feat(node-agent): heartbeat agent — CPU/mem stats, health endpoint, bearer token auth

services/node-agent/index.js

@@ -0,0 +1,103 @@
+import express from 'express';
+import os      from 'os';
+
+const MAM_API_URL  = (process.env.MAM_API_URL  || 'http://localhost:3000').replace(/\/$/, '');
+const NODE_TOKEN   =  process.env.NODE_TOKEN   || '';
+const NODE_ROLE    =  process.env.NODE_ROLE    || 'worker';
+const AGENT_PORT   = parseInt(process.env.AGENT_PORT   || '3002',  10);
+const HEARTBEAT_MS = parseInt(process.env.HEARTBEAT_MS || '30000', 10);
+const VERSION      = '1.0.0';
+
+const app = express();
+app.use(express.json());
+
+// ── Health ────────────────────────────────────────────────────────────────
+app.get('/health', (_req, res) => {
+  res.json({
+    ok:       true,
+    hostname: os.hostname(),
+    uptime:   Math.round(process.uptime()),
+    version:  VERSION,
+    role:     NODE_ROLE,
+  });
+});
+
+// ── CPU sampling (500ms window) ───────────────────────────────────────────
+function sampleCpu() {
+  return new Promise(resolve => {
+    const s1 = os.cpus();
+    setTimeout(() => {
+      const s2 = os.cpus();
+      let idle = 0, total = 0;
+      s2.forEach((cpu, i) => {
+        for (const t of Object.keys(cpu.times)) {
+          const d = cpu.times[t] - (s1[i]?.times[t] ?? 0);
+          total += d;
+          if (t === 'idle') idle += d;
+        }
+      });
+      resolve(total > 0 ? Math.round((1 - idle / total) * 10000) / 100 : 0);
+    }, 500);
+  });
+}
+
+function getIp() {
+  for (const ifaces of Object.values(os.networkInterfaces())) {
+    const hit = (ifaces || []).find(a => a.family === 'IPv4' && !a.internal);
+    if (hit) return hit.address;
+  }
+  return null;
+}
+
+// ── Heartbeat ─────────────────────────────────────────────────────────────
+async function heartbeat() {
+  const cpu_usage  = await sampleCpu();
+  const totalMem   = os.totalmem();
+  const freeMem    = os.freemem();
+  const ip_address = getIp();
+
+  const payload = {
+    hostname:     os.hostname(),
+    ip_address,
+    role:         NODE_ROLE,
+    version:      VERSION,
+    api_url:      `http://${ip_address || os.hostname()}:${AGENT_PORT}`,
+    cpu_usage,
+    mem_used_mb:  Math.round((totalMem - freeMem) / 1048576),
+    mem_total_mb: Math.round(totalMem / 1048576),
+  };
+
+  const headers = { 'Content-Type': 'application/json' };
+  if (NODE_TOKEN) headers['Authorization'] = `Bearer ${NODE_TOKEN}`;
+
+  try {
+    const res = await fetch(`${MAM_API_URL}/api/v1/cluster/heartbeat`, {
+      method:  'POST',
+      headers,
+      body:    JSON.stringify(payload),
+      signal:  AbortSignal.timeout(8000),
+    });
+    if (res.ok) {
+      process.stdout.write(
+        `[hb] ${payload.hostname}  cpu=${cpu_usage}%  ` +
+        `mem=${payload.mem_used_mb}/${payload.mem_total_mb}MB\n`
+      );
+    } else {
+      const txt = await res.text().catch(() => '');
+      console.error(`[hb] ${res.status}  ${txt.slice(0, 120)}`);
+    }
+  } catch (err) {
+    console.error(`[hb] failed — ${err.message}`);
+  }
+}
+
+heartbeat();
+setInterval(heartbeat, HEARTBEAT_MS);
+
+app.listen(AGENT_PORT, () => {
+  console.log(`wild-dragon-node-agent v${VERSION}`);
+  console.log(`  Listening  :${AGENT_PORT}`);
+  console.log(`  Primary    ${MAM_API_URL}`);
+  console.log(`  Role       ${NODE_ROLE}`);
+  console.log(`  Heartbeat  every ${HEARTBEAT_MS / 1000}s`);
+});