Deepseek feat: add input validation, error handling, performance hooks, and session overlap checks across routes

tools/performance.ts

@@ -0,0 +1,61 @@
+import { performance } from "node:perf_hooks";
+
+type DbMetric = {
+  count: number;
+  totalMs: number;
+  maxMs: number;
+  over100Ms: number;
+};
+
+const metrics = new Map<string, DbMetric>();
+
+export async function measureDb<T>(
+  label: string,
+  operation: () => Promise<T>,
+): Promise<T> {
+  const started = performance.now();
+
+  try {
+    return await operation();
+  } finally {
+    const durationMs = performance.now() - started;
+
+    let metric = metrics.get(label);
+    if (!metric) {
+      metric = { count: 0, totalMs: 0, maxMs: 0, over100Ms: 0 };
+      metrics.set(label, metric);
+    }
+
+    metric.count++;
+    metric.totalMs += durationMs;
+    metric.maxMs = Math.max(metric.maxMs, durationMs);
+
+    if (durationMs > 100) {
+      metric.over100Ms++;
+    }
+  }
+}
+
+setInterval(() => {
+  if (metrics.size === 0) return;
+
+  const operations = Object.fromEntries(
+    [...metrics.entries()].map(([label, metric]) => [
+      label,
+      {
+        count: metric.count,
+        avgMs: Number((metric.totalMs / metric.count).toFixed(2)),
+        maxMs: Number(metric.maxMs.toFixed(2)),
+        over100Ms: metric.over100Ms,
+      },
+    ]),
+  );
+
+  console.log(JSON.stringify({
+    type: "database_performance",
+    timestamp: new Date().toISOString(),
+    operations,
+  }));
+
+  metrics.clear();
+}, 10_000).unref();