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,
      sample_rate: span.sample_rate,
      outcome: keyword_field(span.outcome)
    }
  }
end

def initialize(config)
  super
  @context_serializer = ContextSerializer.new(config)
end

def join_type(span)
  combined = [span.type, span.subtype, span.action]
  combined.compact!
  combined.join '.'
end