6 files changed, 56 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/group_child_entity.rb b/app/serializers/group_child_entity.rb
index 37240bfb0b1..aca4e4ca488 100644
--- a/app/serializers/group_child_entity.rb
+++ b/app/serializers/group_child_entity.rb
@@ -1,6 +1,7 @@
 class GroupChildEntity < Grape::Entity
   include ActionView::Helpers::NumberHelper
   include RequestAwareEntity
+  include MarkupHelper
 
   expose :id, :name, :description, :visibility, :full_name,
          :created_at, :updated_at, :avatar_url
@@ -59,6 +60,10 @@ class GroupChildEntity < Grape::Entity
     number_with_delimiter(instance.member_count)
   end
 
+  expose :markdown_description do |instance|
+    markdown_description
+  end
+
   private
 
   def membership
@@ -74,4 +79,8 @@ class GroupChildEntity < Grape::Entity
   def type
     object.class.name.downcase
   end
+
+  def markdown_description
+    markdown_field(object, :description)
+  end
 end
diff --git a/app/serializers/job_entity.rb b/app/serializers/job_entity.rb
index 72e56a2c77f..523b522d449 100644
--- a/app/serializers/job_entity.rb
+++ b/app/serializers/job_entity.rb
@@ -4,6 +4,8 @@ class JobEntity < Grape::Entity
   expose :id
   expose :name
 
+  expose :started?, as: :started
+
   expose :build_path do |build|
     build.target_url || path_to(:namespace_project_job, build)
   end
diff --git a/app/serializers/merge_request_basic_entity.rb b/app/serializers/merge_request_basic_entity.rb
index d54a6516aed..e4aec977f01 100644
--- a/app/serializers/merge_request_basic_entity.rb
+++ b/app/serializers/merge_request_basic_entity.rb
@@ -4,4 +4,5 @@ class MergeRequestBasicEntity < IssuableSidebarEntity
   expose :merge_error
   expose :state
   expose :source_branch_exists?, as: :source_branch_exists
+  expose :rebase_in_progress?, as: :rebase_in_progress
 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..48cd2317f46 100644
--- a/app/serializers/merge_request_widget_entity.rb
+++ b/app/serializers/merge_request_widget_entity.rb
@@ -17,9 +17,21 @@ 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
+
+  expose :rebase_commit_sha
+  expose :rebase_in_progress?, as: :rebase_in_progress
+
+  expose :can_push_to_source_branch do |merge_request|
+    presenter(merge_request).can_push_to_source_branch?
+  end
+  expose :rebase_path do |merge_request|
+    presenter(merge_request).rebase_path
+  end
 
   # User entities
   expose :merge_user, using: UserEntity
@@ -178,4 +190,27 @@ 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