apity

Simple request logging middleware for Express. Sends logs to Apity Router.

Installation

npm install apity

Quick Start

import express from 'express';
import { apityLogger } from 'apity';

const app = express();

app.use(express.json());
app.use(apityLogger({ appId: 'your-app-uuid' }));

// Your routes...
app.get('/api/users', (req, res) => {
  res.json({ users: [] });
});

app.listen(3000);

Configuration

apityLogger({
  // Required
  appId: string,       // UUID from Apity Router Master DB

  // Optional
  routerUrl?: string,          // Router URL (default: https://router.apity.io)
  ignorePaths?: string[],      // Paths to skip (default: ['/health', '/', '/favicon.ico'])
  sensitiveHeaders?: string[], // Additional headers to mask (default includes: authorization, cookie, x-api-key)
  sensitiveFields?: string[],  // Additional body fields to mask (default includes: password, token, secret)
  silent?: boolean,            // Suppress error logs (default: false)
  debug?: boolean,             // Enable debug logging (default: false)
  enableMetrics?: boolean,     // Enable server metrics collection (CPU, Memory) (default: false)
  metricsInterval?: number     // Metrics collection interval in seconds (default: 30)
});

Server Metrics

Enable automatic collection of server metrics (CPU, Memory):

app.use(apityLogger({
  appId: 'your-app-uuid',
  enableMetrics: true,        // Enable metrics collection
  metricsInterval: 30,        // Collect every 30 seconds
}));

Metrics are automatically sent to the router and stored in the server_metrics table. See Client Metrics Setup for details.

What Gets Logged

Database (metadata)

• HTTP method, path, status code
• Duration (ms)
• User ID & username (if authenticated)
• Client IP, device type, OS, app version
• Query & path parameters
• Request/response sizes
• Error flag

S3 (full log)

• Complete request (headers, body)
• Complete response (headers, body)
• Truncated if too large (10KB request, 50KB response)

Debug Mode

Enable debug logging to see what's happening:

app.use(apityLogger({
  appId: 'your-app-uuid',
  debug: true
}));

Output:

[apity] 🚀 Logger initialized
[apity]    App ID: your-app-uuid
[apity]    Router URL: https://router.apity.io
[apity]    Ignore paths: /health, /, /favicon.ico
[apity] 📥 Incoming request: GET /api/users
[apity] 📤 Response sent: GET /api/users → 200 (45ms)
[apity] 📤 Sending log to https://router.apity.io/api/v1/logs
[apity]    Method: GET /api/users
[apity]    Status: 200, Duration: 45ms
[apity] ✅ Log sent successfully (120ms)

Features

✅ Non-blocking - Logs are sent asynchronously after response
✅ Auto-masking - Sensitive data (passwords, tokens) automatically hidden
✅ User-Agent parsing - Extracts device type, OS, app version
✅ TypeScript - Full type definitions included
✅ Zero config - Works out of the box with sensible defaults
✅ Debug mode - Verbose logging for troubleshooting

Environment Variables

You can use environment variables for the app ID:

app.use(apityLogger({
  appId: process.env.APITY_APP_ID!
}));

# .env
APITY_APP_ID=your-uuid

License

MIT