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

Document(s) not found for class %{klass} with id(s) %{missin

Error message

Document(s) not found for class %{klass} with id(s) %{missing}.

What it means

Error "Document(s) not found for class %{klass} with id(s) %{missing}." thrown in mongodb/mongoid.

Source

Thrown at lib/mongoid/association/nested/many.rb:193

        #   builder.update_nested_relation(parent, id, attrs)
        #
        # @param [ Document ] parent The parent document.
        # @param [ String | BSON::ObjectId ] id of the related document.
        # @param [ Hash ] attrs The single document attributes to process.
        def update_nested_relation(parent, id, attrs)
          first = existing.first
          converted = first ? convert_id(first.class, id) : id

          if existing.where(_id: converted).exists?
            # document exists in association
            doc = existing.find(converted)
            if destroyable?(attrs)
              destroy(parent, existing, doc)
            else
              update_document(doc, attrs)
            end
          elsif association.embedded?
            raise Errors::DocumentNotFound.new(association.klass, id)
          elsif association.is_a?(Association::Referenced::HasAndBelongsToMany) || Mongoid.allow_reparenting_via_nested_attributes?
            unless destroyable?(attrs)
              Mongoid::Warnings.warn_reparenting_via_nested_attributes if Mongoid.allow_reparenting_via_nested_attributes?

              # push existing document to association
              doc = association.klass.unscoped.find(converted)
              # find returns nil instead of raising when
              # Mongoid.raise_not_found_error is false; a missing document
              # must still be an error here, consistent with the other
              # not-found branches.
              raise Errors::DocumentNotFound.new(association.klass, id) if doc.nil?

              update_document(doc, attrs)
              existing.push(doc)
            end
          else
            raise Errors::DocumentNotFound.new(association.klass, { _id: id, association.foreign_key => parent.id })
          end

View on GitHub (pinned to 0da0e23d71)

When it happens

Trigger: Thrown at lib/mongoid/association/nested/many.rb:193 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/e90461ff7fe7f254. Report an issue: GitHub.