1 files changed, 19 insertions, 0 deletions
diff --git a/lib/api/helpers.rb b/lib/api/helpers.rb
index b56fd2388b3..84980864151 100644
--- a/lib/api/helpers.rb
+++ b/lib/api/helpers.rb
@@ -11,6 +11,25 @@ module API
       declared(params, options).to_h.symbolize_keys
     end
 
+    def check_unmodified_since!(last_modified)
+      if_unmodified_since = Time.parse(headers['If-Unmodified-Since']) rescue nil
+
+      if if_unmodified_since && last_modified && last_modified > if_unmodified_since
+        render_api_error!('412 Precondition Failed', 412)
+      end
+    end
+
+    def destroy_conditionally!(resource, last_update_field: :updated_at)
+      check_unmodified_since!(resource.public_send(last_update_field))
+
+      status 204
+      if block_given?
+        yield resource
+      else
+        resource.destroy
+      end
+    end
+
     def current_user
       return @current_user if defined?(@current_user)