From 60ec1d625091539b9966ddd65feed1b0422a1787 Mon Sep 17 00:00:00 2001
From: Carl Chenet <chaica@ohmytux.com>
Date: Tue, 16 May 2017 19:48:01 +0200
Subject: [PATCH] users: do dumb caching of these big user trees

---
 app/controllers/users_controller.rb | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/app/controllers/users_controller.rb b/app/controllers/users_controller.rb
index 4371d25..4bcf869 100644
--- a/app/controllers/users_controller.rb
+++ b/app/controllers/users_controller.rb
@@ -16,11 +16,16 @@ class UsersController < ApplicationController
   def tree
     @title = I18n.t 'controllers.users_controller.usertitle'
 
+    newest_user = User.last.id
+
     if params[:by].to_s == "karma"
-      @users = User.order("karma DESC, id ASC").to_a
-      @user_count = @users.length
-      @title << " By Karma"
-      render :action => "list"
+      render :text => Rails.cache.fetch("users_by_karma_#{newest_user}",
+      :expires_in => (60 * 60 * 24)) {
+        @users = User.order("karma DESC, id ASC").to_a
+        @user_count = @users.length
+        @title << " By Karma"
+        render_to_string :action => "list"
+      }
     elsif params[:moderators]
       @users = User.where("is_admin = ? OR is_moderator = ?", true, true).
         order("id ASC").to_a
@@ -28,10 +33,14 @@ class UsersController < ApplicationController
       @title = "Moderators and Administrators"
       render :action => "list"
     else
-      users = User.order("id DESC").to_a
-      @user_count = users.length
-      @users_by_parent = users.group_by(&:invited_by_user_id)
-      @newest = User.order("id DESC").limit(10)
+      render :text => Rails.cache.fetch("users_tree_#{newest_user}",
+      :expires_in => (60 * 60 * 24)) {
+        users = User.order("id DESC").to_a
+        @user_count = users.length
+        @users_by_parent = users.group_by(&:invited_by_user_id)
+        @newest = User.order("id DESC").limit(10)
+        render_to_string :action => "tree"
+      }
     end
   end