# api-health-middleware

**Express middleware to report per-request API health to a monitoring backend.**

This middleware logs API requests, response times, and status codes to a remote health endpoint. Designed to be lightweight and non-blocking, it works with any Express.js application.

---

## Installation

```bash
# From npm
npm install api-health-middleware

# Or locally via file
npm install /path/to/api-health-middleware

Usage

const express = require('express');
const healthMonitor = require('api-health-middleware');

const app = express();

// Initialize middleware with your API key
app.use(
  healthMonitor({
    apiKey: "YOUR_API_KEY"
  })
);

app.get('/hello', (req, res) => {
  res.send('Hello World!');
});

app.listen(3000, () => {
  console.log('Server running on port 3000');
});

Configuration Options

| Option | Type | Description | Required | | ------ | ------ | ---------------------------------- | -------- | | apiKey | string | Your API key for the health server | Yes |

How It Works

• Measures request duration using process.hrtime.bigint().

• Captures:

  • HTTP method
  • Endpoint URL
  • Status code
  • Response time in milliseconds
  • IP and User-Agent

• Automatically ignores logging requests sent to /logs/health to prevent recursion.

• Non-blocking and fails silently if the health server is unreachable.

Notes

• Requires Node.js 18+ for native fetch. For Node < 18, install node-fetch and import it:

const fetch = require('node-fetch');

• Compatible with Express.js v4+.

Development

Clone the repository and link locally:

cd api-health-middleware
npm link

# In your app project
npm link api-health-middleware

License

MIT © Tarun Thakur