@chabdulwahab/api-spy

A zero-dependency, lightweight Express.js middleware that intercepts stdout/stderr streams to render a sticky real-time performance and metrics dashboard at the bottom of the terminal.

Features

• Zero external dependencies.
• Dual-module distribution (CommonJS and ESM).
• Under 5KB footprint after compilation and minification.
• Clean stdout/stderr interception keeping application log scrollback legible.
• Live concurrent request counting, cumulative traffic stats, and RAM consumption telemetry.
• Micro-cache identifying the 5 slowest endpoint routes.

Installation

npm install @chabdulwahab/api-spy

Usage

Registering Middleware

const express = require('express');
const { apiSpy } = require('@chabdulwahab/api-spy');

const app = express();

app.use(apiSpy());

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

app.listen(3000);

Configuration Options

The middleware accepts a configuration object to customize behavior:

app.use(apiSpy({
  enabled: true // Force dashboard execution (default: process.stdout.isTTY check)
}));

Programmatic Metrics Access

You can read telemetry data programmatically for external logging or APM sync:

const { apiSpyMetrics } = require('@chabdulwahab/api-spy');

// Structure of apiSpyMetrics:
// {
//   a: 0,                   // Active requests
//   t: 0,                   // Total requests
//   c: [0, 0, 0, 0, 0, 0],  // HTTP status class counts (index maps to status/100)
//   s: [                    // Cache of top 5 slowest routes
//        { m: 'GET', p: '/api/users', l: 12.5, h: 4 }
//      ]
// }

License

MIT