifier.notify(@article)
12      redirect_to @article
13    else
14      render :new
15    end
16  end
17end
18
19# Skinny controller (good)
20class ArticlesController < ApplicationController
21  def create
22    @article = current_user.articles.build(article_params)
23    
24    if @article.save
25      @article.notify_subscribers
26      redirect_to @article
27    else
28      render :new
29    end
30  end
31end