diff --git a/app/controllers/competitions/competition_modules_controller.rb b/app/controllers/competitions/competition_modules_controller.rb
index da9873c43..c4692af70 100644
--- a/app/controllers/competitions/competition_modules_controller.rb
+++ b/app/controllers/competitions/competition_modules_controller.rb
@@ -15,7 +15,17 @@ class Competitions::CompetitionModulesController < Competitions::BaseController
     md = current_module.competition_module_md_content || current_module.build_competition_module_md_content
     md.name    = params[:md_name]
     md.content = params[:md_content]
-    md.save!
+
+    ActiveRecord::Base.transaction do
+      md.save!
+
+      attachment_ids = Array.wrap(params[:attachment_ids]).map(&:to_i)
+      old_attachment_ids = md.attachments.pluck(:id)
+
+      destroy_ids = old_attachment_ids - attachment_ids
+      md.attachments.where(id: destroy_ids).delete_all
+      Attachment.where(id: attachment_ids - old_attachment_ids).update_all(container: md)
+    end
 
     render_ok
   end
diff --git a/app/models/searchable/dependents/user.rb b/app/models/searchable/dependents/user.rb
index 103131ed6..f6dcaa430 100644
--- a/app/models/searchable/dependents/user.rb
+++ b/app/models/searchable/dependents/user.rb
@@ -10,13 +10,13 @@ module Searchable::Dependents::User
   def check_searchable_dependents
     if firstname_previously_changed? || lastname_previously_changed? || user_extension.school_id_previously_changed?
       # reindex shixun
-      created_shixuns.each{ |shixun| shixun.reindex }
+      created_shixuns.each(&:reindex)
 
       # reindex course
       manage_courses.each(&:reindex)
 
       # reindex subject
-      created_subjects.each { |subject| subject.reindex }
+      created_subjects.each(&:reindex)
     end
   end
 end
\ No newline at end of file
diff --git a/app/views/competitions/competition_modules/show.json.jbuilder b/app/views/competitions/competition_modules/show.json.jbuilder
index d47742cf0..69cdcc544 100644
--- a/app/views/competitions/competition_modules/show.json.jbuilder
+++ b/app/views/competitions/competition_modules/show.json.jbuilder
@@ -5,4 +5,7 @@ if md.present?
   json.md_name md.name
   json.md_content md.content
   json.created_at md.created_at.strftime('%Y-%m-%d %H:%M:%S')
+  json.attachments do
+    json.array! md.attachments, partial: 'attachments/attachment_simple', as: :attachment
+  end
 end
\ No newline at end of file