fix: cache query status

src/client/queries/status.ts

@@ -12,7 +12,8 @@ export function useStatusQuery() {
 		queryKey: statusKeys.all,
 		queryFn: ({ signal }) => getStatus(signal),
 		refetchInterval: 60_000,
-		refetchIntervalInBackground: false,
+		refetchIntervalInBackground: true,
+		refetchOnWindowFocus: true,
 	});
 }
 

src/worker/routes/status.ts

@@ -9,6 +9,7 @@ import { resolveFavicon } from './monitors';
 
 const DAY_MS = 24 * 60 * 60 * 1000;
 const FAVICON_CACHE_SECONDS = 86_400;
+const STATUS_CACHE_TIME_HEADER = 'X-Upwatch-Status-Cache-Time';
 type ServiceStatus = 'up' | 'degraded' | 'down' | 'unknown' | 'maintenance';
 type OverallStatus = 'operational' | 'degraded' | 'down';
 type DailyAggregate = { monitorId: number; day: Date; totalChecks: number; upChecks: number };
@@ -134,20 +135,34 @@ function statusCacheKey(context: Context<{ Bindings: Env }>): Request {
  * STATUS_CACHE_SECONDS env var to 0 to disable.
  */
 async function cachedStatusResponse(context: Context<{ Bindings: Env }>): Promise<Response | undefined> {
-	if (resolveStatusCacheSeconds(context.env) <= 0) return undefined;
+	const maxAgeSeconds = resolveStatusCacheSeconds(context.env);
+	if (maxAgeSeconds <= 0) return undefined;
 	const cache = edgeCache();
 	if (!cache) return undefined;
 	try {
-		return await cache.match(statusCacheKey(context));
+		const cached = await cache.match(statusCacheKey(context));
+		if (!cached) return undefined;
+		if (!isStatusCacheFresh(cached, maxAgeSeconds)) return undefined;
+		return cached;
 	} catch {
 		return undefined;
 	}
 }
 
+export function isStatusCacheFresh(response: Response, maxAgeSeconds: number, now = Date.now()): boolean {
+	const cachedAt = Number(response.headers.get(STATUS_CACHE_TIME_HEADER));
+	return Number.isFinite(cachedAt) && now - cachedAt < maxAgeSeconds * 1_000;
+}
+
 function jsonWithEdgeCache(context: Context<{ Bindings: Env }>, body: unknown): Response {
 	const seconds = resolveStatusCacheSeconds(context.env);
 	if (seconds <= 0) return Response.json(body);
-	const response = Response.json(body, { headers: { 'Cache-Control': `public, max-age=${seconds}` } });
+	const response = Response.json(body, {
+		headers: {
+			'Cache-Control': `public, max-age=${seconds}`,
+			[STATUS_CACHE_TIME_HEADER]: String(Date.now()),
+		},
+	});
 	const cache = edgeCache();
 	if (cache) {
 		try {

test/status.spec.ts

@@ -2,6 +2,7 @@ import { applyD1Migrations, type D1Migration } from 'cloudflare:test';
 import { env, exports as worker } from 'cloudflare:workers';
 import { beforeAll, beforeEach, describe, expect, it } from 'vitest';
 import { DEGRADED_MESSAGE } from '../src/worker/ai/fallback-message';
+import { isStatusCacheFresh } from '../src/worker/routes/status';
 
 const DAY_MS = 24 * 60 * 60 * 1000;
 
@@ -143,6 +144,17 @@ describe('public status API', () => {
 		}
 	});
 
+	it('only serves status cache entries within the configured TTL', () => {
+		const now = 1_000_000;
+		const fresh = new Response(null, { headers: { 'X-Upwatch-Status-Cache-Time': String(now - 59_999) } });
+		const expired = new Response(null, { headers: { 'X-Upwatch-Status-Cache-Time': String(now - 60_000) } });
+		const legacy = new Response();
+
+		expect(isStatusCacheFresh(fresh, 60, now)).toBe(true);
+		expect(isStatusCacheFresh(expired, 60, now)).toBe(false);
+		expect(isStatusCacheFresh(legacy, 60, now)).toBe(false);
+	});
+
 	it('keeps a service operational while failures are unconfirmed', async () => {
 		await insertMonitor({
 			name: 'Flaky API',