add /comments/latest route

This page will be useful for moderators to retrieve latest comments.

The limit is based on current date to limit number of comments retrieved
from the database. Only comments from the last 7 days will be available.

As it's the first page to index all comments with criteria only made on
created_at property, I added an index to the comments sql table.

As LinuxFr has between 1500 to 2000 comments each 15 days, I've decided
to paginate to 50 comments. As the number of comments in the atom feed is
linked to this pagination setting, I wanted it to be big enough so RSS readers
can take all comments with around 4 requests by day.

Author: Trim

app/assets/stylesheets/parts/content.scss

@@ -1,6 +1,7 @@
 /* contenu du site (hors commentaire) */
 article,
 ul.threads > li.comment,
+ul.comments_list > li.comment,
 .markdown_cheatsheet,
 #contents > form,
 form#new_post,
@@ -30,6 +31,10 @@ body#wiki_pages-changes #contents {
   font-size: 1em;
 }
 
+#contents > ul.comments_list {
+  padding: 0;
+}
+
 article {
   position: relative;
   header {

app/controllers/comments_controller.rb

@@ -1,8 +1,8 @@
 # encoding: UTF-8
 class CommentsController < ApplicationController
-  before_action :authenticate_account!, except: [:index, :show]
-  before_action :find_node, except: [:templeet]
-  before_action :find_comment, except: [:index, :new, :answer, :create, :templeet]
+  before_action :authenticate_account!, except: [:index, :show, :latest]
+  before_action :find_node, except: [:templeet, :latest]
+  before_action :find_comment, except: [:index, :new, :answer, :create, :templeet, :latest]
 
   def index
     @comments = @node.comments.published.order('id DESC')
@@ -12,6 +12,16 @@ def index
     end
   end
 
+  def latest
+    @comments = Comment.latest.
+      page(params[:page]).
+      order(created_at: :desc)
+    respond_to do |wants|
+      wants.html
+      wants.atom
+    end
+  end
+
   def show
     enforce_view_permission(@comment)
   end

app/models/comment.rb

@@ -39,6 +39,11 @@ class Comment < ActiveRecord::Base
       limit(12).
       select([:id, :node_id, :title])
   }
+  scope :latest, -> {
+    where(["created_at >= ?", Date.current - 7.day])
+  }
+
+  paginates_per 50
 
   validates :title,     presence: { message: "Le titre est obligatoire" },
                         length: { maximum: 100, message: "Le titre est trop long" }

app/views/comments/latest.atom.builder

@@ -0,0 +1,25 @@
+atom_feed(:root_url => comments_latest_url) do |feed|
+  feed.title("LinuxFr.org : les derniers commentaires")
+  feed.updated(@comments.first.try :created_at)
+  feed.icon("/favicon.png")
+
+  @comments.each do |comment|
+    feed.entry(comment, :url => "#{url_for_content comment.node.content}#comment-#{comment.id}") do |entry|
+      in_response_to = content_tag(:p,
+        content_tag(:em,
+          "En réponse #{translate_to_content_type comment.content_type} #{link_to comment.node.content.title, path_for_content(comment.node.content)}.".html_safe
+        )
+      )
+      if comment.deleted?
+        entry.title("Commentaire supprimé")
+        entry.content("#{content_tag(:p, "Commentaire supprimé")} #{in_response_to}", :type => 'html')
+      else
+        entry.title(comment.title)
+        entry.content("#{comment.body} #{in_response_to}", :type => 'html')
+      end
+      entry.author do |author|
+        author.name(comment.user_name)
+      end
+    end
+  end
+end

app/views/comments/latest.html.haml

@@ -0,0 +1,15 @@
+= h1 "Les derniers commentaires"
+- feed "Flux Atom des derniers commentaires"
+%nav.toolbox
+  .follow_feed
+    = link_to "Flux Atom des derniers commentaires", "latest.atom"
+  -# order is not managed, but order_navbar is required due to float property on follow_feed div
+  .order_navbar
+     
+%main#contents(role="main")
+  %ul.comments_list
+    - @comments.each do |comment|
+      %li.comment(id="comment-#{comment.id}")
+        = render comment
+%nav.toolbox
+  = paginate(@comments, inner_window:10)

app/views/moderation/news/index.html.haml

@@ -28,6 +28,9 @@
 %h2
   = link_to "Étiquettes publiques", moderation_tags_path
 
+%h2
+  = link_to "Derniers commentaires", comments_latest_path
+
 %h2
   = link_to "Sondages", moderation_polls_path
 - if @polls.empty?

config/routes.rb

@@ -58,6 +58,7 @@
   # Nodes
   get "/tableau-de-bord" => "dashboard#index", as: :dashboard
   get "/tableau-de-bord/reponses" => "dashboard#answers"
+  get "/comments/latest" => "comments#latest"
   get "/comments/:id(,:d)(.html)" => "comments#templeet"
   resources :nodes, only: [] do
     resources :comments do

db/migrate/20210913191843_add_index_on_created_at_to_comments.rb

@@ -0,0 +1,5 @@
+class AddIndexOnCreatedAtToComments < ActiveRecord::Migration[5.2]
+  def change
+    add_index :comments, [:created_at], order: {created_at: :desc}
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2021_01_31_231806) do
+ActiveRecord::Schema.define(version: 2021_09_13_191843) do
 
   create_table "accounts", id: :integer, options: "ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci", force: :cascade do |t|
     t.integer "user_id"
@@ -93,6 +93,7 @@
     t.text "wiki_body", limit: 16777215
     t.datetime "created_at"
     t.datetime "updated_at"
+    t.index ["created_at"], name: "index_comments_on_created_at"
     t.index ["node_id"], name: "index_comments_on_node_id"
     t.index ["state", "created_at"], name: "index_comments_on_state_and_created_at"
     t.index ["state", "materialized_path"], name: "index_comments_on_state_and_materialized_path", length: { materialized_path: 120 }