class ElasticAPM::Transport::Serializers::SpanSerializer

def build(span)
  {
    span: {
      id: span.id,
      transaction_id: span.transaction.id,
      parent_id: span.parent_id,
      name: keyword_field(span.name),
      type: join_type(span),
      duration: ms(span.duration),
      context: context_serializer.build(span.context),
      stacktrace: span.stacktrace.to_a,
      timestamp: span.timestamp,
      trace_id: span.trace_id
    }
  }
end