mongodb/mongoid · error · Mongoid::Errors::ReadonlyDocument

Attempted to persist a readonly document of class '%{klass}'

Error message

Attempted to persist a readonly document of class '%{klass}'.

What it means

Error "Attempted to persist a readonly document of class '%{klass}'." thrown in mongodb/mongoid.

Source

Thrown at lib/mongoid/persistable/creatable.rb:121

        remember_storage_options!
        flag_descendants_persisted
        true
      end

      # Prepare the insert for execution. Validates and runs callbacks, etc.
      #
      # @api private
      #
      # @example Prepare for insertion.
      #   document.prepare_insert do
      #     collection.insert(as_document)
      #   end
      #
      # @param [ Hash ] options The options.
      #
      # @return [ Document ] The document.
      def prepare_insert(options = {})
        raise Errors::ReadonlyDocument.new(self.class) if readonly? && !Mongoid.legacy_readonly
        return self if performing_validations?(options) &&
                       invalid?(options[:context] || :create)

        ensure_client_compatibility!
        run_callbacks(:commit, with_children: true, skip_if: -> { in_transaction? }) do
          run_callbacks(:save, with_children: false) do
            run_callbacks(:create, with_children: false) do
              run_callbacks(:persist_parent, with_children: false) do
                _mongoid_run_child_callbacks(:save) do
                  _mongoid_run_child_callbacks(:create) do
                    result = yield(self)
                    if !result.is_a?(Document) || result.errors.empty?
                      post_process_insert
                      post_process_persist(result, options)
                    end
                  end
                end
              end

View on GitHub (pinned to 0da0e23d71)

When it happens

Trigger: Thrown at lib/mongoid/persistable/creatable.rb:121 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of mongodb/mongoid@0da0e23d71 (2026-08-23). Data as JSON: /api/errors/eeb3e30ff593241e. Report an issue: GitHub.