Function instrumentFetchRequest

packages/core/src/fetch.ts:71–164

(
  handlerData: HandlerDataFetch,
  shouldCreateSpan: (url: string) => boolean,
  shouldAttachHeaders: (url: string) => boolean,
  spans: Record<string, Span>,
  spanOriginOrOptions?: SpanOrigin | InstrumentFetchRequestOptions,
)

 * @returns Span if a span was created, otherwise void.
 */
export function instrumentFetchRequest(
  handlerData: HandlerDataFetch,
  shouldCreateSpan: (url: string) => boolean,
  shouldAttachHeaders: (url: string) => boolean,
  spans: Record<string, Span>,
  spanOriginOrOptions?: SpanOrigin | InstrumentFetchRequestOptions,
): Span | undefined {
  if (!handlerData.fetchData) {
    return undefined;
  }

  const { method, url } = handlerData.fetchData;

  const shouldCreateSpanResult = hasSpansEnabled() && shouldCreateSpan(url);

  if (handlerData.endTimestamp) {
    const spanId = handlerData.fetchData.__span;
    if (!spanId) return;

    const span = spans[spanId];

    if (span) {
      // Only end the span and call hooks if we're actually recording
      if (shouldCreateSpanResult) {
        endSpan(span, handlerData);
        _callOnRequestSpanEnd(span, handlerData, spanOriginOrOptions);
      }

      // eslint-disable-next-line @typescript-eslint/no-dynamic-delete
      delete spans[spanId];
    }

    return undefined;
  }

  // Backwards-compatible with the old signature. Needed to introduce the combined optional parameter
  // to avoid API breakage for anyone calling this function with the optional spanOrigin parameter
  // TODO (v11): remove this backwards-compatible code and only accept the options parameter
  const { spanOrigin = 'auto.http.browser', propagateTraceparent = false } =
    typeof spanOriginOrOptions === 'object' ? spanOriginOrOptions : { spanOrigin: spanOriginOrOptions };

  const client = getClient();
  const hasParent = !!getActiveSpan();
  // With span streaming, we always emit http.client spans, even without a parent span
  const shouldEmitSpan = hasParent || (!!client && hasSpanStreamingEnabled(client));

  const span =
    shouldCreateSpanResult && shouldEmitSpan
      ? startInactiveSpan(getSpanStartOptions(url, method, spanOrigin))
      : new SentryNonRecordingSpan();

  if (shouldCreateSpanResult && !shouldEmitSpan) {
    client?.recordDroppedEvent('no_parent_span', 'span');
  }

  handlerData.fetchData.__span = span.spanContext().spanId;
  spans[span.spanContext().spanId] = span;