Avoid open/close transaction in each gon helper callproper-default-issue-tracker

require 'benchmark/ips'

Project.first # To load database things
GitlabIssueTrackerService.first # To load database things

Benchmark.ips do |x|
  x.config(:time => 5, :warmup => 2)

  x.report("current") do
    Project.new.default_issue_tracker.to_param
  end

  x.report("") do
    Project.default_issue_tracker_service_name
  end

  x.compare!
end


Calculating -------------------------------------
             current     3.000  i/100ms
                        22.466k i/100ms
-------------------------------------------------
             current     39.875  (±15.0%) i/s -    192.000 
                          1.444M (±14.8%) i/s -      6.605M

Comparison:
                    :  1443612.8 i/s
             current:       39.9 i/s - 36203.16x slower

1 files changed, 13 insertions, 1 deletions

diff --git a/app/models/project.rb b/app/models/project.rb
index ca3bc04e2dd..d9d572e81c3 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -372,6 +372,14 @@ class Project < ActiveRecord::Base
     def remove_gitlab_exports!
       Gitlab::Popen.popen(%W(find #{Gitlab::ImportExport.storage_path} -not -path #{Gitlab::ImportExport.storage_path} -mmin +1440 -delete))
     end
+
+    def default_issue_tracker_service
+      :gitlab_issue_tracker_service
+    end
+
+    def default_issue_tracker_service_name
+      reflect_on_association(default_issue_tracker_service).klass::NAME
+    end
   end
 
   def team
@@ -583,8 +591,12 @@ class Project < ActiveRecord::Base
     get_issue(issue_id)
   end
 
+  def default_issue_tracker_service
+    self.class.default_issue_tracker_service
+  end
+
   def default_issue_tracker
-    gitlab_issue_tracker_service || create_gitlab_issue_tracker_service
+    association(default_issue_tracker_service).target || association(default_issue_tracker_service).create
   end
 
   def issues_tracker