surface growthbook flags in sentry

src/analytics/index.tsx

@@ -9,6 +9,7 @@ import {Platform} from 'react-native'
 import {type Result, type WidenPrimitives} from '@growthbook/growthbook-react'
 
 import {Logger} from '#/logger'
+import {recordFeatureFlagEvaluation} from '#/logger/sentry/featureFlags'
 import {
   Features,
   features as feats,
@@ -313,6 +314,7 @@ export function AnalyticsFeaturesContext({
         ? sessionMetadataForResult(parentContext, result.experimentResult)
         : undefined,
     )
+    recordFeatureFlagEvaluation(feature, result.value)
   })
   setAttributes(parentContext.metadata)
 

src/logger/sentry/featureFlags.test.ts

@@ -0,0 +1,45 @@
+import {beforeEach, describe, expect, it, jest} from '@jest/globals'
+
+import {
+  featureFlagsIntegration,
+  recordFeatureFlagEvaluation,
+} from '#/logger/sentry/featureFlags'
+
+jest.mock('#/logger/sentry/lib', () => ({
+  Sentry: {
+    featureFlagsIntegration: jest.fn(() => ({
+      addFeatureFlag: jest.fn(),
+    })),
+  },
+}))
+
+describe('recordFeatureFlagEvaluation', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  it('records boolean feature flags', () => {
+    recordFeatureFlagEvaluation('enabled-flag', true)
+    recordFeatureFlagEvaluation('disabled-flag', false)
+
+    expect(featureFlagsIntegration.addFeatureFlag).toHaveBeenNthCalledWith(
+      1,
+      'enabled-flag',
+      true,
+    )
+    expect(featureFlagsIntegration.addFeatureFlag).toHaveBeenNthCalledWith(
+      2,
+      'disabled-flag',
+      false,
+    )
+  })
+
+  it.each([['value'], [1], [['value']], [{value: true}], [null], [undefined]])(
+    'ignores unsupported value %p',
+    value => {
+      recordFeatureFlagEvaluation('non-boolean-flag', value)
+
+      expect(featureFlagsIntegration.addFeatureFlag).not.toHaveBeenCalled()
+    },
+  )
+})

src/logger/sentry/featureFlags.ts

@@ -0,0 +1,13 @@
+import {Sentry} from '#/logger/sentry/lib'
+
+export const featureFlagsIntegration = Sentry.featureFlagsIntegration()
+
+/**
+ * Records a feature flag evaluation on Sentry error events and active spans.
+ * Sentry currently only supports boolean feature flag values.
+ */
+export function recordFeatureFlagEvaluation(name: string, value: unknown) {
+  if (typeof value === 'boolean') {
+    featureFlagsIntegration.addFeatureFlag(name, value)
+  }
+}

src/logger/sentry/setup/index.ts

@@ -1,5 +1,6 @@
 import {getGlobalScope, init} from '@sentry/react-native'
 
+import {featureFlagsIntegration} from '#/logger/sentry/featureFlags'
 import * as env from '#/env'
 
 init({
@@ -10,6 +11,7 @@ init({
   environment: env.ENV,
   dist: env.BUNDLE_IDENTIFIER,
   release: env.RELEASE_VERSION,
+  integrations: [featureFlagsIntegration],
   ignoreErrors: [
     /*
      * Unknown internals errors