API-Monitor-Middleware

A lightweight Express middleware to automatically monitor API health.
It tracks requests, responses, errors, response time, and uptime, sending logs to your dashboard (Under Development) using an API key.

This package is plug-and-play — just install it, provide your API key, and it works out-of-the-box.

Features

• Automatic logging of all API requests
• Tracks:
  • Endpoint (/api/users, /login, etc.)
  • HTTP method (GET, POST, PUT, DELETE)
  • Status code (200, 404, 500, etc.)
  • Response time in milliseconds
  • Success / error messages
  • IP address and User-Agent
• Works with Express 4.x and above

Installation

npm i api-health-middleware

Usage
1. Import and Initialize Middleware
const express = require('express');
const app = express();

// Import health monitor middleware
const healthMonitor = require('api-health-middleware');

// Use middleware globally
app.use(
  healthMonitor({
    apiKey: 'YOUR_DASHBOARD_API_KEY', // Required
  })
);

app.get('/api/users', (req, res) => {
  res.json({ message: 'Hello users' });
});

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

2. How It Works

Middleware intercepts every request and response.

Captures metrics: endpoint, method, status, response time, IP, User-Agent.

Sends logs asynchronously to your monitoring dashboard using the API key.

Your dashboard aggregates metrics per project, showing:

Total API calls

Error count

Average response time

Uptime percentage

3. Middleware Configuration Options
Option	Type	Required	Default	Description
apiKey	string	✅ Yes	—	API key generated from your dashboard for authentication
Example Log Object Sent to Dashboard
{
  "timestamp": "2026-02-11T16:24:00.123Z",
  "method": "GET",
  "endpoint": "/users",
  "statusCode": 200,
  "responseTimeMs": 123,
  "success": true,
  "errorMessage": null,
  "ip": "192.168.0.1",
  "userAgent": "PostmanRuntime/7.28.4",
  "projectId": "623d2f6b9e1b0a0012345678"
}

Example Metrics from Dashboard

Total API calls: 120

Error count: 5

Average response time: 135 ms

Uptime: 95.83%

Best Practices

Async logging – middleware sends logs asynchronously to avoid blocking API responses.


Use environments – differentiate production, staging, or development metrics.

Batch logs – optionally batch logs to reduce network calls.

Secure API key – never commit it publicly.

Contributing

We welcome contributions!

Fork the repo

Create a new branch (feature/my-feature)

Run tests:

npm test


Submit a pull request

License

MIT © Your Name

Acknowledgements

Inspired by Postman Monitors and lightweight API monitoring systems.


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