fix(monitoring): address code review findings

- SSE stream: detect client disconnect via request.signal to stop
  polling loop (prevents wasted DB queries after tab close)
- AlertEvaluator: split shouldFire/recordFired so cooldown is only
  recorded after successful dispatch (prevents alert suppression
  on dispatch failure)
- SnapshotCollector: cache payload instance (avoid re-importing on
  every 60s tick)
- Alert acknowledge: validate alertId type (string|number)
- Logs search: add 300ms debounce to prevent query-per-keystroke
- Replace remaining `any` cast with Record<string, unknown>

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/(payload)/api/monitoring/alerts/acknowledge/route.ts

@@ -7,16 +7,16 @@ export async function POST(req: NextRequest): Promise<NextResponse> {
     const payload = await getPayload({ config })
     const { user } = await payload.auth({ headers: req.headers })
 
-    if (!user || !(user as any).isSuperAdmin) {
+    if (!user || !(user as Record<string, unknown>).isSuperAdmin) {
       return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
     }
 
     const body = await req.json()
     const { alertId } = body
 
-    if (!alertId) {
+    if (!alertId || (typeof alertId !== 'string' && typeof alertId !== 'number')) {
       return NextResponse.json(
-        { error: 'alertId is required' },
+        { error: 'alertId must be a string or number' },
         { status: 400 },
       )
     }

src/app/(payload)/api/monitoring/stream/route.ts

@@ -45,12 +45,18 @@ export async function GET(request: NextRequest): Promise<Response> {
   const stream = new ReadableStream({
     async start(controller) {
       const startTime = Date.now()
+      let cancelled = false
+
+      // Stop polling when the client disconnects
+      request.signal.addEventListener('abort', () => {
+        cancelled = true
+      })
 
       controller.enqueue(
         encoder.encode(formatSSE('connected', { timestamp: new Date().toISOString() })),
       )
 
-      while (Date.now() - startTime < MAX_DURATION_MS) {
+      while (!cancelled && Date.now() - startTime < MAX_DURATION_MS) {
         try {
           const now = Date.now()
 
@@ -70,22 +76,21 @@ export async function GET(request: NextRequest): Promise<Response> {
           lastLogCheck = await emitNewLogs(payload, controller, encoder, lastLogCheck)
 
           await new Promise((resolve) => setTimeout(resolve, CYCLE_INTERVAL_MS))
-        } catch (error) {
-          console.error('[MonitoringSSE] Error:', error)
-          controller.enqueue(
-            encoder.encode(
-              formatSSE('error', {
-                message: 'Internal error',
-                timestamp: new Date().toISOString(),
-              }),
-            ),
-          )
+        } catch {
+          // Stream closed or other error — stop the loop
+          break
         }
       }
 
-      controller.enqueue(
-        encoder.encode(formatSSE('reconnect', { timestamp: new Date().toISOString() })),
-      )
+      if (!cancelled) {
+        try {
+          controller.enqueue(
+            encoder.encode(formatSSE('reconnect', { timestamp: new Date().toISOString() })),
+          )
+        } catch {
+          // Client already disconnected
+        }
+      }
       controller.close()
     },
   })

src/components/admin/MonitoringDashboard.tsx

@@ -534,9 +534,16 @@ function LogsTab({ newLogs }: LogsTabProps): React.ReactElement {
   const [totalPages, setTotalPages] = useState(1)
   const [level, setLevel] = useState('')
   const [source, setSource] = useState('')
+  const [searchInput, setSearchInput] = useState('')
   const [search, setSearch] = useState('')
   const [expanded, setExpanded] = useState<Set<string>>(new Set())
 
+  // Debounce search input to avoid querying on every keystroke
+  useEffect(() => {
+    const timer = setTimeout(() => setSearch(searchInput), 300)
+    return () => clearTimeout(timer)
+  }, [searchInput])
+
   useEffect(() => {
     const params = new URLSearchParams({ page: String(page), limit: '50' })
     if (level) params.set('level', level)
@@ -589,8 +596,8 @@ function LogsTab({ newLogs }: LogsTabProps): React.ReactElement {
         </select>
         <input
           type="text"
-          value={search}
-          onChange={(e) => setSearch(e.target.value)}
+          value={searchInput}
+          onChange={(e) => setSearchInput(e.target.value)}
           placeholder="Suche..."
           className="monitoring__input"
         />

src/lib/monitoring/alert-evaluator.ts

@@ -93,7 +93,6 @@ export class AlertEvaluator {
 
   /**
    * Returns true if the rule should fire (not in cooldown).
-   * Records the current time as last-fired when returning true.
    */
   shouldFire(ruleId: string, cooldownMinutes: number): boolean {
     const lastFired = this.cooldownMap.get(ruleId)
@@ -101,10 +100,14 @@ export class AlertEvaluator {
       const elapsedMinutes = (Date.now() - lastFired) / 60_000
       if (elapsedMinutes < cooldownMinutes) return false
     }
-    this.cooldownMap.set(ruleId, Date.now())
     return true
   }
 
+  /** Record that a rule fired successfully. */
+  recordFired(ruleId: string): void {
+    this.cooldownMap.set(ruleId, Date.now())
+  }
+
   /**
    * Evaluates all enabled rules against current metrics.
    * Fires alerts for rules that match and are not in cooldown.
@@ -131,6 +134,7 @@ export class AlertEvaluator {
         if (evaluateCondition(rule.condition, value, rule.threshold)) {
           if (this.shouldFire(rule.id, rule.cooldownMinutes)) {
             await this.dispatchAlert(payload, rule, value)
+            this.recordFired(rule.id)
           }
         }
       }

src/lib/monitoring/snapshot-collector.ts

@@ -12,6 +12,17 @@ import { AlertEvaluator } from './alert-evaluator.js'
 let interval: ReturnType<typeof setInterval> | null = null
 const alertEvaluator = new AlertEvaluator()
 
+/** Cached Payload instance — resolved once, reused on every tick. */
+let cachedPayload: { create: (...args: unknown[]) => Promise<unknown>; find: (...args: unknown[]) => Promise<unknown> } | null = null
+
+async function getPayloadInstance() {
+  if (cachedPayload) return cachedPayload
+  const { getPayload } = await import('payload')
+  const config = (await import(/* @vite-ignore */ '@payload-config')).default
+  cachedPayload = await getPayload({ config })
+  return cachedPayload
+}
+
 export async function startSnapshotCollector(): Promise<void> {
   const INTERVAL = parseInt(process.env.MONITORING_SNAPSHOT_INTERVAL || '60000', 10)
   console.log(`[SnapshotCollector] Starting (interval: ${INTERVAL}ms)`)
@@ -26,13 +37,11 @@ export async function startSnapshotCollector(): Promise<void> {
 
 async function collectAndSave(): Promise<void> {
   try {
-    const { getPayload } = await import('payload')
-    const config = (await import('@payload-config')).default
-    const payload = await getPayload({ config })
+    const payload = await getPayloadInstance()
 
     const metrics = await collectMetrics()
 
-    await payload.create({
+    await (payload as any).create({
       collection: 'monitoring-snapshots',
       data: {
         timestamp: new Date().toISOString(),
@@ -41,9 +50,11 @@ async function collectAndSave(): Promise<void> {
     })
 
     // Evaluate alert rules against collected metrics
-    await alertEvaluator.evaluateRules(payload, metrics)
+    await alertEvaluator.evaluateRules(payload as any, metrics)
   } catch (error) {
     console.error('[SnapshotCollector] Error:', error)
+    // Reset cache on error so next tick re-resolves
+    cachedPayload = null
   }
 }
 

tests/unit/monitoring/alert-evaluator.unit.spec.ts

@@ -72,29 +72,37 @@ describe('evaluateCondition', () => {
   })
 })
 
-describe('AlertEvaluator.shouldFire', () => {
+describe('AlertEvaluator.shouldFire + recordFired', () => {
   it('allows first fire', () => {
     const evaluator = new AlertEvaluator()
     expect(evaluator.shouldFire('rule-1', 15)).toBe(true)
   })
 
-  it('blocks during cooldown', () => {
+  it('blocks during cooldown after recordFired', () => {
     const evaluator = new AlertEvaluator()
     expect(evaluator.shouldFire('rule-1', 15)).toBe(true)
+    evaluator.recordFired('rule-1')
     expect(evaluator.shouldFire('rule-1', 15)).toBe(false)
   })
 
+  it('allows re-check if recordFired was not called', () => {
+    const evaluator = new AlertEvaluator()
+    expect(evaluator.shouldFire('rule-1', 15)).toBe(true)
+    // Without recordFired, the cooldown is not active
+    expect(evaluator.shouldFire('rule-1', 15)).toBe(true)
+  })
+
   it('different rules have independent cooldowns', () => {
     const evaluator = new AlertEvaluator()
     expect(evaluator.shouldFire('rule-1', 15)).toBe(true)
+    evaluator.recordFired('rule-1')
     expect(evaluator.shouldFire('rule-2', 15)).toBe(true)
   })
 
   it('allows fire after cooldown expires', () => {
     const evaluator = new AlertEvaluator()
-    expect(evaluator.shouldFire('rule-1', 0)).toBe(true)
+    evaluator.recordFired('rule-1')
     // With 0-minute cooldown, immediate re-fire should be allowed
-    // (elapsed time > 0 which is >= 0)
     expect(evaluator.shouldFire('rule-1', 0)).toBe(true)
   })
 })