Fixed pagination of web hook logs

For reasons unknown, the logs of a web hook were paginated in memory.
This would result in the "Edit" page of a web hook timing out once it
has more than a few thousand log entries.

This commit makes the following changes:

1. We use LIMIT/OFFSET to paginate the data, instead of doing this in
   memory.

2. We limit the logs to the last two days, just like the documentation
   says (instead of retrieving everything).

3. We change the indexes on "web_hook_logs" so the query to get the data
   can perform a backwards index scan, without the need for a Filter.

These changes combined ensure that Projects::HooksController#edit no
longer times out.

3 files changed, 7 insertions, 4 deletions

diff --git a/app/controllers/admin/hooks_controller.rb b/app/controllers/admin/hooks_controller.rb
index fb788c47ef1..6944857bd33 100644
--- a/app/controllers/admin/hooks_controller.rb
+++ b/app/controllers/admin/hooks_controller.rb
@@ -52,8 +52,7 @@ class Admin::HooksController < Admin::ApplicationController
   end
 
   def hook_logs
-    @hook_logs ||=
-      Kaminari.paginate_array(hook.web_hook_logs.order(created_at: :desc)).page(params[:page])
+    @hook_logs ||= hook.web_hook_logs.recent.page(params[:page])
   end
 
   def hook_params
diff --git a/app/controllers/projects/hooks_controller.rb b/app/controllers/projects/hooks_controller.rb
index dd7aa1a67b9..6800d742b0a 100644
--- a/app/controllers/projects/hooks_controller.rb
+++ b/app/controllers/projects/hooks_controller.rb
@@ -58,8 +58,7 @@ class Projects::HooksController < Projects::ApplicationController
   end
 
   def hook_logs
-    @hook_logs ||=
-      Kaminari.paginate_array(hook.web_hook_logs.order(created_at: :desc)).page(params[:page])
+    @hook_logs ||= hook.web_hook_logs.recent.page(params[:page])
   end
 
   def hook_params
diff --git a/app/models/hooks/web_hook_log.rb b/app/models/hooks/web_hook_log.rb
index e72c125fb69..59a1f2aed69 100644
--- a/app/models/hooks/web_hook_log.rb
+++ b/app/models/hooks/web_hook_log.rb
@@ -7,6 +7,11 @@ class WebHookLog < ActiveRecord::Base
 
   validates :web_hook, presence: true
 
+  def self.recent
+    where('created_at >= ?', 2.days.ago.beginning_of_day)
+      .order(created_at: :desc)
+  end
+
   def success?
     response_status =~ /^2/
   end