feat(node): Allow to configure maxSpanWaitDuration (#12610)

Author: Luca Forstner

packages/node/src/sdk/initOtel.ts

@@ -113,7 +113,11 @@ export function setupOtel(client: NodeClient): BasicTracerProvider {
     }),
     forceFlushTimeoutMillis: 500,
   });
-  provider.addSpanProcessor(new SentrySpanProcessor());
+  provider.addSpanProcessor(
+    new SentrySpanProcessor({
+      timeout: client.getOptions().maxSpanWaitDuration,
+    }),
+  );
 
   // Initialize the provider
   provider.register({

packages/node/src/types.ts

@@ -74,6 +74,17 @@ export interface BaseNodeOptions {
    */
   skipOpenTelemetrySetup?: boolean;
 
+  /**
+   * The max. duration in seconds that the SDK will wait for parent spans to be finished before discarding a span.
+   * The SDK will automatically clean up spans that have no finished parent after this duration.
+   * This is necessary to prevent memory leaks in case of parent spans that are never finished or otherwise dropped/missing.
+   * However, if you have very long-running spans in your application, a shorter duration might cause spans to be discarded too early.
+   * In this case, you can increase this duration to a value that fits your expected data.
+   *
+   * Defaults to 300 seconds (5 minutes).
+   */
+  maxSpanWaitDuration?: number;
+
   /** Callback that is executed when a fatal global error occurs. */
   onFatalError?(this: void, error: Error): void;
 }

packages/node/test/integration/transactions.test.ts

@@ -633,4 +633,63 @@ describe('Integration | Transactions', () => {
       ]),
     );
   });
+
+  it('allows to configure `maxSpanWaitDuration` to capture long running spans', async () => {
+    const transactions: TransactionEvent[] = [];
+    const beforeSendTransaction = jest.fn(event => {
+      transactions.push(event);
+      return null;
+    });
+
+    const now = Date.now();
+    jest.useFakeTimers();
+    jest.setSystemTime(now);
+
+    const logs: unknown[] = [];
+    jest.spyOn(logger, 'log').mockImplementation(msg => logs.push(msg));
+
+    mockSdkInit({
+      enableTracing: true,
+      beforeSendTransaction,
+      maxSpanWaitDuration: 100 * 60,
+    });
+
+    Sentry.startSpanManual({ name: 'test name' }, rootSpan => {
+      const subSpan = Sentry.startInactiveSpan({ name: 'inner span 1' });
+      subSpan.end();
+
+      Sentry.startSpanManual({ name: 'inner span 2' }, innerSpan => {
+        // Child span ends after 10 min
+        setTimeout(
+          () => {
+            innerSpan.end();
+          },
+          10 * 60 * 1_000,
+        );
+      });
+
+      // root span ends after 99 min
+      setTimeout(
+        () => {
+          rootSpan.end();
+        },
+        99 * 10 * 1_000,
+      );
+    });
+
+    // Now wait for 100 mins
+    jest.advanceTimersByTime(100 * 60 * 1_000);
+
+    expect(beforeSendTransaction).toHaveBeenCalledTimes(1);
+    expect(transactions).toHaveLength(1);
+    const transaction = transactions[0]!;
+
+    expect(transaction.transaction).toEqual('test name');
+    const spans = transaction.spans || [];
+
+    expect(spans).toHaveLength(2);
+
+    expect(spans[0]!.description).toEqual('inner span 1');
+    expect(spans[1]!.description).toEqual('inner span 2');
+  });
 });

packages/opentelemetry/src/spanExporter.ts

@@ -33,16 +33,19 @@ import { parseSpanDescription } from './utils/parseSpanDescription';
 type SpanNodeCompleted = SpanNode & { span: ReadableSpan };
 
 const MAX_SPAN_COUNT = 1000;
+const DEFAULT_TIMEOUT = 300; // 5 min
 
 /**
  * A Sentry-specific exporter that converts OpenTelemetry Spans to Sentry Spans & Transactions.
  */
 export class SentrySpanExporter {
   private _flushTimeout: ReturnType<typeof setTimeout> | undefined;
   private _finishedSpans: ReadableSpan[];
+  private _timeout: number;
 
-  public constructor() {
+  public constructor(options?: { timeout?: number }) {
     this._finishedSpans = [];
+    this._timeout = options?.timeout || DEFAULT_TIMEOUT;
   }
 
   /** Export a single span. */
@@ -103,7 +106,7 @@ export class SentrySpanExporter {
    */
   private _cleanupOldSpans(spans = this._finishedSpans): void {
     this._finishedSpans = spans.filter(span => {
-      const shouldDrop = shouldCleanupSpan(span, 5 * 60);
+      const shouldDrop = shouldCleanupSpan(span, this._timeout);
       DEBUG_BUILD &&
         shouldDrop &&
         logger.log(

packages/opentelemetry/src/spanProcessor.ts

@@ -65,9 +65,9 @@ function onSpanEnd(span: Span): void {
 export class SentrySpanProcessor implements SpanProcessorInterface {
   private _exporter: SentrySpanExporter;
 
-  public constructor() {
+  public constructor(options?: { timeout?: number }) {
     setIsSetup('SentrySpanProcessor');
-    this._exporter = new SentrySpanExporter();
+    this._exporter = new SentrySpanExporter(options);
   }
 
   /**