Add Bullet gem for dev & fix N+1 queries issues for core index actions

app/controllers/contestants_controller.rb

@@ -12,7 +12,7 @@ class ContestantsController < ApplicationController
   def index
     authorize @contest
 
-    @contestants = @contest.contestants.sort_by { |contestant| contestant.name }
+    @contestants = @contest.contestants.includes([ :completions, :offline ]).sort_by { |contestant| contestant.name }
     filter_contestants_per_category
   end
 

app/controllers/contests_controller.rb

@@ -10,7 +10,7 @@ class ContestsController < ApplicationController
   def index
     authorize :contest
 
-    @contests = current_user.contests
+    @contests = current_user.contests.includes([ :contestants, puzzles: [ :image_attachment ] ])
     @title = I18n.t("contests.index.title", username: current_user.username)
   end
 

app/controllers/puzzles_controller.rb

@@ -6,7 +6,7 @@ class PuzzlesController < ApplicationController
     authorize @contest
 
     @title = @contest.name
-    @puzzles = @contest.puzzles.order(:id)
+    @puzzles = @contest.puzzles.includes([ :image_attachment ]).order(:id)
   end
 
   def edit

app/controllers/users_controller.rb

@@ -7,7 +7,7 @@ class UsersController < ApplicationController
     authorize :user
 
     @title = t("users.index.title")
-    @users = User.all
+    @users = User.all.includes(contests: [ :contestants, :puzzles ])
   end
 
   def edit