Fix sample rate check, add integration tests

Author: danieljackins

packages/signals/signals-integration-tests/src/helpers/base-page-object.ts

@@ -7,6 +7,7 @@ import {
   SignalAPIRequestBuffer,
   TrackingAPIRequestBuffer,
 } from './network-utils'
+import { CDNSettings } from '@segment/analytics-next'
 
 export class BasePage {
   protected page!: Page
@@ -41,13 +42,14 @@ export class BasePage {
     page: Page,
     edgeFn: string,
     signalSettings: Partial<SignalsPluginSettingsConfig> = {},
-    options: { updateURL?: (url: string) => string } = {}
+    options: { updateURL?: (url: string) => string } = {},
+    cdnSettings?: Partial<CDNSettings>
   ) {
     logConsole(page)
     this.page = page
     this.network = new PageNetworkUtils(page)
     this.edgeFn = edgeFn
-    await this.setupMockedRoutes()
+    await this.setupMockedRoutes(cdnSettings)
     const url = options.updateURL ? options.updateURL(this.url) : this.url
     await this.page.goto(url, { waitUntil: 'domcontentloaded' })
     void this.invokeAnalyticsLoad({
@@ -92,15 +94,15 @@ export class BasePage {
     return this
   }
 
-  private async setupMockedRoutes() {
+  private async setupMockedRoutes(settings?: Partial<CDNSettings>) {
     // clear any existing saved requests
     this.trackingAPI.clear()
     this.signalsAPI.clear()
 
     await Promise.all([
       this.mockSignalsApi(),
       this.mockTrackingApi(),
-      this.mockCDNSettings(),
+      this.mockCDNSettings(settings),
     ])
   }
 
@@ -203,7 +205,7 @@ export class BasePage {
     })
   }
 
-  async mockCDNSettings() {
+  async mockCDNSettings(settings?: Partial<CDNSettings>) {
     await this.page.route(
       'https://cdn.segment.com/v1/projects/*/settings',
       (route, request) => {
@@ -213,7 +215,7 @@ export class BasePage {
 
         const cdnSettings = new CDNSettingsBuilder({
           writeKey: '<SOME_WRITE_KEY>',
-          baseCDNSettings: {
+          baseCDNSettings: settings ?? {
             edgeFunction: {
               downloadURL: this.edgeFnDownloadURL,
               version: 1,

packages/signals/signals-integration-tests/src/tests/signals-vanilla/signals-ingestion.test.ts

@@ -27,3 +27,50 @@ test('ingestion enabled -> will send the signal', async ({ page }) => {
 
   expect(true).toBe(true)
 })
+
+test('never sends signal when sample rate is 0', async ({ page }) => {
+  await indexPage.loadAndWait(
+    page,
+    basicEdgeFn,
+    {
+      flushAt: 1,
+      enableSignalsIngestion: false,
+    },
+    undefined,
+    {
+      edgeFunction: {
+        downloadURL: 'https://cdn.edgefn.segment.com/MY-WRITEKEY/foo.js',
+        version: 1,
+      },
+      autoInstrumentationSettings: {
+        sampleRate: 0,
+      },
+    }
+  )
+  await indexPage.fillNameInput('John Doe')
+  await page.waitForTimeout(100)
+  expect(indexPage.signalsAPI.getEvents('interaction')).toHaveLength(0)
+})
+
+test('always sends signal when sample rate is 1', async ({ page }) => {
+  await indexPage.loadAndWait(
+    page,
+    basicEdgeFn,
+    {
+      flushAt: 1,
+      enableSignalsIngestion: false,
+    },
+    undefined,
+    {
+      edgeFunction: {
+        downloadURL: 'https://cdn.edgefn.segment.com/MY-WRITEKEY/foo.js',
+        version: 1,
+      },
+      autoInstrumentationSettings: {
+        sampleRate: 1,
+      },
+    }
+  )
+  await indexPage.fillNameInput('John Doe')
+  expect(indexPage.signalsAPI.getEvents('interaction')).toHaveLength(1)
+})

packages/signals/signals/src/core/signals/settings.ts

@@ -64,8 +64,8 @@ export class SignalGlobalSettings {
         if (this.signalsDebug.getEnableSignalsIngestion()) {
           return true
         }
-        if (!this.sampleSuccess) {
-          return false
+        if (this.sampleSuccess) {
+          return true
         }
         return false
       },
@@ -105,9 +105,22 @@ export class SignalGlobalSettings {
         Boolean(val)
       )
     )
+    this.sampleSuccess = this.checkSampleRate(sampleRate ?? 0)
+  }
+  private checkSampleRate(sampleRate: number): boolean {
+    const storage = new WebStorage(window.sessionStorage)
+    const previousSample = storage.getItem<boolean>('segment_sample_success')
+    if (previousSample !== undefined) {
+      return previousSample
+    }
+
     if (sampleRate && Math.random() <= sampleRate) {
-      this.sampleSuccess = true
+      storage.setItem('segment_sample_success', true)
+      return true
     }
+
+    storage.setItem('segment_sample_success', false)
+    return false
   }
 }