fix(analytics): stop capturing exceptions from local dev hosts

src/services/staleAssetErrors.ts

@@ -82,9 +82,41 @@ interface PostHogEventLike {
     $exception_list?: PostHogExceptionLike[]
     $exception_values?: unknown[]
     $current_url?: unknown
+    $host?: unknown
   }
 }
 
+// Local dev-server hosts. The capture gate in posthog.ts skips analytics only
+// when the Supabase host is local, so a developer running the frontend against
+// remote or preprod Supabase still sends events. Their transient compile and
+// hot-reload errors then open production error-tracking issues. Match the page
+// host to drop those events regardless of the Supabase host.
+const LOCAL_DEV_HOST_PATTERNS = [
+  /^localhost$/i,
+  /^127\.0\.0\.1$/,
+  /\.local$/i,
+]
+
+function hostFromUrl(url: unknown): string | undefined {
+  if (typeof url !== 'string' || url === '')
+    return undefined
+
+  try {
+    return new URL(url).host
+  }
+  catch {
+    return undefined
+  }
+}
+
+export function isLocalDevHost(host: unknown): boolean {
+  if (typeof host !== 'string' || host === '')
+    return false
+
+  const hostname = host.replace(/:\d+$/, '')
+  return LOCAL_DEV_HOST_PATTERNS.some(pattern => pattern.test(hostname))
+}
+
 function stripUrlQueryAndHash(url: string | undefined): string | undefined {
   if (!url)
     return undefined
@@ -155,6 +187,9 @@ export function shouldSuppressPostHogExceptionEvent(event: PostHogEventLike): bo
   if (event.event !== '$exception')
     return false
 
+  if (isLocalDevHost(event.properties?.$host) || isLocalDevHost(hostFromUrl(event.properties?.$current_url)))
+    return true
+
   const exception = event.properties?.$exception_list?.[0]
   const exceptionValue = getErrorMessage(exception?.value) ?? getErrorMessage(exception?.$exception_value)
   if (isSuppressibleNoiseErrorMessage(exceptionValue))

tests/stale-asset-errors.unit.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest'
 
-import { getErrorMessage, isComponentResolutionErrorMessage, isInjectedDocumentCodeException, isKnownCrawlerNoiseErrorMessage, isStaleAssetErrorMessage, isTransientNetworkErrorMessage, shouldSuppressPostHogExceptionEvent } from '../src/services/staleAssetErrors'
+import { getErrorMessage, isComponentResolutionErrorMessage, isInjectedDocumentCodeException, isKnownCrawlerNoiseErrorMessage, isLocalDevHost, isStaleAssetErrorMessage, isTransientNetworkErrorMessage, shouldSuppressPostHogExceptionEvent } from '../src/services/staleAssetErrors'
 
 describe('stale asset error helpers', () => {
   it('matches the stale asset errors currently seen in PostHog', () => {
@@ -151,6 +151,52 @@ describe('stale asset error helpers', () => {
     })).toBe(false)
   })
 
+  it('matches local dev-server hosts regardless of port', () => {
+    expect(isLocalDevHost('localhost:5175')).toBe(true)
+    expect(isLocalDevHost('localhost')).toBe(true)
+    expect(isLocalDevHost('127.0.0.1:5173')).toBe(true)
+    expect(isLocalDevHost('capgo.local')).toBe(true)
+    expect(isLocalDevHost('capgo.local:3000')).toBe(true)
+  })
+
+  it('does not match production hosts or malformed values', () => {
+    expect(isLocalDevHost('console.capgo.app')).toBe(false)
+    expect(isLocalDevHost('capgo.app:443')).toBe(false)
+    expect(isLocalDevHost('notlocalhost.com')).toBe(false)
+    expect(isLocalDevHost('')).toBe(false)
+    expect(isLocalDevHost(undefined)).toBe(false)
+  })
+
+  it('suppresses dev-server exception events by page host', () => {
+    // The $host property carries the dev-server host with its port
+    expect(shouldSuppressPostHogExceptionEvent({
+      event: '$exception',
+      properties: {
+        $host: 'localhost:5175',
+        $exception_list: [{ value: 'ReferenceError: disableRollout is not defined' }],
+      },
+    })).toBe(true)
+
+    // Falls back to the host parsed from $current_url when $host is absent
+    expect(shouldSuppressPostHogExceptionEvent({
+      event: '$exception',
+      properties: {
+        $current_url: 'http://localhost:5175/app/1234/channel/production',
+        $exception_list: [{ value: 'ReferenceError: disableRollout is not defined' }],
+      },
+    })).toBe(true)
+
+    // The same exception from the production host is kept
+    expect(shouldSuppressPostHogExceptionEvent({
+      event: '$exception',
+      properties: {
+        $host: 'console.capgo.app',
+        $current_url: 'https://console.capgo.app/app/1234/channel/production',
+        $exception_list: [{ value: 'ReferenceError: disableRollout is not defined' }],
+      },
+    })).toBe(false)
+  })
+
   it('extracts useful messages from arbitrary rejection values', () => {
     expect(getErrorMessage(new Error('Importing a module script failed.'))).toBe('Importing a module script failed.')
     expect(getErrorMessage({ message: 'Unable to preload CSS for /assets/main.css' })).toBe('Unable to preload CSS for /assets/main.css')