Fix request detail load failures

backend/app/routers/requests.py

@@ -118,6 +118,7 @@ def _cache_get(key: str) -> Optional[Dict[str, Any]]:
 
 def _cache_set(key: str, payload: Dict[str, Any]) -> None:
     _detail_cache[key] = (time.time() + CACHE_TTL_SECONDS, payload)
+    _failed_detail_cache.pop(key, None)
 
 
 def _status_label_with_jellyfin(current_status: Any, jellyfin_available: bool) -> str:
@@ -169,7 +170,6 @@ async def _request_is_available_in_jellyfin(
                 return True
     availability_cache[cache_key] = False
     return False
-    _failed_detail_cache.pop(key, None)
 
 
 def _failure_cache_has(key: str) -> bool:

backend/tests/test_backend_quality.py

@@ -11,6 +11,7 @@ from backend.app.config import settings
 from backend.app.network_security import request_trusts_forwarded_headers, validate_notification_target_url
 from backend.app.routers import auth as auth_router
 from backend.app.routers import portal as portal_router
+from backend.app.routers import requests as requests_router
 from backend.app.routers import status as status_router
 from backend.app.security import PASSWORD_POLICY_MESSAGE, validate_password_policy
 from backend.app.services import password_reset
@@ -117,6 +118,22 @@ class ServiceStatusTests(unittest.IsolatedAsyncioTestCase):
         self.assertIn("credentials", result["message"].lower())
 
 
+class RequestCacheTests(unittest.TestCase):
+    def tearDown(self) -> None:
+        requests_router._detail_cache.clear()
+        requests_router._failed_detail_cache.clear()
+
+    def test_successful_detail_cache_write_clears_prior_failure(self) -> None:
+        key = "request:123"
+        requests_router._failure_cache_set(key)
+        self.assertTrue(requests_router._failure_cache_has(key))
+
+        requests_router._cache_set(key, {"id": 123})
+
+        self.assertFalse(requests_router._failure_cache_has(key))
+        self.assertEqual(requests_router._cache_get(key), {"id": 123})
+
+
 class DatabaseEmailTests(TempDatabaseMixin, unittest.TestCase):
     def test_set_user_email_is_case_insensitive(self) -> None:
         created = db.create_user_if_missing(

frontend/app/requests/[id]/page.tsx

@@ -55,6 +55,44 @@ type ActionHistory = {
   created_at: string
 }
 
+const readApiError = async (response: Response, fallback: string) => {
+  try {
+    const contentType = response.headers.get('content-type') ?? ''
+    if (contentType.includes('application/json')) {
+      const payload = await response.json()
+      if (typeof payload?.detail === 'string' && payload.detail.trim()) {
+        return payload.detail
+      }
+      if (typeof payload?.message === 'string' && payload.message.trim()) {
+        return payload.message
+      }
+    } else {
+      const text = await response.text()
+      if (text.trim()) {
+        return text.trim()
+      }
+    }
+  } catch (error) {
+    console.error(error)
+  }
+  return fallback
+}
+
+const isSnapshotPayload = (value: unknown): value is Snapshot => {
+  if (!value || typeof value !== 'object') {
+    return false
+  }
+  const snapshot = value as Partial<Snapshot>
+  return (
+    typeof snapshot.request_id === 'string' &&
+    typeof snapshot.title === 'string' &&
+    typeof snapshot.request_type === 'string' &&
+    typeof snapshot.state === 'string' &&
+    Array.isArray(snapshot.timeline) &&
+    Array.isArray(snapshot.actions)
+  )
+}
+
 const percentFromTorrent = (torrent: Record<string, any>) => {
   const progress = Number(torrent.progress)
   if (!Number.isNaN(progress) && progress >= 0 && progress <= 1) {
@@ -201,6 +239,7 @@ export default function RequestTimelinePage() {
   const router = useRouter()
   const [snapshot, setSnapshot] = useState<Snapshot | null>(null)
   const [loading, setLoading] = useState(true)
+  const [loadError, setLoadError] = useState<string | null>(null)
   const [showDetails, setShowDetails] = useState(false)
   const [actionMessage, setActionMessage] = useState<string | null>(null)
   const [releaseOptions, setReleaseOptions] = useState<ReleaseOption[]>([])
@@ -214,6 +253,9 @@ export default function RequestTimelinePage() {
       return
     }
     const load = async () => {
+      setLoading(true)
+      setLoadError(null)
+      setSnapshot(null)
       try {
         if (!getToken()) {
           router.push('/login')
@@ -226,12 +268,22 @@ export default function RequestTimelinePage() {
           authFetch(`${baseUrl}/requests/${requestId}/actions?limit=5`),
         ])
 
-        if (snapshotResponse.status === 401) {
+        const authExpired = [snapshotResponse, historyResponse, actionsResponse].some(
+          (response) => response.status === 401
+        )
+        if (authExpired) {
           clearToken()
           router.push('/login')
           return
         }
+        if (!snapshotResponse.ok) {
+          const message = await readApiError(snapshotResponse, 'Unable to load this request.')
+          throw new Error(message)
+        }
         const snapshotData = await snapshotResponse.json()
+        if (!isSnapshotPayload(snapshotData)) {
+          throw new Error('Unable to load this request.')
+        }
         setSnapshot(snapshotData)
         setReleaseOptions([])
         setSearchRan(false)
@@ -251,6 +303,9 @@ export default function RequestTimelinePage() {
         }
       } catch (error) {
         console.error(error)
+        setLoadError(
+          error instanceof Error && error.message ? error.message : 'Unable to load this request.'
+        )
       } finally {
         setLoading(false)
       }
@@ -328,8 +383,12 @@ export default function RequestTimelinePage() {
     )
   }
 
+  if (loadError) {
+    return <main className="card">{loadError}</main>
+  }
+
   if (!snapshot) {
-    return <main className="card">Could not load that request.</main>
+    return <main className="card">Unable to load this request.</main>
   }
 
   const summary =