How Node.js Skills Improve DevOps Engineer Job Opportunities

// check-health.mjs - run: node check-health.mjs
const services = [
  "https://staging.example.com/health",
  "https://api.staging.example.com/health",
];

const results = await Promise.all(services.map(async (url) => {
  const start = Date.now();
  try {
    const res = await fetch(url, { signal: AbortSignal.timeout(5000) });
    return { url, status: res.status, ms: Date.now() - start };
  } catch (err) {
    return { url, status: "DOWN", ms: Date.now() - start };
  }
}));

console.table(results);
process.exitCode = results.some(r => r.status !== 200) ? 1 : 0;

// disk.mjs - wrap a shell command and parse output
import { execFile } from "node:child_process";
import { promisify } from "node:util";
const run = promisify(execFile);

const { stdout } = await run("df", ["-h", "/"]);
const usage = stdout.trim().split("\n")[1].split(/\s+/)[4];
console.log(`Root disk usage: ${usage}`);

// server.js - health endpoint and graceful shutdown
import http from "node:http";

let ready = true;
const server = http.createServer((req, res) => {
  if (req.url === "/health") return res.end("ok");
  if (req.url === "/ready") {
    res.statusCode = ready ? 200 : 503;
    return res.end(ready ? "ready" : "shutting down");
  }
  res.end("hello");
});
server.listen(3000);

process.on("SIGTERM", () => {
  ready = false;                       // fail readiness first
  server.close(() => process.exit(0)); // finish in-flight requests
  setTimeout(() => process.exit(1), 10000).unref();
});

# Kubernetes container probes for the server above
livenessProbe:
  httpGet: { path: /health, port: 3000 }
  periodSeconds: 10
readinessProbe:
  httpGet: { path: /ready, port: 3000 }
  periodSeconds: 5
resources:
  limits: { memory: "512Mi", cpu: "500m" }

// index.mjs - AWS Lambda (Node.js runtime)
export const handler = async (event) => {
  const records = event.Records ?? [];
  for (const r of records) {
    console.log("New object:", r.s3?.object?.key);
  }
  return { statusCode: 200, body: JSON.stringify({ processed: records.length }) };
};
// Triggered by S3 uploads; logs appear in CloudWatch

# In the pipeline, after checkout
npm ci                          # install exactly from lockfile
npm audit --audit-level=high    # fail on high/critical issues
npm test
# Review audit findings; not every issue affects your code,
# but each one needs a decision.

// cleanup.mjs - list (or delete) old build folders
import { readdir, stat, rm } from "node:fs/promises";
import { parseArgs } from "node:util";
import path from "node:path";

const { values } = parseArgs({ options: {
  dir:    { type: "string", default: "./builds" },
  days:   { type: "string", default: "7" },
  delete: { type: "boolean", default: false },
}});

const cutoff = Date.now() - Number(values.days) * 86400000;
for (const name of await readdir(values.dir)) {
  const full = path.join(values.dir, name);
  const info = await stat(full);
  if (info.isDirectory() && info.mtimeMs < cutoff) {
    console.log(values.delete ? "Deleting" : "Would delete", full);
    if (values.delete) await rm(full, { recursive: true });
  }
}

FROM node:20-alpine
WORKDIR /app
ENV NODE_ENV=production
COPY package*.json ./
RUN npm ci --omit=dev
COPY . .
USER node
EXPOSE 3000
CMD ["node", "server.js"]

Node.js for DevOps engineers
1. JavaScript basics: async/await, modules, errors
2. Node core: fs, path, child_process, http
3. Write 3 automation scripts for your lab
4. Build a small CLI with parseArgs
5. Run a Node service in Docker + Kubernetes with probes
6. Add npm ci + npm audit to a CI pipeline
7. Deploy one Lambda function with IaC