From 75a022a3726264396f8cfc4d338473bb3c0dae69 Mon Sep 17 00:00:00 2001
From: ai-implementer <ai-implementer@gitea-ai-sdlc.scopicdev.com>
Date: Mon, 14 Sep 2026 08:00:44 +0000
Subject: [PATCH] [QOTD-18] Implement global error-handling middleware

Add src/middleware/error.ts with a four-argument Express error handler
that logs errors server-side via console.error and responds with HTTP
500 and a generic { error: 'Internal server error' } body, never
leaking stack traces to the client. Register it last in a new
src/server.ts entry point.
---
 src/middleware/error.ts | 11 +++++++++++
 src/server.ts           | 10 ++++++++++
 2 files changed, 21 insertions(+)
 create mode 100644 src/middleware/error.ts
 create mode 100644 src/server.ts

diff --git a/src/middleware/error.ts b/src/middleware/error.ts
new file mode 100644
index 0000000..cb2ed34
--- /dev/null
+++ b/src/middleware/error.ts
@@ -0,0 +1,11 @@
+import type { NextFunction, Request, Response } from 'express';
+
+export function errorHandler(
+  err: unknown,
+  _req: Request,
+  res: Response,
+  _next: NextFunction
+): void {
+  console.error(err);
+  res.status(500).json({ error: 'Internal server error' });
+}
diff --git a/src/server.ts b/src/server.ts
new file mode 100644
index 0000000..e61c44f
--- /dev/null
+++ b/src/server.ts
@@ -0,0 +1,10 @@
+import express from 'express';
+import { errorHandler } from './middleware/error';
+
+const app = express();
+
+app.use(express.json());
+
+app.use(errorHandler);
+
+export default app;