Add markdown cache columns to the database, but don't use them yet

This commit adds a number of _html columns and, with the exception of Note,
starts updating them whenever the content of their partner fields changes.

Note has a collision with the note_html attr_accessor; that will be fixed later

A background worker for clearing these cache columns is also introduced - use
`rake cache:clear` to set it off. You can clear the database or Redis caches
separately by running `rake cache:clear:db` or `rake cache:clear:redis`,
respectively.

1 files changed, 2 insertions, 10 deletions

diff --git a/spec/services/system_note_service_spec.rb b/spec/services/system_note_service_spec.rb
index d1a47ea9b6f..304d4e62396 100644
--- a/spec/services/system_note_service_spec.rb
+++ b/spec/services/system_note_service_spec.rb
@@ -531,12 +531,12 @@ describe SystemNoteService, services: true do
   include JiraServiceHelper
 
   describe 'JIRA integration' do
-    let(:project)    { create(:project) }
+    let(:project)    { create(:jira_project) }
     let(:author)     { create(:user) }
     let(:issue)      { create(:issue, project: project) }
     let(:mergereq)   { create(:merge_request, :simple, target_project: project, source_project: project) }
     let(:jira_issue) { ExternalIssue.new("JIRA-1", project)}
-    let(:jira_tracker) { project.create_jira_service if project.jira_service.nil? }
+    let(:jira_tracker) { project.jira_service }
     let(:commit)     { project.commit }
 
     context 'in JIRA issue tracker' do
@@ -545,10 +545,6 @@ describe SystemNoteService, services: true do
         WebMock.stub_request(:post, jira_api_comment_url)
       end
 
-      after do
-        jira_tracker.destroy!
-      end
-
       describe "new reference" do
         before do
           WebMock.stub_request(:get, jira_api_comment_url).to_return(body: jira_issue_comments)
@@ -578,10 +574,6 @@ describe SystemNoteService, services: true do
           WebMock.stub_request(:get, jira_api_comment_url).to_return(body: jira_issue_comments)
         end
 
-        after do
-          jira_tracker.destroy!
-        end
-
         subject { described_class.cross_reference(jira_issue, issue, author) }
 
         it { is_expected.to eq(jira_status_message) }