1 files changed, 65 insertions, 0 deletions
diff --git a/app/services/work_items/related_work_item_links/create_service.rb b/app/services/work_items/related_work_item_links/create_service.rb
new file mode 100644
index 00000000000..6a9ddd5c83d
--- /dev/null
+++ b/app/services/work_items/related_work_item_links/create_service.rb
@@ -0,0 +1,65 @@
+# frozen_string_literal: true
+
+module WorkItems
+  module RelatedWorkItemLinks
+    class CreateService < IssuableLinks::CreateService
+      extend ::Gitlab::Utils::Override
+
+      def execute
+        return error(_('No matching work item found.'), 404) unless can?(current_user, :admin_work_item_link, issuable)
+
+        response = super
+
+        if response[:status] == :success
+          response[:message] = format(
+            _('Successfully linked ID(s): %{item_ids}.'),
+            item_ids: linked_ids(response[:created_references]).to_sentence
+          )
+        end
+
+        response
+      end
+
+      def linkable_issuables(work_items)
+        @linkable_issuables ||= work_items.select { |work_item| can_link_item?(work_item) }
+      end
+
+      def previous_related_issuables
+        @related_issues ||= issuable.related_issues(current_user).to_a
+      end
+
+      private
+
+      def link_class
+        WorkItems::RelatedWorkItemLink
+      end
+
+      def can_link_item?(work_item)
+        return true if can?(current_user, :admin_work_item_link, work_item)
+
+        @errors << format(
+          _("Item with ID: %{id} cannot be added. You don't have permission to perform this action."),
+          id: work_item.id
+        )
+
+        false
+      end
+
+      def linked_ids(created_links)
+        created_links.collect(&:target_id)
+      end
+
+      override :issuables_already_assigned_message
+      def issuables_already_assigned_message
+        _('Work items are already linked')
+      end
+
+      override :issuables_not_found_message
+      def issuables_not_found_message
+        _('No matching work item found. Make sure you are adding a valid ID and you have access to the item.')
+      end
+    end
+  end
+end
+
+WorkItems::RelatedWorkItemLinks::CreateService.prepend_mod_with('WorkItems::RelatedWorkItemLinks::CreateService')