Merge branch 'master' into 22643-manual-job-page

* master: (200 commits)
  Fix issue boards scroll config.
  Added multi editor setting on the profile preferences page
  fix missing import of timeWeek which would cause errors in prometheus graphs with deployments
  Remove downcase from special path helper
  Rename db:seed_fu-{pg,mysql} to gitlab:setup-{pg,mysql}
  Fix error when viewing diffs without blobs
  Moves prettier to dev dependency
  Eager load event target authors whenever possible
  Do not run ee_compat_check on security branches
  Include integration tests in CE/EE testing documentation
  41054-Disallow creation of new Kubernetes integrations
  Resolve "Resizable file list and commit panel"
  Make tooltip placement bottom by default as per design guidelines
  Fix groups list icon, timestamp alignment and row height
  Avoid leaving a push event empty if payload cannot be created
  Move git operations for UpdateRemoteMirrorService into Gitlab::Git
  Move delete_remote_branches from Gitlab::Shell to Gitlab::Git::Repository
  Move push_remote_branches from Gitlab::Shell to Gitlab::Git::Repository
  Update Kubernetes service documentation
  fix issue #37843
  ...

3 files changed, 34 insertions, 7 deletions

diff --git a/app/serializers/event_entity.rb b/app/serializers/event_entity.rb
deleted file mode 100644
index 935d67a4f37..00000000000
--- a/app/serializers/event_entity.rb
+++ /dev/null
@@ -1,4 +0,0 @@
-class EventEntity < Grape::Entity
-  expose :author, using: UserEntity
-  expose :updated_at
-end
diff --git a/app/serializers/merge_request_metrics_entity.rb b/app/serializers/merge_request_metrics_entity.rb
new file mode 100644
index 00000000000..3548107ac16
--- /dev/null
+++ b/app/serializers/merge_request_metrics_entity.rb
@@ -0,0 +1,6 @@
+class MergeRequestMetricsEntity < Grape::Entity
+  expose :latest_closed_at, as: :closed_at
+  expose :merged_at
+  expose :latest_closed_by, as: :closed_by, using: UserEntity
+  expose :merged_by, using: UserEntity
+end
diff --git a/app/serializers/merge_request_widget_entity.rb b/app/serializers/merge_request_widget_entity.rb
index f8e59b2ffd7..e905e6876c2 100644
--- a/app/serializers/merge_request_widget_entity.rb
+++ b/app/serializers/merge_request_widget_entity.rb
@@ -17,9 +17,11 @@ class MergeRequestWidgetEntity < IssuableEntity
     merge_request.project.merge_requests_ff_only_enabled
   end
 
-  # Events
-  expose :merge_event, using: EventEntity
-  expose :closed_event, using: EventEntity
+  expose :metrics do |merge_request|
+    metrics = build_metrics(merge_request)
+
+    MergeRequestMetricsEntity.new(metrics).as_json
+  end
 
   # User entities
   expose :merge_user, using: UserEntity
@@ -178,4 +180,27 @@ class MergeRequestWidgetEntity < IssuableEntity
     @presenters ||= {}
     @presenters[merge_request] ||= MergeRequestPresenter.new(merge_request, current_user: current_user)
   end
+
+  # Once SchedulePopulateMergeRequestMetricsWithEventsData fully runs,
+  # we can remove this method and just serialize MergeRequest#metrics
+  # instead. See https://gitlab.com/gitlab-org/gitlab-ce/issues/41587
+  def build_metrics(merge_request)
+    # There's no need to query and serialize metrics data for merge requests that are not
+    # merged or closed.
+    return unless merge_request.merged? || merge_request.closed?
+    return merge_request.metrics if merge_request.merged? && merge_request.metrics&.merged_by_id
+    return merge_request.metrics if merge_request.closed? && merge_request.metrics&.latest_closed_by_id
+
+    build_metrics_from_events(merge_request)
+  end
+
+  def build_metrics_from_events(merge_request)
+    closed_event = merge_request.closed_event
+    merge_event = merge_request.merge_event
+
+    MergeRequest::Metrics.new(latest_closed_at: closed_event&.updated_at,
+                              latest_closed_by: closed_event&.author,
+                              merged_at: merge_event&.updated_at,
+                              merged_by: merge_event&.author)
+  end
 end