feat: Streamline sentry-trace, baggage and DSC handling (#14364)

As a first step for
#12385, I looked
though our current implementations, and tried to streamline this. We
have a bunch of somewhat duplicate code there that handles sentry-trace
& baggage headers _mostly_ the same but not _fully_ the same, as well as
relatedly the DSC.

To streamline this, I added some new methods in core:

* `getTraceData` already exists, but was extended to also allow to pass
a specific `span` to it. I updated some code to use this method that
hasn't used it before, and also added some more tests - also around the
ACS and the otel-specific implementation for this.
* For this and edge cases, there are new primitives
`getDynamicSamplingContextFromScope` and `getTraceContextFromScope`
which handle picking these things from given scope etc.

While working on this, I also noticed that `captureCheckIn` in
ServerRuntimeClient was actually not properly working in Node (OTEL), as
it relied on the core way of scope-span coupling. So I also updated this
to actually work as expected.

Author: mydea

.size-limit.js

@@ -132,7 +132,7 @@ module.exports = [
     path: 'packages/vue/build/esm/index.js',
     import: createImport('init'),
     gzip: true,
-    limit: '28 KB',
+    limit: '29 KB',
   },
   {
     name: '@sentry/vue (incl. Tracing)',

dev-packages/browser-integration-tests/suites/integrations/ContextLines/noAddedLines/test.ts

@@ -7,6 +7,7 @@ sentryTest('should not add source context lines to errors from script files', as
   const url = await getLocalTestUrl({ testDir: __dirname });
 
   const eventReqPromise = waitForErrorRequestOnUrl(page, url);
+  await page.waitForFunction('window.Sentry');
 
   const clickPromise = page.locator('#script-error-btn').click();
 

docs/migration/draft-v9-migration-guide.md

@@ -42,6 +42,7 @@
 - Deprecated `transactionNamingScheme` option in `requestDataIntegration`.
 - Deprecated `debugIntegration`. To log outgoing events, use [Hook Options](https://docs.sentry.io/platforms/javascript/configuration/options/#hooks) (`beforeSend`, `beforeSendTransaction`, ...).
 - Deprecated `sessionTimingIntegration`. To capture session durations alongside events, use [Context](https://docs.sentry.io/platforms/javascript/enriching-events/context/) (`Sentry.setContext()`).
+- Deprecated `addTracingHeadersToFetchRequest` method - this was only meant for internal use and is not needed anymore.
 
 ## `@sentry/nestjs`
 

packages/browser/src/tracing/request.ts

@@ -9,24 +9,17 @@ import {
   SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
   SentryNonRecordingSpan,
   getActiveSpan,
-  getClient,
-  getCurrentScope,
-  getDynamicSamplingContextFromClient,
-  getDynamicSamplingContextFromSpan,
-  getIsolationScope,
+  getTraceData,
   hasTracingEnabled,
   instrumentFetchRequest,
   setHttpStatus,
   spanToJSON,
-  spanToTraceHeader,
   startInactiveSpan,
 } from '@sentry/core';
 import {
   addFetchEndInstrumentationHandler,
   addFetchInstrumentationHandler,
   browserPerformanceTimeOrigin,
-  dynamicSamplingContextToSentryBaggageHeader,
-  generateSentryTraceHeader,
   parseUrl,
   stringMatchesSomePattern,
 } from '@sentry/core';
@@ -76,15 +69,17 @@ export interface RequestInstrumentationOptions {
    *
    * Default: true
    */
-  traceXHR: boolean /**
+  traceXHR: boolean;
+
+  /**
    * Flag to disable tracking of long-lived streams, like server-sent events (SSE) via fetch.
    * Do not enable this in case you have live streams or very long running streams.
    *
    * Disabled by default since it can lead to issues with streams using the `cancel()` api
    * (https://github.com/getsentry/sentry-javascript/issues/13950)
    *
    * Default: false
-   */;
+   */
   trackFetchStreamPerformance: boolean;
 
   /**
@@ -401,12 +396,9 @@ export function xhrCallback(
   xhr.__sentry_xhr_span_id__ = span.spanContext().spanId;
   spans[xhr.__sentry_xhr_span_id__] = span;
 
-  const client = getClient();
-
-  if (xhr.setRequestHeader && shouldAttachHeaders(sentryXhrData.url) && client) {
+  if (shouldAttachHeaders(sentryXhrData.url)) {
     addTracingHeadersToXhrRequest(
       xhr,
-      client,
       // If performance is disabled (TWP) or there's no active root span (pageload/navigation/interaction),
       // we do not want to use the span as base for the trace headers,
       // which means that the headers will be generated from the scope and the sampling decision is deferred
@@ -417,22 +409,12 @@ export function xhrCallback(
   return span;
 }
 
-function addTracingHeadersToXhrRequest(xhr: SentryWrappedXMLHttpRequest, client: Client, span?: Span): void {
-  const scope = getCurrentScope();
-  const isolationScope = getIsolationScope();
-  const { traceId, spanId, sampled, dsc } = {
-    ...isolationScope.getPropagationContext(),
-    ...scope.getPropagationContext(),
-  };
+function addTracingHeadersToXhrRequest(xhr: SentryWrappedXMLHttpRequest, span?: Span): void {
+  const { 'sentry-trace': sentryTrace, baggage } = getTraceData({ span });
 
-  const sentryTraceHeader =
-    span && hasTracingEnabled() ? spanToTraceHeader(span) : generateSentryTraceHeader(traceId, spanId, sampled);
-
-  const sentryBaggageHeader = dynamicSamplingContextToSentryBaggageHeader(
-    dsc || (span ? getDynamicSamplingContextFromSpan(span) : getDynamicSamplingContextFromClient(traceId, client)),
-  );
-
-  setHeaderOnXhr(xhr, sentryTraceHeader, sentryBaggageHeader);
+  if (sentryTrace) {
+    setHeaderOnXhr(xhr, sentryTrace, baggage);
+  }
 }
 
 function setHeaderOnXhr(

packages/core/src/baseclient.ts

@@ -32,23 +32,22 @@ import type {
 } from '@sentry/types';
 
 import { getEnvelopeEndpointWithUrlEncodedAuth } from './api';
-import { getIsolationScope } from './currentScopes';
+import { getCurrentScope, getIsolationScope, getTraceContextFromScope } from './currentScopes';
 import { DEBUG_BUILD } from './debug-build';
 import { createEventEnvelope, createSessionEnvelope } from './envelope';
 import type { IntegrationIndex } from './integration';
 import { afterSetupIntegrations } from './integration';
 import { setupIntegration, setupIntegrations } from './integration';
 import type { Scope } from './scope';
 import { updateSession } from './session';
-import { getDynamicSamplingContextFromClient } from './tracing/dynamicSamplingContext';
+import { getDynamicSamplingContextFromScope } from './tracing/dynamicSamplingContext';
 import { createClientReportEnvelope } from './utils-hoist/clientreport';
 import { dsnToString, makeDsn } from './utils-hoist/dsn';
 import { addItemToEnvelope, createAttachmentEnvelopeItem } from './utils-hoist/envelope';
 import { SentryError } from './utils-hoist/error';
 import { isParameterizedString, isPlainObject, isPrimitive, isThenable } from './utils-hoist/is';
 import { consoleSandbox, logger } from './utils-hoist/logger';
 import { checkOrSetAlreadyCaught, uuid4 } from './utils-hoist/misc';
-import { dropUndefinedKeys } from './utils-hoist/object';
 import { SyncPromise, rejectedSyncPromise, resolvedSyncPromise } from './utils-hoist/syncpromise';
 import { parseSampleRate } from './utils/parseSampleRate';
 import { prepareEvent } from './utils/prepareEvent';
@@ -672,7 +671,7 @@ export abstract class BaseClient<O extends ClientOptions> implements Client<O> {
   protected _prepareEvent(
     event: Event,
     hint: EventHint,
-    currentScope?: Scope,
+    currentScope = getCurrentScope(),
     isolationScope = getIsolationScope(),
   ): PromiseLike<Event | null> {
     const options = this.getOptions();
@@ -692,30 +691,18 @@ export abstract class BaseClient<O extends ClientOptions> implements Client<O> {
         return evt;
       }
 
-      const propagationContext = {
-        ...isolationScope.getPropagationContext(),
-        ...(currentScope ? currentScope.getPropagationContext() : undefined),
+      evt.contexts = {
+        trace: getTraceContextFromScope(currentScope),
+        ...evt.contexts,
       };
 
-      const trace = evt.contexts && evt.contexts.trace;
-      if (!trace && propagationContext) {
-        const { traceId: trace_id, spanId, parentSpanId, dsc } = propagationContext;
-        evt.contexts = {
-          trace: dropUndefinedKeys({
-            trace_id,
-            span_id: spanId,
-            parent_span_id: parentSpanId,
-          }),
-          ...evt.contexts,
-        };
+      const dynamicSamplingContext = getDynamicSamplingContextFromScope(this, currentScope);
 
-        const dynamicSamplingContext = dsc ? dsc : getDynamicSamplingContextFromClient(trace_id, this);
+      evt.sdkProcessingMetadata = {
+        dynamicSamplingContext,
+        ...evt.sdkProcessingMetadata,
+      };
 
-        evt.sdkProcessingMetadata = {
-          dynamicSamplingContext,
-          ...evt.sdkProcessingMetadata,
-        };
-      }
       return evt;
     });
   }

packages/core/src/currentScopes.ts

@@ -1,8 +1,9 @@
-import type { Scope } from '@sentry/types';
+import type { Scope, TraceContext } from '@sentry/types';
 import type { Client } from '@sentry/types';
 import { getAsyncContextStrategy } from './asyncContext';
 import { getMainCarrier } from './carrier';
 import { Scope as ScopeClass } from './scope';
+import { dropUndefinedKeys } from './utils-hoist/object';
 import { getGlobalSingleton } from './utils-hoist/worldwide';
 
 /**
@@ -120,3 +121,20 @@ export function withIsolationScope<T>(
 export function getClient<C extends Client>(): C | undefined {
   return getCurrentScope().getClient<C>();
 }
+
+/**
+ * Get a trace context for the given scope.
+ */
+export function getTraceContextFromScope(scope: Scope): TraceContext {
+  const propagationContext = scope.getPropagationContext();
+
+  const { traceId, spanId, parentSpanId } = propagationContext;
+
+  const traceContext: TraceContext = dropUndefinedKeys({
+    trace_id: traceId,
+    span_id: spanId,
+    parent_span_id: parentSpanId,
+  });
+
+  return traceContext;
+}