⚗️[RUM-4780] Remote configuration

packages/core/src/browser/addEventListener.ts

@@ -1,6 +1,5 @@
 import { monitor } from '../tools/monitor'
 import { getZoneJsOriginalValue } from '../tools/getZoneJsOriginalValue'
-import type { Configuration } from '../domain/configuration'
 import type { CookieStore, CookieStoreEventMap, VisualViewport, VisualViewportEventMap } from './types'
 
 export type TrustableEvent<E extends Event = Event> = E & { __ddIsTrusted?: boolean }
@@ -90,7 +89,7 @@ type EventMapFor<T> = T extends Window
  * * returns a `stop` function to remove the listener
  */
 export function addEventListener<Target extends EventTarget, EventName extends keyof EventMapFor<Target> & string>(
-  configuration: Configuration,
+  configuration: { allowUntrustedEvents?: boolean | undefined },
   eventTarget: Target,
   eventName: EventName,
   listener: (event: EventMapFor<Target>[EventName] & { type: EventName }) => void,
@@ -112,7 +111,7 @@ export function addEventListener<Target extends EventTarget, EventName extends k
  * * with `once: true`, the listener will be called at most once, even if different events are listened
  */
 export function addEventListeners<Target extends EventTarget, EventName extends keyof EventMapFor<Target> & string>(
-  configuration: Configuration,
+  configuration: { allowUntrustedEvents?: boolean | undefined },
   eventTarget: Target,
   eventNames: EventName[],
   listener: (event: EventMapFor<Target>[EventName] & { type: EventName }) => void,

packages/core/src/tools/experimentalFeatures.ts

@@ -19,6 +19,7 @@ export enum ExperimentalFeature {
   TOLERANT_RESOURCE_TIMINGS = 'tolerant_resource_timings',
   ENABLE_PRIVACY_FOR_ACTION_NAME = 'enable_privacy_for_action_name',
   MICRO_FRONTEND = 'micro_frontend',
+  REMOTE_CONFIGURATION = 'remote_configuration',
 }
 
 const enabledExperimentalFeatures: Set<ExperimentalFeature> = new Set()

packages/core/src/transport/eventBridge.ts

@@ -1,13 +1,14 @@
 import { endsWith, includes } from '../tools/utils/polyfills'
 import { getGlobalObject } from '../tools/getGlobalObject'
+import type { DefaultPrivacyLevel } from '../domain/configuration'
 
 export interface BrowserWindowWithEventBridge extends Window {
   DatadogEventBridge?: DatadogEventBridge
 }
 
 export interface DatadogEventBridge {
   getCapabilities?(): string
-  getPrivacyLevel?(): string
+  getPrivacyLevel?(): DefaultPrivacyLevel
   getAllowedWebViewHosts(): string
   send(msg: string): void
 }

packages/core/test/requests.ts

@@ -279,6 +279,7 @@ class StubEventEmitter {
 class StubXhr extends StubEventEmitter {
   public static onSend: (xhr: StubXhr) => void | undefined
   public response: string | undefined = undefined
+  public responseText: string | undefined = undefined
   public status: number | undefined = undefined
   public readyState: number = XMLHttpRequest.UNSENT
   public onreadystatechange: () => void = noop
@@ -313,6 +314,7 @@ class StubXhr extends StubEventEmitter {
     }
     this.hasEnded = true
     this.response = response
+    this.responseText = response
     this.status = status
     this.readyState = XMLHttpRequest.DONE
 

packages/rum-core/src/boot/preStartRum.spec.ts

@@ -8,12 +8,17 @@ import {
   TrackingConsent,
   createTrackingConsentState,
   DefaultPrivacyLevel,
+  addExperimentalFeatures,
+  ExperimentalFeature,
+  resetExperimentalFeatures,
 } from '@datadog/browser-core'
 import type { Clock } from '@datadog/browser-core/test'
 import {
   cleanupSyntheticsWorkerValues,
   initEventBridgeStub,
+  interceptRequests,
   mockClock,
+  mockExperimentalFeatures,
   mockSyntheticsWorkerValues,
 } from '@datadog/browser-core/test'
 import type { HybridInitConfiguration, RumConfiguration, RumInitConfiguration } from '../domain/configuration'
@@ -393,6 +398,48 @@ describe('preStartRum', () => {
         })
       })
     })
+
+    describe('remote configuration', () => {
+      let interceptor: ReturnType<typeof interceptRequests>
+
+      beforeEach(() => {
+        interceptor = interceptRequests()
+      })
+
+      afterEach(() => {
+        interceptor.restore()
+      })
+
+      describe('when remote_configuration ff is enabled', () => {
+        it('should start with the remote configuration when a remoteConfigurationId is provided', (done) => {
+          mockExperimentalFeatures([ExperimentalFeature.REMOTE_CONFIGURATION])
+
+          interceptor.withStubXhr((xhr) => {
+            xhr.complete(200, '{"sessionSampleRate":50}')
+
+            expect(doStartRumSpy.calls.mostRecent().args[0].sessionSampleRate).toEqual(50)
+            done()
+          })
+
+          const strategy = createPreStartStrategy({}, getCommonContextSpy, createTrackingConsentState(), doStartRumSpy)
+          strategy.init({
+            ...DEFAULT_INIT_CONFIGURATION,
+            remoteConfigurationId: '123',
+          })
+        })
+      })
+
+      describe('when remote_configuration ff is disabled', () => {
+        it('should start without the remote configuration when a remoteConfigurationId is provided', () => {
+          const strategy = createPreStartStrategy({}, getCommonContextSpy, createTrackingConsentState(), doStartRumSpy)
+          strategy.init({
+            ...DEFAULT_INIT_CONFIGURATION,
+            remoteConfigurationId: '123',
+          })
+          expect(doStartRumSpy.calls.mostRecent().args[0].sessionSampleRate).toEqual(100)
+        })
+      })
+    })
   })
 
   describe('getInternalContext', () => {
@@ -417,14 +464,18 @@ describe('preStartRum', () => {
   describe('initConfiguration', () => {
     let strategy: Strategy
     let initConfiguration: RumInitConfiguration
+    let interceptor: ReturnType<typeof interceptRequests>
 
     beforeEach(() => {
+      interceptor = interceptRequests()
       strategy = createPreStartStrategy({}, getCommonContextSpy, createTrackingConsentState(), doStartRumSpy)
       initConfiguration = { ...DEFAULT_INIT_CONFIGURATION, service: 'my-service', version: '1.4.2', env: 'dev' }
     })
 
     afterEach(() => {
       cleanupSyntheticsWorkerValues()
+      interceptor.restore()
+      resetExperimentalFeatures()
     })
 
     it('is undefined before init', () => {
@@ -452,6 +503,22 @@ describe('preStartRum', () => {
 
       expect(strategy.initConfiguration).toEqual(initConfiguration)
     })
+
+    it('returns the initConfiguration with the remote configuration when a remoteConfigurationId is provided', (done) => {
+      addExperimentalFeatures([ExperimentalFeature.REMOTE_CONFIGURATION])
+      interceptor.withStubXhr((xhr) => {
+        xhr.complete(200, '{"sessionSampleRate":50}')
+
+        expect(strategy.initConfiguration?.sessionSampleRate).toEqual(50)
+        done()
+      })
+
+      const strategy = createPreStartStrategy({}, getCommonContextSpy, createTrackingConsentState(), doStartRumSpy)
+      strategy.init({
+        ...DEFAULT_INIT_CONFIGURATION,
+        remoteConfigurationId: '123',
+      })
+    })
   })
 
   describe('buffers API calls before starting RUM', () => {

packages/rum-core/src/boot/preStartRum.ts

@@ -9,8 +9,10 @@ import {
   clocksNow,
   assign,
   getEventBridge,
-  addTelemetryConfiguration,
+  ExperimentalFeature,
+  isExperimentalFeatureEnabled,
   initFeatureFlags,
+  addTelemetryConfiguration,
 } from '@datadog/browser-core'
 import type { TrackingConsentState, DeflateWorker } from '@datadog/browser-core'
 import {
@@ -20,7 +22,7 @@ import {
 } from '../domain/configuration'
 import type { CommonContext } from '../domain/contexts/commonContext'
 import type { ViewOptions } from '../domain/view/trackViews'
-import { serializeRumConfiguration } from '../domain/configuration'
+import { fetchAndApplyRemoteConfiguration, serializeRumConfiguration } from '../domain/configuration'
 import type { RumPublicApiOptions, Strategy } from './rumPublicApi'
 import type { StartRumResult } from './startRum'
 
@@ -73,29 +75,62 @@ export function createPreStartStrategy(
     bufferApiCalls.drain(startRumResult)
   }
 
+  function doInit(initConfiguration: RumInitConfiguration) {
+    const eventBridgeAvailable = canUseEventBridge()
+    if (eventBridgeAvailable) {
+      initConfiguration = overrideInitConfigurationForBridge(initConfiguration)
+    }
+
+    // Update the exposed initConfiguration to reflect the bridge and remote configuration overrides
+    cachedInitConfiguration = initConfiguration
+    addTelemetryConfiguration(serializeRumConfiguration(initConfiguration))
+
+    if (cachedConfiguration) {
+      displayAlreadyInitializedError('DD_RUM', initConfiguration)
+      return
+    }
+
+    const configuration = validateAndBuildRumConfiguration(initConfiguration)
+    if (!configuration) {
+      return
+    }
+
+    if (!eventBridgeAvailable && !configuration.sessionStoreStrategyType) {
+      display.warn('No storage available for session. We will not send any data.')
+      return
+    }
+
+    if (configuration.compressIntakeRequests && !eventBridgeAvailable && startDeflateWorker) {
+      deflateWorker = startDeflateWorker(
+        configuration,
+        'Datadog RUM',
+        // Worker initialization can fail asynchronously, especially in Firefox where even CSP
+        // issues are reported asynchronously. For now, the SDK will continue its execution even if
+        // data won't be sent to Datadog. We could improve this behavior in the future.
+        noop
+      )
+      if (!deflateWorker) {
+        // `startDeflateWorker` should have logged an error message explaining the issue
+        return
+      }
+    }
+
+    cachedConfiguration = configuration
+    trackingConsentState.tryToInit(configuration.trackingConsent)
+    tryStartRum()
+  }
+
   return {
     init(initConfiguration) {
       if (!initConfiguration) {
         display.error('Missing configuration')
         return
       }
-
       // Set the experimental feature flags as early as possible, so we can use them in most places
       initFeatureFlags(initConfiguration.enableExperimentalFeatures)
 
-      const eventBridgeAvailable = canUseEventBridge()
-      if (eventBridgeAvailable) {
-        initConfiguration = overrideInitConfigurationForBridge(initConfiguration)
-      }
-
       // Expose the initial configuration regardless of initialization success.
       cachedInitConfiguration = initConfiguration
-      addTelemetryConfiguration(serializeRumConfiguration(initConfiguration))
-
-      if (cachedConfiguration) {
-        displayAlreadyInitializedError('DD_RUM', initConfiguration)
-        return
-      }
 
       // If we are in a Synthetics test configured to automatically inject a RUM instance, we want
       // to completely discard the customer application RUM instance by ignoring their init() call.
@@ -105,34 +140,14 @@ export function createPreStartStrategy(
         return
       }
 
-      const configuration = validateAndBuildRumConfiguration(initConfiguration)
-      if (!configuration) {
-        return
-      }
-
-      if (!eventBridgeAvailable && !configuration.sessionStoreStrategyType) {
-        display.warn('No storage available for session. We will not send any data.')
-        return
-      }
-
-      if (configuration.compressIntakeRequests && !eventBridgeAvailable && startDeflateWorker) {
-        deflateWorker = startDeflateWorker(
-          configuration,
-          'Datadog RUM',
-          // Worker initialization can fail asynchronously, especially in Firefox where even CSP
-          // issues are reported asynchronously. For now, the SDK will continue its execution even if
-          // data won't be sent to Datadog. We could improve this behavior in the future.
-          noop
-        )
-        if (!deflateWorker) {
-          // `startDeflateWorker` should have logged an error message explaining the issue
-          return
-        }
+      if (
+        initConfiguration.remoteConfigurationId &&
+        isExperimentalFeatureEnabled(ExperimentalFeature.REMOTE_CONFIGURATION)
+      ) {
+        fetchAndApplyRemoteConfiguration(initConfiguration, doInit)
+      } else {
+        doInit(initConfiguration)
       }
-
-      cachedConfiguration = configuration
-      trackingConsentState.tryToInit(configuration.trackingConsent)
-      tryStartRum()
     },
 
     get initConfiguration() {

packages/rum-core/src/domain/configuration.spec.ts → packages/rum-core/src/domain/configuration/configuration.spec.ts

@@ -4,8 +4,12 @@ import {
   EXHAUSTIVE_INIT_CONFIGURATION,
   mockExperimentalFeatures,
   SERIALIZED_EXHAUSTIVE_INIT_CONFIGURATION,
-} from '../../../core/test'
-import type { ExtractTelemetryConfiguration, CamelToSnakeCase, MapInitConfigurationKey } from '../../../core/test'
+} from '@datadog/browser-core/test'
+import type {
+  ExtractTelemetryConfiguration,
+  CamelToSnakeCase,
+  MapInitConfigurationKey,
+} from '@datadog/browser-core/test'
 import type { RumInitConfiguration } from './configuration'
 import { DEFAULT_PROPAGATOR_TYPES, serializeRumConfiguration, validateAndBuildRumConfiguration } from './configuration'
 
@@ -471,6 +475,7 @@ describe('serializeRumConfiguration', () => {
       trackViewsManually: true,
       trackResources: true,
       trackLongTasks: true,
+      remoteConfigurationId: '123',
     }
 
     type MapRumInitConfigurationKey<Key extends string> = Key extends keyof InitConfiguration
@@ -479,7 +484,7 @@ describe('serializeRumConfiguration', () => {
         ? `use_${CamelToSnakeCase<Key>}`
         : Key extends 'trackLongTasks'
           ? 'track_long_task' // oops
-          : Key extends 'applicationId' | 'subdomain'
+          : Key extends 'applicationId' | 'subdomain' | 'remoteConfigurationId'
             ? never
             : CamelToSnakeCase<Key>
 

packages/rum-core/src/domain/configuration.ts → packages/rum-core/src/domain/configuration/configuration.ts

@@ -14,10 +14,10 @@ import {
   isExperimentalFeatureEnabled,
   ExperimentalFeature,
 } from '@datadog/browser-core'
-import type { RumEventDomainContext } from '../domainContext.types'
-import type { RumEvent } from '../rumEvent.types'
-import { isTracingOption } from './tracing/tracer'
-import type { PropagatorType, TracingOption } from './tracing/tracer.types'
+import type { RumEventDomainContext } from '../../domainContext.types'
+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']
 
@@ -52,6 +52,7 @@ export interface RumInitConfiguration extends InitConfiguration {
    * See [Content Security Policy guidelines](https://docs.datadoghq.com/integrations/content_security_policy_logs/?tab=firefox#use-csp-with-real-user-monitoring-and-session-replay) for further information.
    */
   compressIntakeRequests?: boolean | undefined
+  remoteConfigurationId?: string | undefined
 
   // tracing options
   /**

packages/rum-core/src/domain/configuration/index.ts

@@ -0,0 +1,2 @@
+export * from './configuration'
+export * from './remoteConfiguration'