fix(frontend): handle transient network failures on downloadUrl path

src/pages/app/[app].bundle.[bundle].vue

@@ -428,7 +428,7 @@ async function downloadNow() {
     })
     await dialogStore.onDialogDismiss()
   }
-  openVersion(version.value)
+  await openVersion(version.value)
 }
 
 async function openDownload() {

src/services/staleAssetErrors.ts

@@ -16,6 +16,16 @@ const KNOWN_CRAWLER_ERROR_PATTERNS = [
   /Object Not Found Matching Id:\d+(?:,\s*MethodName:[^,]+,\s*ParamCount:\d+)?/i,
 ]
 
+// Transient browser network drops surface as a `fetch` TypeError whose exact
+// wording differs per engine. Anchored so only the standalone browser message
+// (optionally wrapped with a `<context>: ` prefix, e.g. `downloadUrl error: …`)
+// is suppressed — not richer messages like "Failed to fetch organization insights".
+const TRANSIENT_NETWORK_ERROR_PATTERNS = [
+  /^(?:.*: )?Failed to fetch$/i,
+  /^(?:.*: )?Load failed$/i,
+  /^(?:.*: )?NetworkError when attempting to fetch resource\.?$/i,
+]
+
 export function isStaleAssetErrorMessage(message: string | undefined): boolean {
   if (!message)
     return false
@@ -30,6 +40,13 @@ export function isKnownCrawlerNoiseErrorMessage(message: string | undefined): bo
   return KNOWN_CRAWLER_ERROR_PATTERNS.some(pattern => pattern.test(message))
 }
 
+export function isTransientNetworkErrorMessage(message: string | undefined): boolean {
+  if (!message)
+    return false
+
+  return TRANSIENT_NETWORK_ERROR_PATTERNS.some(pattern => pattern.test(message))
+}
+
 interface PostHogExceptionLike {
   value?: unknown
   $exception_value?: unknown
@@ -49,9 +66,15 @@ export function shouldSuppressPostHogExceptionEvent(event: PostHogEventLike): bo
 
   const exception = event.properties?.$exception_list?.[0]
   const exceptionValue = getErrorMessage(exception?.value) ?? getErrorMessage(exception?.$exception_value)
-  if (isStaleAssetErrorMessage(exceptionValue) || isKnownCrawlerNoiseErrorMessage(exceptionValue))
+  if (isSuppressibleNoiseErrorMessage(exceptionValue))
     return true
 
   const fallbackValue = getErrorMessage(event.properties?.$exception_values?.[0])
-  return isStaleAssetErrorMessage(fallbackValue) || isKnownCrawlerNoiseErrorMessage(fallbackValue)
+  return isSuppressibleNoiseErrorMessage(fallbackValue)
+}
+
+function isSuppressibleNoiseErrorMessage(message: string | undefined): boolean {
+  return isStaleAssetErrorMessage(message)
+    || isKnownCrawlerNoiseErrorMessage(message)
+    || isTransientNetworkErrorMessage(message)
 }

src/services/supabase.ts

@@ -295,7 +295,13 @@ export async function downloadUrl(provider: string, userId: string, appId: strin
     return res.url
   }
   catch (e) {
-    throw new Error(`downloadUrl error: ${e instanceof Error ? e.message : String(e)}`)
+    // A transient browser network drop surfaces as a `TypeError` whose wording
+    // differs per engine (Chrome "Failed to fetch", WebKit "Load failed",
+    // Firefox "NetworkError when attempting to fetch resource."). Rethrow it
+    // untouched so transient-network detection can still recognise the message.
+    if (e instanceof TypeError)
+      throw e
+    throw new Error(`downloadUrl error: ${e instanceof Error ? e.message : String(e)}`, { cause: e })
   }
 }
 

src/services/versions.ts

@@ -63,10 +63,21 @@ export async function openVersion(app: Database['public']['Tables']['app_version
   const { t } = i18n.global
 
   let signedURL
-  if (app.r2_path)
-    signedURL = await downloadUrl(app.storage_provider, app.user_id ?? '', app.app_id, app.id)
-  else
+  if (app.r2_path) {
+    try {
+      signedURL = await downloadUrl(app.storage_provider, app.user_id ?? '', app.app_id, app.id)
+    }
+    catch (error) {
+      // Transient network failures throw out of `downloadUrl`; surface them in
+      // the same toast used for the empty-URL case instead of dead-ending.
+      console.error('Error', error)
+      toast.error(t('cannot-get-the-test-'))
+      return
+    }
+  }
+  else {
     signedURL = app.external_url
+  }
 
   if (!signedURL) {
     toast.error(t('cannot-get-the-test-'))

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

@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest'
 
-import { getErrorMessage, isKnownCrawlerNoiseErrorMessage, isStaleAssetErrorMessage, shouldSuppressPostHogExceptionEvent } from '../src/services/staleAssetErrors'
+import { getErrorMessage, isKnownCrawlerNoiseErrorMessage, isStaleAssetErrorMessage, isTransientNetworkErrorMessage, shouldSuppressPostHogExceptionEvent } from '../src/services/staleAssetErrors'
 
 describe('stale asset error helpers', () => {
   it('matches the stale asset errors currently seen in PostHog', () => {
@@ -25,6 +25,38 @@ describe('stale asset error helpers', () => {
     expect(isKnownCrawlerNoiseErrorMessage('Cannot read properties of null (reading \'save\')')).toBe(false)
   })
 
+  it('matches the transient browser network failures seen across engines', () => {
+    expect(isTransientNetworkErrorMessage('Failed to fetch')).toBe(true)
+    expect(isTransientNetworkErrorMessage('Load failed')).toBe(true)
+    expect(isTransientNetworkErrorMessage('NetworkError when attempting to fetch resource.')).toBe(true)
+    // Wrapped by downloadUrl's non-TypeError fallback path
+    expect(isTransientNetworkErrorMessage('downloadUrl error: NetworkError when attempting to fetch resource.')).toBe(true)
+    expect(isTransientNetworkErrorMessage('downloadUrl error: Failed to fetch')).toBe(true)
+  })
+
+  it('does not match richer messages that merely start with the same words', () => {
+    expect(isTransientNetworkErrorMessage('Failed to fetch organization insights')).toBe(false)
+    expect(isTransientNetworkErrorMessage('Failed to fetch dynamically imported module: https://console.capgo.app/assets/dashboard.js')).toBe(false)
+    expect(isTransientNetworkErrorMessage('downloadUrl error: HTTP 500')).toBe(false)
+    expect(isTransientNetworkErrorMessage(undefined)).toBe(false)
+  })
+
+  it('suppresses transient browser network exception events in PostHog', () => {
+    expect(shouldSuppressPostHogExceptionEvent({
+      event: '$exception',
+      properties: {
+        $exception_list: [{ value: 'Failed to fetch' }],
+      },
+    })).toBe(true)
+
+    expect(shouldSuppressPostHogExceptionEvent({
+      event: '$exception',
+      properties: {
+        $exception_values: ['downloadUrl error: NetworkError when attempting to fetch resource.'],
+      },
+    })).toBe(true)
+  })
+
   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')