feat(tracing): Add additional dynamic sampling context items to baggage and envelope headers

Author: Lms24

packages/core/src/envelope.ts

@@ -1,5 +1,4 @@
 import {
-  BaggageObj,
   DsnComponents,
   Event,
   EventEnvelope,
@@ -13,7 +12,7 @@ import {
   SessionEnvelope,
   SessionItem,
 } from '@sentry/types';
-import { createEnvelope, dropUndefinedKeys, dsnToString } from '@sentry/utils';
+import { createEnvelope, dropUndefinedKeys, dsnToString, getSentryBaggageItems } from '@sentry/utils';
 
 /** Extract sdk info from from the API metadata */
 function getSdkMetadataForEnvelopeHeader(metadata?: SdkMetadata): SdkInfo | undefined {
@@ -77,14 +76,14 @@ export function createEventEnvelope(
 
   enhanceEventWithSdkInfo(event, metadata && metadata.sdk);
 
+  const envelopeHeaders = createEventEnvelopeHeaders(event, sdkInfo, tunnel, dsn);
+
   // Prevent this data (which, if it exists, was used in earlier steps in the processing pipeline) from being sent to
   // sentry. (Note: Our use of this property comes and goes with whatever we might be debugging, whatever hacks we may
   // have temporarily added, etc. Even if we don't happen to be using it at some point in the future, let's not get rid
   // of this `delete`, lest we miss putting it back in the next time the property is in use.)
   delete event.sdkProcessingMetadata;
 
-  const envelopeHeaders = createEventEnvelopeHeaders(event, sdkInfo, tunnel, dsn);
-
   const eventItem: EventItem = [
     {
       type: eventType,
@@ -101,8 +100,9 @@ function createEventEnvelopeHeaders(
   tunnel: string | undefined,
   dsn: DsnComponents,
 ): EventEnvelopeHeaders {
-  const baggage = event.contexts && (event.contexts.baggage as BaggageObj);
-  const { environment, release, transaction, userid, usersegment } = baggage || {};
+  const baggage = event.sdkProcessingMetadata && event.sdkProcessingMetadata.baggage;
+  const { environment, release, transaction, userid, usersegment, samplerate } =
+    (baggage && getSentryBaggageItems(baggage)) || {};
 
   return {
     event_id: event.event_id as string,
@@ -119,9 +119,10 @@ function createEventEnvelopeHeaders(
           // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
           trace_id: (event.contexts!.trace as Record<string, unknown>).trace_id as string,
           public_key: dsn.publicKey,
-          environment: environment,
-          release: release,
-          transaction: transaction,
+          sample_rate: samplerate,
+          environment,
+          release,
+          transaction,
           ...((userid || usersegment) && {
             user: {
               id: userid,

packages/core/test/lib/envelope.test.ts

@@ -38,9 +38,9 @@ describe('createEventEnvelope', () => {
             trace: {
               trace_id: '1234',
             },
-            baggage: {
-              release: '1.0.0',
-            },
+          },
+          sdkProcessingMetadata: {
+            baggage: [{ release: '1.0.0' }, '', false],
           },
         },
         { release: '1.0.0', trace_id: '1234', public_key: 'pubKey123' },
@@ -53,10 +53,9 @@ describe('createEventEnvelope', () => {
             trace: {
               trace_id: '1234',
             },
-            baggage: {
-              environment: 'prod',
-              release: '1.0.0',
-            },
+          },
+          sdkProcessingMetadata: {
+            baggage: [{ environment: 'prod', release: '1.0.0' }, '', false],
           },
         },
         { release: '1.0.0', environment: 'prod', trace_id: '1234', public_key: 'pubKey123' },
@@ -69,13 +68,20 @@ describe('createEventEnvelope', () => {
             trace: {
               trace_id: '1234',
             },
-            baggage: {
-              environment: 'prod',
-              release: '1.0.0',
-              userid: 'bob',
-              usersegment: 'segmentA',
-              transaction: 'TX',
-            },
+          },
+          sdkProcessingMetadata: {
+            baggage: [
+              {
+                environment: 'prod',
+                release: '1.0.0',
+                userid: 'bob',
+                usersegment: 'segmentA',
+                transaction: 'TX',
+                samplerate: '0.95',
+              },
+              '',
+              false,
+            ],
           },
         },
         {
@@ -85,6 +91,7 @@ describe('createEventEnvelope', () => {
           transaction: 'TX',
           trace_id: '1234',
           public_key: 'pubKey123',
+          sample_rate: '0.95',
         },
       ],
     ];

packages/hub/src/scope.ts

@@ -454,6 +454,7 @@ export class Scope implements ScopeInterface {
     if (this._transactionName) {
       event.transaction = this._transactionName;
     }
+
     // We want to set the trace context for normal events only if there isn't already
     // a trace context on the event. There is a product feature in place where we link
     // errors with transaction and it relies on that.
@@ -470,7 +471,12 @@ export class Scope implements ScopeInterface {
     event.breadcrumbs = [...(event.breadcrumbs || []), ...this._breadcrumbs];
     event.breadcrumbs = event.breadcrumbs.length > 0 ? event.breadcrumbs : undefined;
 
-    event.sdkProcessingMetadata = this._sdkProcessingMetadata;
+    // Since we're storing dynamic sampling context data in the event.sdkProcessingMetadata
+    // field We have to re-apply it after we applied the Scope's field.
+    // (This is because we're storing this data on the span and not on the scope)
+    const baggage = event.sdkProcessingMetadata && event.sdkProcessingMetadata.baggage;
+    event.sdkProcessingMetadata = this._sdkProcessingMetadata || {};
+    event.sdkProcessingMetadata.baggage = baggage;
 
     return this._notifyEventProcessors([...getGlobalEventProcessors(), ...this._eventProcessors], event, hint);
   }

packages/integration-tests/suites/tracing/baggage/test.ts

@@ -8,6 +8,7 @@ Sentry.init({
   integrations: [new Integrations.BrowserTracing({ tracingOrigins: [/.*/] })],
   environment: 'production',
   tracesSampleRate: 1,
+  debug: true,
 });
 
 Sentry.configureScope(scope => {

packages/integration-tests/suites/tracing/baggage/init.js renamed to packages/integration-tests/suites/tracing/envelope-header/init.js

@@ -0,0 +1,28 @@
+import { expect } from '@playwright/test';
+import { EventEnvelopeHeaders } from '@sentry/types';
+
+import { sentryTest } from '../../../utils/fixtures';
+import { envelopeHeaderRequestParser, getFirstSentryEnvelopeRequest } from '../../../utils/helpers';
+
+sentryTest(
+  'should send dynamic sampling context data in transaction envelope header',
+  async ({ getLocalTestPath, page }) => {
+    const url = await getLocalTestPath({ testDir: __dirname });
+
+    const envHeader = await getFirstSentryEnvelopeRequest<EventEnvelopeHeaders>(page, url, envelopeHeaderRequestParser);
+
+    expect(envHeader.trace).toBeDefined();
+    expect(envHeader.trace).toEqual({
+      environment: 'production',
+      // TODO comment back in once we properly support transaction and user data in Baggage
+      // transaction: 'testTransactionBaggage',
+      // user: {
+      //   id: 'user123',
+      //   segment: 'segmentB',
+      // },
+      sample_rate: '1',
+      public_key: 'public',
+      trace_id: expect.any(String),
+    });
+  },
+);

packages/integration-tests/suites/tracing/envelope-header/test.ts

@@ -77,7 +77,7 @@ test('Should populate and propagate sentry baggage if sentry-trace header does n
   expect(response).toMatchObject({
     test_data: {
       host: 'somewhere.not.sentry',
-      baggage: 'sentry-environment=prod,sentry-release=1.0',
+      baggage: 'sentry-environment=prod,sentry-release=1.0,sentry-samplerate=1',
     },
   });
 });
@@ -93,7 +93,7 @@ test('Should populate Sentry and propagate 3rd party content if sentry-trace hea
   expect(response).toMatchObject({
     test_data: {
       host: 'somewhere.not.sentry',
-      baggage: 'foo=bar,bar=baz,sentry-environment=prod,sentry-release=1.0',
+      baggage: 'foo=bar,bar=baz,sentry-environment=prod,sentry-release=1.0,sentry-samplerate=1',
     },
   });
 });

packages/node-integration-tests/suites/express/sentry-trace/baggage-header-assign/test.ts

@@ -98,7 +98,7 @@ describe('tracing', () => {
     const baggageHeader = request.getHeader('baggage') as string;
 
     expect(baggageHeader).toBeDefined();
-    expect(baggageHeader).toEqual('sentry-environment=production,sentry-release=1.0.0');
+    expect(baggageHeader).toEqual('sentry-environment=production,sentry-release=1.0.0,sentry-samplerate=1');
   });
 
   it('propagates 3rd party baggage header data to outgoing non-sentry requests', async () => {
@@ -110,7 +110,7 @@ describe('tracing', () => {
     const baggageHeader = request.getHeader('baggage') as string;
 
     expect(baggageHeader).toBeDefined();
-    expect(baggageHeader).toEqual('dog=great,sentry-environment=production,sentry-release=1.0.0');
+    expect(baggageHeader).toEqual('dog=great,sentry-environment=production,sentry-release=1.0.0,sentry-samplerate=1');
   });
 
   it("doesn't attach the sentry-trace header to outgoing sentry requests", () => {

packages/node/test/integrations/http.test.ts

@@ -316,6 +316,8 @@ export class Span implements SpanInterface {
 
     // Only add Sentry baggage items to baggage, if baggage does not exist yet or it is still
     // empty and mutable
+    // TODO: we might want to ditch the isSentryBaggageEmpty condition because it prevents
+    //       custom sentry-values in DSC (added by users in the future)
     const finalBaggage =
       !existingBaggage || (isBaggageMutable(existingBaggage) && isSentryBaggageEmpty(existingBaggage))
         ? this._getBaggageWithSentryValues(existingBaggage)
@@ -374,8 +376,12 @@ export class Span implements SpanInterface {
 
     const { environment, release } = (client && client.getOptions()) || {};
 
+    const metadata = this.transaction && this.transaction.metadata;
+    const sampelRate = metadata && metadata.transactionSampling && metadata.transactionSampling.rate;
+
     environment && setBaggageValue(baggage, 'environment', environment);
     release && setBaggageValue(baggage, 'release', release);
+    sampelRate && setBaggageValue(baggage, 'samplerate', sampelRate.toString());
 
     setBaggageImmutable(baggage);
 

packages/tracing/src/span.ts

@@ -6,7 +6,7 @@ import {
   TransactionContext,
   TransactionMetadata,
 } from '@sentry/types';
-import { dropUndefinedKeys, getSentryBaggageItems, logger } from '@sentry/utils';
+import { dropUndefinedKeys, logger } from '@sentry/utils';
 
 import { Span as SpanClass, SpanRecorder } from './span';
 
@@ -122,15 +122,17 @@ export class Transaction extends SpanClass implements TransactionInterface {
     const transaction: Event = {
       contexts: {
         trace: this.getTraceContext(),
-        baggage: getSentryBaggageItems(this.getBaggage()),
       },
       spans: finishedSpans,
       start_timestamp: this.startTimestamp,
       tags: this.tags,
       timestamp: this.endTimestamp,
       transaction: this.name,
       type: 'transaction',
-      sdkProcessingMetadata: this.metadata,
+      sdkProcessingMetadata: {
+        ...this.metadata,
+        baggage: this.getBaggage(),
+      },
     };
 
     const hasMeasurements = Object.keys(this._measurements).length > 0;

packages/tracing/src/transaction.ts

@@ -1,4 +1,4 @@
-export type AllowedBaggageKeys = 'environment' | 'release' | 'userid' | 'transaction' | 'usersegment';
+export type AllowedBaggageKeys = 'environment' | 'release' | 'userid' | 'transaction' | 'usersegment' | 'samplerate';
 export type BaggageObj = Partial<Record<AllowedBaggageKeys, string> & Record<string, string>>;
 
 /**

packages/types/src/baggage.ts

@@ -12,6 +12,7 @@ import { UserFeedback } from './user';
 export type EventTraceContext = {
   trace_id: Transaction['traceId'];
   public_key: DsnComponents['publicKey'];
+  sample_rate?: string;
   release?: string;
   user?: {
     id?: string;