Merge branch 'fix/invalidate-builds-badge-cache' into 'master'

Invalidate cache for builds badge

This fixes cache issue with badges (we should not cache badge images).

Closes #13982

See merge request !3086

CHANGELOG

 Please view this file on the master branch, on stable branches it's out of date.
 
+v 8.6.0 (unreleased)
+  - Contributions to forked projects are included in calendar
+  - Improve the formatting for the user page bio (Connor Shea)
+  - Fix issue when pushing to projects ending in .wiki
+  - Fix avatar stretching by providing a cropping feature (Johann Pardanaud)
+  - Don't load all of GitLab in mail_room
+  - Strip leading and trailing spaces in URL validator (evuez)
+  - Return empty array instead of 404 when commit has no statuses in commit status API
+  - Update documentation to reflect Guest role not being enforced on internal projects
+  - Allow search for logged out users
+  - Don't show Issues/MRs from archived projects in Groups view
+  - Increase the notes polling timeout over time (Roberto Dip)
+
+v 8.5.4 (unreleased)
+  - Do not cache requests for badges (including builds badge)
+
 v 8.5.3
   - Flush repository caches before renaming projects
 

app/controllers/projects/badges_controller.rb

 class Projects::BadgesController < Projects::ApplicationController
+  before_action :set_no_cache
+
   def build
     respond_to do |format|
       format.html { render_404 }
@@ -8,4 +10,15 @@ class Projects::BadgesController < Projects::ApplicationController
       end
     end
   end
+
+  private
+
+  def set_no_cache
+    expires_now
+
+    # Add some deprecated headers for older agents
+    #
+    response.headers['Pragma'] = 'no-cache'
+    response.headers['Expires'] = 'Fri, 01 Jan 1990 00:00:00 GMT'
+  end
 end

features/project/badges/build.feature

@@ -20,3 +20,8 @@ Feature: Project Badges Build
     And project has another build that is running
     When I display builds badge for a master branch
     Then I should see a build running badge
+
+  Scenario: I want to see a fresh badge on each request
+    Given recent build is successful
+    When I display builds badge for a master branch
+    Then I should see a badge that has not been cached

features/steps/project/badges/build.rb

@@ -20,6 +20,10 @@ class Spinach::Features::ProjectBadgesBuild < Spinach::FeatureSteps
     expect_badge('running')
   end
 
+  step 'I should see a badge that has not been cached' do
+    expect(page.response_headers).to include('Cache-Control' => 'no-cache')
+  end
+
   def expect_badge(status)
     svg = Nokogiri::XML.parse(page.body)
     expect(page.response_headers).to include('Content-Type' => 'image/svg+xml')