From 7ed50ed33ae8e0c584c25298cd94a551cfbd7838 Mon Sep 17 00:00:00 2001
From: Luca Forstner <luca.forstner@sentry.io>
Date: Mon, 28 Aug 2023 15:42:24 +0100
Subject: [PATCH] fix: Defer tracing decision to downstream SDKs when using SDK
 without performance (#8839)

---
 packages/core/src/scope.ts                              | 1 -
 packages/hub/test/scope.test.ts                         | 4 ++--
 packages/node/test/integrations/http.test.ts            | 5 +++--
 packages/tracing-internal/src/browser/browsertracing.ts | 2 +-
 packages/types/src/tracing.ts                           | 2 +-
 packages/utils/src/tracing.ts                           | 2 +-
 6 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/packages/core/src/scope.ts b/packages/core/src/scope.ts
index b72defc56016..8875f1c996f2 100644
--- a/packages/core/src/scope.ts
+++ b/packages/core/src/scope.ts
@@ -636,6 +636,5 @@ function generatePropagationContext(): PropagationContext {
   return {
     traceId: uuid4(),
     spanId: uuid4().substring(16),
-    sampled: false,
   };
 }
diff --git a/packages/hub/test/scope.test.ts b/packages/hub/test/scope.test.ts
index 982cba766a87..4c0d830340ec 100644
--- a/packages/hub/test/scope.test.ts
+++ b/packages/hub/test/scope.test.ts
@@ -20,7 +20,7 @@ describe('Scope', () => {
       expect(scope._propagationContext).toEqual({
         traceId: expect.any(String),
         spanId: expect.any(String),
-        sampled: false,
+        sampled: undefined,
         dsc: undefined,
         parentSpanId: undefined,
       });
@@ -442,7 +442,7 @@ describe('Scope', () => {
     expect(scope._propagationContext).toEqual({
       traceId: expect.any(String),
       spanId: expect.any(String),
-      sampled: false,
+      sampled: undefined,
     });
     // @ts-expect-error accessing private property
     expect(scope._propagationContext).not.toEqual(oldPropagationContext);
diff --git a/packages/node/test/integrations/http.test.ts b/packages/node/test/integrations/http.test.ts
index e784eb308f54..0f1613a27345 100644
--- a/packages/node/test/integrations/http.test.ts
+++ b/packages/node/test/integrations/http.test.ts
@@ -208,10 +208,11 @@ describe('tracing', () => {
     const baggageHeader = request.getHeader('baggage') as string;
 
     const parts = sentryTraceHeader.split('-');
-    expect(parts.length).toEqual(3);
+
+    // Should not include sampling decision since we don't wanna influence the tracing decisions downstream
+    expect(parts.length).toEqual(2);
     expect(parts[0]).toEqual(traceId);
     expect(parts[1]).toEqual(expect.any(String));
-    expect(parts[2]).toEqual('0');
 
     expect(baggageHeader).toEqual(
       `sentry-environment=production,sentry-release=1.0.0,sentry-user_segment=segmentA,sentry-public_key=dogsarebadatkeepingsecrets,sentry-trace_id=${traceId}`,
diff --git a/packages/tracing-internal/src/browser/browsertracing.ts b/packages/tracing-internal/src/browser/browsertracing.ts
index d01c837d26c2..a11ea7ff2cf2 100644
--- a/packages/tracing-internal/src/browser/browsertracing.ts
+++ b/packages/tracing-internal/src/browser/browsertracing.ts
@@ -364,7 +364,7 @@ export class BrowserTracing implements Integration {
         traceId: idleTransaction.traceId,
         spanId: idleTransaction.spanId,
         parentSpanId: idleTransaction.parentSpanId,
-        sampled: !!idleTransaction.sampled,
+        sampled: idleTransaction.sampled,
       });
     }
 
diff --git a/packages/types/src/tracing.ts b/packages/types/src/tracing.ts
index 11c4a1658d50..7c5b02c45596 100644
--- a/packages/types/src/tracing.ts
+++ b/packages/types/src/tracing.ts
@@ -5,7 +5,7 @@ export type TracePropagationTargets = (string | RegExp)[];
 export interface PropagationContext {
   traceId: string;
   spanId: string;
-  sampled: boolean;
+  sampled?: boolean;
   parentSpanId?: string;
   dsc?: DynamicSamplingContext;
 }
diff --git a/packages/utils/src/tracing.ts b/packages/utils/src/tracing.ts
index f879b856f9f2..6ad839f2b920 100644
--- a/packages/utils/src/tracing.ts
+++ b/packages/utils/src/tracing.ts
@@ -61,7 +61,7 @@ export function tracingContextFromHeaders(
   const propagationContext: PropagationContext = {
     traceId: traceId || uuid4(),
     spanId: uuid4().substring(16),
-    sampled: parentSampled === undefined ? false : parentSampled,
+    sampled: parentSampled,
   };
 
   if (parentSpanId) {