1 files changed, 21 insertions, 0 deletions
diff --git a/app/validators/array_members_validator.rb b/app/validators/array_members_validator.rb
new file mode 100644
index 00000000000..c5d3d25b4d9
--- /dev/null
+++ b/app/validators/array_members_validator.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+# ArrayMembersValidator
+#
+# Custom validator that checks if validated
+# attribute contains non empty array, which every
+# element is an instances of :member_class
+#
+# Example:
+#
+#   class Config::Root < ActiveRecord::Base
+#     validates :nodes, member_class: Config::Node
+#   end
+#
+class ArrayMembersValidator < ActiveModel::EachValidator
+  def validate_each(record, attribute, value)
+    if !value.is_a?(Array) || value.empty? || value.any? { |child| !child.instance_of?(options[:member_class]) }
+      record.errors.add(attribute, _("should be an array of %{object_name} objects") % { object_name: options.fetch(:object_name, attribute) })
+    end
+  end
+end