add http cache to avoid fetching feeds too often (#1431)

commafeed-client/src/components/metrics/Gauge.tsx

@@ -1,3 +1,4 @@
+import { NumberFormatter } from "@mantine/core"
 import type { MetricGauge } from "app/types"
 
 interface MeterProps {
@@ -5,5 +6,5 @@ interface MeterProps {
 }
 
 export function Gauge(props: MeterProps) {
-    return <span>{props.gauge.value}</span>
+    return <NumberFormatter value={props.gauge.value} thousandSeparator />
 }

commafeed-client/src/pages/admin/MetricsPage.tsx

@@ -23,6 +23,8 @@ const shownGauges: Record<string, string> = {
     "com.commafeed.backend.HttpGetter.pool.size": "HttpGetter current pool size",
     "com.commafeed.backend.HttpGetter.pool.leased": "HttpGetter active connections",
     "com.commafeed.backend.HttpGetter.pool.pending": "HttpGetter waiting for a connection",
+    "com.commafeed.backend.HttpGetter.cache.size": "HttpGetter cached entries",
+    "com.commafeed.backend.HttpGetter.cache.memoryUsage": "HttpGetter cache memory usage",
     "com.commafeed.frontend.ws.WebSocketSessions.users": "WebSocket users",
     "com.commafeed.frontend.ws.WebSocketSessions.sessions": "WebSocket sessions",
 }