feat(cluster): node registry API — heartbeat, list, deregister

services/mam-api/src/routes/cluster.js

@@ -0,0 +1,81 @@
+import express from 'express';
+import pool from '../db/pool.js';
+import { requireAuth } from '../middleware/auth.js';
+
+const router = express.Router();
+router.use(requireAuth);
+
+// GET / – list all registered cluster nodes with online status
+router.get('/', async (req, res, next) => {
+  try {
+    const r = await pool.query(
+      `SELECT *,
+              EXTRACT(EPOCH FROM (NOW() - last_seen)) AS stale_seconds
+       FROM cluster_nodes
+       ORDER BY registered_at ASC`
+    );
+    res.json(r.rows.map(row => ({
+      ...row,
+      // online = last heartbeat within 2 minutes
+      online: Number(row.stale_seconds) < 120,
+    })));
+  } catch (err) { next(err); }
+});
+
+// POST /heartbeat – upsert this node's registration
+router.post('/heartbeat', async (req, res, next) => {
+  try {
+    const {
+      hostname, ip_address,
+      role = 'worker', version, api_url,
+      cpu_usage, mem_used_mb, mem_total_mb,
+      metadata,
+    } = req.body;
+
+    if (!hostname) return res.status(400).json({ error: 'hostname is required' });
+
+    const r = await pool.query(
+      `INSERT INTO cluster_nodes
+         (hostname, ip_address, role, version, api_url,
+          cpu_usage, mem_used_mb, mem_total_mb, last_seen, metadata)
+       VALUES ($1,$2,$3,$4,$5,$6,$7,$8,NOW(),$9)
+       ON CONFLICT (hostname) DO UPDATE SET
+         ip_address   = EXCLUDED.ip_address,
+         role         = EXCLUDED.role,
+         version      = EXCLUDED.version,
+         api_url      = EXCLUDED.api_url,
+         cpu_usage    = EXCLUDED.cpu_usage,
+         mem_used_mb  = EXCLUDED.mem_used_mb,
+         mem_total_mb = EXCLUDED.mem_total_mb,
+         last_seen    = NOW(),
+         metadata     = EXCLUDED.metadata
+       RETURNING *`,
+      [
+        hostname,
+        ip_address   || null,
+        role,
+        version      || null,
+        api_url      || null,
+        cpu_usage    != null ? cpu_usage    : null,
+        mem_used_mb  != null ? mem_used_mb  : null,
+        mem_total_mb != null ? mem_total_mb : null,
+        metadata     != null ? JSON.stringify(metadata) : null,
+      ]
+    );
+    res.json(r.rows[0]);
+  } catch (err) { next(err); }
+});
+
+// DELETE /:id – deregister a node
+router.delete('/:id', async (req, res, next) => {
+  try {
+    const r = await pool.query(
+      'DELETE FROM cluster_nodes WHERE id = $1 RETURNING id',
+      [req.params.id]
+    );
+    if (r.rowCount === 0) return res.status(404).json({ error: 'Node not found' });
+    res.json({ ok: true });
+  } catch (err) { next(err); }
+});
+
+export default router;