fix: explain why native discovery cannot scan stopped containers

AppImage/components/lxc-app-panel.tsx

@@ -125,6 +125,7 @@ interface PortDetail {
 interface NativeDiscovery {
   vmid: number
   status: "not_scanned" | "complete" | "partial" | "error" | "busy"
+  issues?: string[]
   stale: boolean
   candidates: DetectedApp[]
 }
@@ -804,7 +805,10 @@ export function LxcAppPanel({ vmid, ctIp, onChange, managed, initialData, oci }:
       if (!isCurrent()) return
       setNativeDiscovery(native)
       if (native.status === "error" || native.status === "busy") {
-        setDetectionNotice({ found: false, text: t("vmLxc.appEditor.nativeScanFailed") })
+        const stopped = native.status === "error" && Array.isArray(native.issues)
+          && native.issues.includes("guest_stopped")
+        setDetectionNotice({ found: false, text: t(stopped
+          ? "vmLxc.appEditor.nativeScanStopped" : "vmLxc.appEditor.nativeScanFailed") })
         return
       }
       const result: Suggestions = await fetchApi(`/api/vms/${vmid}/apps/suggestions`, {

AppImage/messages/en/common.json

@@ -1746,6 +1746,7 @@
       "nativeEvidenceDirectory": "Working directory",
       "nativeEvidenceService": "Service definition",
       "nativeScanFailed": "Application search could not finish. Previous evidence may be outdated; try again.",
+      "nativeScanStopped": "This container is stopped. Application search is only available while the container is running.",
       "nativeScanPartial": "Application search is incomplete. Review the available evidence and try again.",
       "nativeVersionUnknown": "Installed version unknown",
       "nativeEvidenceStale": "Evidence may be outdated or incomplete.",

AppImage/messages/sk/common.json

@@ -1690,6 +1690,7 @@
       "nativeEvidenceDirectory": "Pracovný priečinok",
       "nativeEvidenceService": "Definícia služby",
       "nativeScanFailed": "Vyhľadávanie aplikácií sa nepodarilo dokončiť. Predchádzajúce dôkazy môžu byť zastarané; skús to znova.",
+      "nativeScanStopped": "Kontajner je vypnutý. Vyhľadávanie aplikácií je dostupné iba v spustenom kontajneri.",
       "nativeScanPartial": "Vyhľadávanie aplikácií je neúplné. Skontroluj dostupné dôkazy a skús to znova.",
       "nativeVersionUnknown": "Nainštalovaná verzia nie je známa",
       "nativeEvidenceStale": "Dôkazy môžu byť zastarané alebo neúplné.",

AppImage/scripts/tests/test_native_app_discovery.py

@@ -746,6 +746,27 @@ class Routes(unittest.TestCase):
             scan.assert_not_called()
             read.assert_not_called()
 
+    def test_stopped_scan_route_exposes_reason_and_keeps_cached_evidence(self):
+        item = {'discovery_id': 'native-retained', 'name': 'Retained app',
+                'installation_path': '/opt/retained/server'}
+        previous = {'vmid': 101, 'status': 'complete', 'stale': False,
+                    'scanned_at': time.time(), 'candidates': [item]}
+        native._cache[101] = copy.deepcopy(previous)
+        with patch.object(native, 'scan', side_effect=native.ProbeError('guest_stopped')), \
+             patch.object(lxc_apps, 'load_sidecar', return_value={'apps': []}), \
+             patch.object(lxc_apps, 'get_suggestions') as suggestions, \
+             patch.object(lxc_apps, '_write_sidecar') as write:
+            response = self.client.post('/api/vms/101/apps/native-discovery')
+            self.assertEqual(response.status_code, 200)
+            result = response.get_json()
+            self.assertEqual(result['status'], 'error')
+            self.assertEqual(result['issues'], ['guest_stopped'])
+            self.assertTrue(result['stale'])
+            self.assertEqual(result['candidates'], [item])
+            self.assertEqual(result['scanned_at'], previous['scanned_at'])
+            suggestions.assert_not_called()
+            write.assert_not_called()
+
     def test_actual_lifecycle_marks_last_known_stale_without_scanning(self):
         native._cache[101] = {'vmid': 101, 'status': 'complete', 'stale': False,
                               'candidates': [], 'scanned_at': time.time()}

tests/lxc_updates/test_native_app_discovery_ui.cjs

@@ -27,7 +27,7 @@ function fixture({nativeCandidate = candidate} = {}) {
   let cursor = 0, tree, props, effects = [], states = [], refs = [], effectStates = []
   const calls = [], cachedWrites = []
   let native = {vmid: 101, status: 'not_scanned', candidates: [], stale: false}
-  let holdScan, scanGate, holdSave, saveGate, scanStatus = 'complete'
+  let holdScan, scanGate, holdSave, saveGate, scanStatus = 'complete', scanIssues
   let cacheGate, resolveCache, cachePending = false
   const seed = {sidecar: {vmid: 101, apps: []}, suggestions: {extras: [], port_suggestions: []}}
   const react = {
@@ -56,7 +56,7 @@ function fixture({nativeCandidate = candidate} = {}) {
       }
       if (options.method === 'POST') {
         if (scanGate) await scanGate
-        native = {...native, status: scanStatus, candidates: [nativeCandidate]}
+        native = {...native, status: scanStatus, issues: scanIssues, candidates: [nativeCandidate]}
       }
       return structuredClone(native)
     }
@@ -102,6 +102,7 @@ function fixture({nativeCandidate = candidate} = {}) {
     holdInitialCache: () => {cachePending = true; cacheGate = new Promise(resolve => {resolveCache = resolve})},
     resolveInitialCache: () => resolveCache(),
     setScanStatus: value => {scanStatus = value},
+    setScanIssues: value => {scanIssues = value},
     holdScan: () => {scanGate = new Promise(resolve => {holdScan = resolve})}, resolveScan: () => holdScan(),
     holdSave: () => {saveGate = new Promise(resolve => {holdSave = resolve})}, resolveSave: () => holdSave(),
   }
@@ -162,6 +163,39 @@ async function main() {
   assert.ok(text(failed.tree()).includes('nativeScanFailed'))
   assert.equal(failed.calls.filter(c => c.url.endsWith('/apps/suggestions') && c.method === 'POST').length, 0)
 
+  // Match the collector's public response, including retained stale evidence.
+  // A busy reply may carry an earlier guest_stopped issue from its cache.
+  for (const [status, issues, expected] of [
+    ['error', ['guest_stopped'], 'nativeScanStopped'],
+    ['error', ['status_unknown'], 'nativeScanFailed'],
+    ['error', ['timeout'], 'nativeScanFailed'],
+    ['error', [], 'nativeScanFailed'],
+    ['error', undefined, 'nativeScanFailed'],
+    ['error', 'guest_stopped', 'nativeScanFailed'],
+    ['busy', ['guest_stopped'], 'nativeScanFailed'],
+  ]) {
+    const denied = fixture()
+    denied.setNative({vmid: 101, status: 'complete', stale: true, candidates: [candidate]})
+    denied.render(); await denied.settle()
+    denied.setScanStatus(status); denied.setScanIssues(issues)
+    await denied.button('searchApplications').props.onClick(); denied.render()
+    assert.ok(text(denied.tree()).includes(expected), `${status}/${JSON.stringify(issues)} uses ${expected}`)
+    assert.ok(!text(denied.tree()).includes(expected === 'nativeScanStopped' ? 'nativeScanFailed' : 'nativeScanStopped'))
+    assert.ok(text(denied.tree()).includes('/opt/handmade/server'), 'failure retains prior evidence')
+    assert.equal(denied.calls.filter(c => c.method === 'POST').length, 1, 'only the explicit discovery POST, no suggestion, save or control call')
+    assert.equal(denied.cachedWrites.length, 0, 'failure cannot overwrite registrations')
+    assert.equal(denied.button('searchApplications').props.disabled, false, 'search settles and can be retried')
+  }
+
+  const stoppedLate = fixture()
+  stoppedLate.render(); await stoppedLate.settle()
+  stoppedLate.setScanStatus('error'); stoppedLate.setScanIssues(['guest_stopped'])
+  stoppedLate.holdScan()
+  const stoppedRequest = stoppedLate.button('searchApplications').props.onClick()
+  stoppedLate.render({vmid: 102}); await stoppedLate.settle()
+  stoppedLate.resolveScan(); await stoppedRequest; stoppedLate.render()
+  assert.ok(!text(stoppedLate.tree()).includes('nativeScanStopped'), 'late stopped response cannot label another CT')
+
   const editorSwitch = fixture()
   editorSwitch.render(); await editorSwitch.settle()
   await editorSwitch.button('searchApplications').props.onClick(); editorSwitch.render()