add performance artifacts to the merge request widget

ee/app/models/ee/ci/build.rb

@@ -9,6 +9,7 @@ module EE
 
       included do
         scope :codequality, ->() { where(name: %w[codequality codeclimate]) }
+        scope :performance, ->() { where(name: %w[performance deploy]) }
         scope :sast, ->() { where(name: 'sast') }
 
         after_save :stick_build_if_status_changed
@@ -30,6 +31,11 @@ module EE
           artifacts_metadata?
       end
 
+      def has_performance_json?
+        options.dig(:artifacts, :paths) == ['performance.json'] &&
+          artifacts_metadata?
+      end
+
       def has_sast_json?
         options.dig(:artifacts, :paths) == ['gl-sast-report.json'] &&
           artifacts_metadata?

ee/app/models/ee/ci/pipeline.rb

@@ -17,6 +17,10 @@ module EE
         artifacts.codequality.find(&:has_codeclimate_json?)
       end
 
+      def performance_artifact
+        artifacts.performance.find(&:has_performance_json?)
+      end
+
       def sast_artifact
         artifacts.sast.find(&:has_sast_json?)
       end

ee/app/models/ee/merge_request.rb

@@ -11,6 +11,8 @@ module EE
 
       delegate :codeclimate_artifact, to: :head_pipeline, prefix: :head, allow_nil: true
       delegate :codeclimate_artifact, to: :base_pipeline, prefix: :base, allow_nil: true
+      delegate :performance_artifact, to: :head_pipeline, prefix: :head, allow_nil: true
+      delegate :performance_artifact, to: :base_pipeline, prefix: :base, allow_nil: true
       delegate :sast_artifact, to: :head_pipeline, allow_nil: true
       delegate :sha, to: :head_pipeline, prefix: :head_pipeline, allow_nil: true
       delegate :sha, to: :base_pipeline, prefix: :base_pipeline, allow_nil: true
@@ -44,6 +46,11 @@ module EE
          base_codeclimate_artifact&.success?)
     end
 
+    def has_performance_data?
+      !!(head_performance_artifact&.success? &&
+         base_performance_artifact&.success?)
+    end
+
     def has_sast_data?
       sast_artifact&.success?
     end

ee/app/serializers/ee/merge_request_entity.rb

@@ -25,6 +25,20 @@ module EE
         end
       end
 
+      expose :performance, if: -> (mr, _) { mr.has_performance_data? } do
+        expose :head_path, if: -> (mr, _) { can?(current_user, :read_build, mr.head_performance_artifact) } do |merge_request|
+          raw_project_build_artifacts_url(merge_request.source_project,
+                                          merge_request.head_performance_artifact,
+                                          path: 'performance.json')
+        end
+
+        expose :base_path, if: -> (mr, _) { can?(current_user, :read_build, mr.base_performance_artifact) } do |merge_request|
+          raw_project_build_artifacts_url(merge_request.target_project,
+                                          merge_request.base_performance_artifact,
+                                          path: 'performance.json')
+        end
+      end
+
       expose :sast, if: -> (mr, _) { expose_sast_data?(mr, current_user) } do
         expose :path do |merge_request|
           raw_project_build_artifacts_url(merge_request.source_project,