@codephil/logging-middleware-ddog

Express middleware for structured logging to Datadog with pretty console output. Sends logs directly to Datadog's HTTP intake API without requiring the Datadog Agent.

Features

• 🚀 Direct logging to Datadog via HTTP API
• 💅 Pretty console output for local development
• 📊 Automatic HTTP request/response logging
• ⚡ Performance monitoring with memory usage
• 🎯 TypeScript type definitions included
• 🔄 Express middleware compatible

Installation

npm install @codephil/logging-middleware-ddog

Usage

const express = require('express');
const { datadogMiddleware } = require('@codephil/logging-middleware-ddog');

const app = express();

// Initialize the middleware
app.use(datadogMiddleware({
  serviceName: 'your-service-name',    // Optional if set in env
  apiKey: 'your-datadog-api-key',      // Optional if set in env
  nodeEnv: 'development',              // Optional if set in env
  warnThreshold: 1000,                 // Response time warning threshold (ms)
  errorThreshold: 3000                 // Response time error threshold (ms)
}));

// Use the logger in your routes
app.get('/api/users', (req, res) => {
  req.logger.info('Fetching users', { 
    additional: 'context',
    userId: req.user?.id 
  });
  // ... your route logic
});

Environment Variables

The middleware will look for these environment variables if not provided in options:

• DD_API_KEY: Your Datadog API key
• SERVICE_NAME: Your service name
• NODE_ENV: Environment (development, production, etc.)

Options

interface DatadogOptions {
  apiKey?: string;         // Datadog API key
  serviceName?: string;    // Service name for Datadog
  nodeEnv?: string;        // Environment (development, production, etc.)
  logLevel?: string;       // Winston log level
  warnThreshold?: number;  // Response time warning threshold in ms (default: 1000)
  errorThreshold?: number; // Response time error threshold in ms (default: 3000)
}

Console Output

The middleware provides pretty console output for local development:

12:34:56 ℹ️  info: GET /api/users
  → GET /api/users
  ← 200 (45ms)
  ⚡ Performance: 45ms | Memory: 2.5MB

12:34:57 ⚠️  warn: Slow request detected
  → GET /api/tasks
  ← 200 (1250ms)
  ⚡ Performance: 1250ms | Memory: 5.8MB

Status codes are color-coded:

• 2xx: Green (success)
• 3xx: Cyan (redirect)
• 4xx: Yellow (client error)
• 5xx: Red (server error)

Performance metrics are automatically tracked:

• Response time warnings when exceeding thresholds
• Memory usage per request
• Color-coded performance indicators

Datadog Integration

Logs are sent directly to Datadog's HTTP intake API with the following structure:

{
  message: "HTTP Request Completed",
  level: "info",
  ddsource: "nodejs",
  service: "your-service-name",
  http: {
    method: "GET",
    url: "/api/users",
    status_code: 200,
    response_time_ms: 45
  },
  performance: {
    responseTime: 45,
    memoryUsed: 2621440,  // in bytes
    route: "/api/users"
  },
  // ... additional context
}