Allow custom metrics endpoint (#1037)

Co-authored-by: Daniel Jackins <djackins@twilio.com>

.changeset/few-pets-tell.md

@@ -0,0 +1,5 @@
+---
+'@segment/analytics-next': minor
+---
+
+Allow custom metrics endpoint on load

packages/browser/src/browser/__tests__/integration.test.ts

@@ -24,6 +24,7 @@ import {
   lowEntropyTestData,
 } from '../../test-helpers/fixtures/client-hints'
 import { getGlobalAnalytics, NullAnalytics } from '../..'
+import { recordIntegrationMetric } from '../../core/stats/metric-helpers'
 
 let fetchCalls: ReturnType<typeof parseFetchCall>[] = []
 
@@ -655,6 +656,43 @@ describe('Dispatch', () => {
       ]
     `)
   })
+
+  it('respects api and protocol overrides for metrics endpoint', async () => {
+    const [ajs] = await AnalyticsBrowser.load(
+      {
+        writeKey,
+        cdnSettings: {
+          integrations: {
+            'Segment.io': {
+              apiHost: 'cdnSettings.api.io',
+            },
+          },
+          metrics: {
+            flushTimer: 0,
+          },
+        },
+      },
+      {
+        integrations: {
+          'Segment.io': {
+            apiHost: 'new.api.io',
+            protocol: 'http',
+          },
+        },
+      }
+    )
+
+    const event = await ajs.track('foo')
+
+    recordIntegrationMetric(event, {
+      integrationName: 'foo',
+      methodName: 'bar',
+      type: 'action',
+    })
+
+    await sleep(10)
+    expect(fetchCalls[1].url).toBe('http://new.api.io/m')
+  })
 })
 
 describe('Group', () => {

packages/browser/src/browser/index.ts

@@ -357,7 +357,16 @@ async function loadAnalytics(
   const plugins = settings.plugins ?? []
 
   const classicIntegrations = settings.classicIntegrations ?? []
-  Stats.initRemoteMetrics(legacySettings.metrics)
+
+  const segmentLoadOptions = options.integrations?.['Segment.io'] as
+    | SegmentioSettings
+    | undefined
+
+  Stats.initRemoteMetrics({
+    ...legacySettings.metrics,
+    host: segmentLoadOptions?.apiHost ?? legacySettings.metrics?.host,
+    protocol: segmentLoadOptions?.protocol,
+  })
 
   // needs to be flushed before plugins are registered
   flushPreBuffer(analytics, preInitBuffer)

packages/browser/src/core/stats/remote-metrics.ts

@@ -8,6 +8,7 @@ export interface MetricsOptions {
   sampleRate?: number
   flushTimer?: number
   maxQueueSize?: number
+  protocol?: 'http' | 'https'
 }
 
 /**
@@ -56,6 +57,7 @@ export class RemoteMetrics {
   private host: string
   private flushTimer: number
   private maxQueueSize: number
+  private protocol: string
 
   sampleRate: number
   queue: RemoteMetric[]
@@ -65,6 +67,7 @@ export class RemoteMetrics {
     this.sampleRate = options?.sampleRate ?? 1
     this.flushTimer = options?.flushTimer ?? 30 * 1000 /* 30s */
     this.maxQueueSize = options?.maxQueueSize ?? 20
+    this.protocol = options?.protocol ?? 'https'
 
     this.queue = []
 
@@ -130,7 +133,7 @@ export class RemoteMetrics {
     this.queue = []
 
     const headers = { 'Content-Type': 'text/plain' }
-    const url = `https://${this.host}/m`
+    const url = `${this.protocol}://${this.host}/m`
 
     return fetch(url, {
       headers,