✨ [RUM-1210] Add W3C tracecontext to default propagator types (#2443)

* Ensure both Datadog and Tracecontext headers are present by default
DataDog · Oct 4, 2023 · 4c7860f · 4c7860f
1 parent 4196b47
commit 4c7860f
Show file tree

Hide file tree

Showing 3 changed files with 14 additions and 8 deletions.
diff --git a/packages/rum-core/src/domain/configuration.spec.ts b/packages/rum-core/src/domain/configuration.spec.ts
@@ -1,6 +1,6 @@
 import { DefaultPrivacyLevel, display } from '@datadog/browser-core'
 import type { RumInitConfiguration } from './configuration'
-import { serializeRumConfiguration, validateAndBuildRumConfiguration } from './configuration'
+import { DEFAULT_PROPAGATOR_TYPES, serializeRumConfiguration, validateAndBuildRumConfiguration } from './configuration'
 
 const DEFAULT_INIT_CONFIGURATION = { clientToken: 'xxx', applicationId: 'xxx' }
 
@@ -90,7 +90,7 @@ describe('validateAndBuildRumConfiguration', () => {
           allowedTracingUrls: ['foo'],
           service: 'bar',
         })!.allowedTracingUrls
-      ).toEqual([{ match: 'foo', propagatorTypes: ['datadog'] }])
+      ).toEqual([{ match: 'foo', propagatorTypes: DEFAULT_PROPAGATOR_TYPES }])
     })
 
     it('accepts functions', () => {
@@ -102,7 +102,7 @@ describe('validateAndBuildRumConfiguration', () => {
           allowedTracingUrls: [customOriginFunction],
           service: 'bar',
         })!.allowedTracingUrls
-      ).toEqual([{ match: customOriginFunction, propagatorTypes: ['datadog'] }])
+      ).toEqual([{ match: customOriginFunction, propagatorTypes: DEFAULT_PROPAGATOR_TYPES }])
     })
 
     it('accepts RegExp', () => {
@@ -112,7 +112,7 @@ describe('validateAndBuildRumConfiguration', () => {
           allowedTracingUrls: [/az/i],
           service: 'bar',
         })!.allowedTracingUrls
-      ).toEqual([{ match: /az/i, propagatorTypes: ['datadog'] }])
+      ).toEqual([{ match: /az/i, propagatorTypes: DEFAULT_PROPAGATOR_TYPES }])
     })
 
     it('keeps headers', () => {
@@ -341,12 +341,14 @@ describe('validateAndBuildRumConfiguration', () => {
         expect(serializeRumConfiguration(DEFAULT_INIT_CONFIGURATION).selected_tracing_propagators).toEqual([])
       })
 
-      it('should return Datadog propagator type', () => {
+      it('should return the default propagator types', () => {
         const simpleTracingConfig: RumInitConfiguration = {
           ...DEFAULT_INIT_CONFIGURATION,
           allowedTracingUrls: ['foo'],
         }
-        expect(serializeRumConfiguration(simpleTracingConfig).selected_tracing_propagators).toEqual(['datadog'])
+        expect(serializeRumConfiguration(simpleTracingConfig).selected_tracing_propagators).toEqual(
+          DEFAULT_PROPAGATOR_TYPES
+        )
       })
 
       it('should return all propagator types', () => {

diff --git a/packages/rum-core/src/domain/configuration.ts b/packages/rum-core/src/domain/configuration.ts
@@ -16,6 +16,8 @@ import type { RumEvent } from '../rumEvent.types'
 import { isTracingOption } from './tracing/tracer'
 import type { PropagatorType, TracingOption } from './tracing/tracer.types'
 
+export const DEFAULT_PROPAGATOR_TYPES: PropagatorType[] = ['tracecontext', 'datadog']
+
 export interface RumInitConfiguration extends InitConfiguration {
   // global options
   applicationId: string
@@ -144,7 +146,7 @@ function validateAndBuildTracingOptions(initConfiguration: RumInitConfiguration)
     const tracingOptions: TracingOption[] = []
     initConfiguration.allowedTracingUrls.forEach((option) => {
       if (isMatchOption(option)) {
-        tracingOptions.push({ match: option, propagatorTypes: ['datadog'] })
+        tracingOptions.push({ match: option, propagatorTypes: DEFAULT_PROPAGATOR_TYPES })
       } else if (isTracingOption(option)) {
         tracingOptions.push(option)
       } else {
@@ -170,7 +172,7 @@ function getSelectedTracingPropagators(configuration: RumInitConfiguration): Pro
   if (Array.isArray(configuration.allowedTracingUrls) && configuration.allowedTracingUrls.length > 0) {
     configuration.allowedTracingUrls.forEach((option) => {
       if (isMatchOption(option)) {
-        usedTracingPropagators.add('datadog')
+        DEFAULT_PROPAGATOR_TYPES.forEach((propagatorType) => usedTracingPropagators.add(propagatorType))
       } else if (getType(option) === 'object' && Array.isArray(option.propagatorTypes)) {
         // Ensure we have an array, as we cannot rely on types yet (configuration is provided by users)
         option.propagatorTypes.forEach((propagatorType) => usedTracingPropagators.add(propagatorType))

diff --git a/test/e2e/scenario/rum/tracing.scenario.ts b/test/e2e/scenario/rum/tracing.scenario.ts
@@ -56,10 +56,12 @@ describe('tracing', () => {
       checkTraceAssociatedToRumEvent(intakeRegistry)
     })
 
+  // By default, we send both Datadog and W3C tracecontext headers
   function checkRequestHeaders(rawHeaders: string) {
     const headers: { [key: string]: string } = JSON.parse(rawHeaders)
     expect(headers['x-datadog-trace-id']).toMatch(/\d+/)
     expect(headers['x-datadog-origin']).toBe('rum')
+    expect(headers['traceparent']).toMatch(/^[0-9a-f]{2}-[0-9a-f]{32}-[0-9a-f]{16}-01$/)
     expect(headers['x-foo']).toBe('bar, baz')
   }