From 0ae25f191ea4ad2509ced1488b7a13c68b7f5bca Mon Sep 17 00:00:00 2001
From: Neil Fordyce <neil.fordyce@skyscanner.net>
Date: Thu, 23 Jan 2025 20:15:04 +0000
Subject: [PATCH] feat(sdk-trace-base): add stack trace to operation on ended
 Span warning (#5363)

Co-authored-by: Victor <Zeusvictor88@gmail.com>
---
 CHANGELOG.md                                  |  2 ++
 .../opentelemetry-sdk-trace-base/src/Span.ts  |  7 +++++-
 .../test/common/Span.test.ts                  | 25 +++++++++++++++++++
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7aa1c8704d8..47c473998ca 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -55,6 +55,8 @@ For semantic convention package changes, see the [semconv CHANGELOG](packages/se
 
 ### :rocket: (Enhancement)
 
+* feat(sdk-trace-base): add stack trace warning to debug instrumentation [#5363](https://github.com/open-telemetry/opentelemetry-js/pull/5363) @neilfordyce
+
 ### :bug: (Bug Fix)
 
 * fix(sdk-metrics): do not export from `PeriodicExportingMetricReader` when there are no metrics to export. [#5288](https://github.com/open-telemetry/opentelemetry-js/pull/5288) @jacksonweber
diff --git a/packages/opentelemetry-sdk-trace-base/src/Span.ts b/packages/opentelemetry-sdk-trace-base/src/Span.ts
index f28f74a3e1e..c19aefe1d58 100644
--- a/packages/opentelemetry-sdk-trace-base/src/Span.ts
+++ b/packages/opentelemetry-sdk-trace-base/src/Span.ts
@@ -369,8 +369,13 @@ export class SpanImpl implements Span {
 
   private _isSpanEnded(): boolean {
     if (this._ended) {
+      const error = new Error(
+        `Operation attempted on ended Span {traceId: ${this._spanContext.traceId}, spanId: ${this._spanContext.spanId}}`
+      );
+
       diag.warn(
-        `Can not execute the operation on ended Span {traceId: ${this._spanContext.traceId}, spanId: ${this._spanContext.spanId}}`
+        `Cannot execute the operation on ended Span {traceId: ${this._spanContext.traceId}, spanId: ${this._spanContext.spanId}}`,
+        error
       );
     }
     return this._ended;
diff --git a/packages/opentelemetry-sdk-trace-base/test/common/Span.test.ts b/packages/opentelemetry-sdk-trace-base/test/common/Span.test.ts
index cff451c43c2..18b78728b21 100644
--- a/packages/opentelemetry-sdk-trace-base/test/common/Span.test.ts
+++ b/packages/opentelemetry-sdk-trace-base/test/common/Span.test.ts
@@ -281,6 +281,31 @@ describe('Span', () => {
     });
   });
 
+  it('should log a warning attempting to add event to ended span', () => {
+    const span = new SpanImpl({
+      scope: tracer.instrumentationScope,
+      resource: tracer['_resource'],
+      context: ROOT_CONTEXT,
+      spanContext,
+      name,
+      kind: SpanKind.CLIENT,
+      spanLimits: tracer.getSpanLimits(),
+      spanProcessor: tracer['_spanProcessor'],
+    });
+    span.end();
+
+    const warnStub = sinon.spy(diag, 'warn');
+
+    span.addEvent('oops, too late');
+
+    sinon.assert.calledOnce(warnStub);
+    sinon.assert.calledWith(
+      warnStub,
+      sinon.match(/Cannot execute the operation on ended Span/),
+      sinon.match.instanceOf(Error)
+    );
+  });
+
   describe('setAttribute', () => {
     describe('when default options set', () => {
       it('should set an attribute', () => {