Migrating from Morgan to http-debugger

Side-by-side comparison and migration guide for Express users.

Quick Comparison

Feature	Morgan	http-debugger
Request body capture	❌	✅
Response body capture	❌	✅
Body truncation	❌	✅ (configurable)
cURL generation	❌	✅
Stream-level capture	❌	✅
Zero runtime deps	✅	✅
TypeScript support	⚠️ (types separate)	✅ (built-in)
Fastify/Hono/Next.js	❌	✅
Web dashboard	❌	✅

Express Migration

Before (Morgan)

const express = require('express')
const morgan = require('morgan')

const app = express()
app.use(morgan('combined'))
// or custom:
app.use(morgan(':method :url :status :res[content-length] - :response-time ms'))

After (http-debugger)

import express from 'express'
import { httpDebugger } from 'http-debugger/express'

const app = express()
app.use(httpDebugger())

Configuration Mapping

Morgan Format Token	http-debugger Equivalent
:method	Auto-captured
:url	Auto-captured (full path + query)
:status	Auto-captured
:res[content-length]	response.size
:response-time	timing.duration
:req[header]	request.headers
:res[header]	response.headers
:req[body]	request.body (with truncation)
:res[body]	response.body (with truncation)

Custom Token → Filter/Options

Morgan Custom Token

morgan.token('user-id', (req) => req.user?.id ?? 'anonymous')
app.use(morgan(':method :url :status :user-id'))

http-debugger Equivalent

app.use(httpDebugger({
  filter: (entry) => {
    // Access user from request context
    return true // log all, or filter as needed
  }
}))
// User info available in: entry.request.headers['x-user-id'] (if you set it)

Output Comparison

Morgan (combined)

::1 - - [28/Jul/2024:10:30:45 +0000] "POST /api/users HTTP/1.1" 201 45 "-" "curl/7.68.0"

http-debugger (default)

→ POST /api/users
  content-type: application/json
  authorization: ***

  Body: {"name":"Alice","email":"alice@example.com"}

← 201 Created (45ms)
  content-type: application/json
  location: /api/users/123

  Body: {"id":"123","name":"Alice","email":"alice@example.com"}
  Size: 67B

  Timing:
    Headers:   1.2ms
    Body Read: 2.1ms
    Handler:   38.5ms
    Response:  3.2ms

  curl: curl -X POST 'http://localhost/api/users' -H 'content-type: application/json' -d '{"name":"Alice","email":"alice@example.com"}'

Advanced Migration

Conditional Logging

Morgan:

app.use(morgan('combined', {
  skip: (req, res) => res.statusCode < 400
}))

http-debugger:

app.use(httpDebugger({
  filter: (entry) => entry.response.statusCode >= 400
}))

Custom Output Stream

Morgan:

const fs = require('fs')
const accessLogStream = fs.createWriteStream('access.log', { flags: 'a' })
app.use(morgan('combined', { stream: accessLogStream }))

http-debugger:

import { httpDebugger } from 'http-debugger/express'
import { formatEntry } from 'http-debugger'
import fs from 'fs'

const logStream = fs.createWriteStream('access.log', { flags: 'a' })

app.use(httpDebugger({
  // Custom console: false, // We'll handle output
 filter: (entry) => {
   logStream.write(formatEntry(entry) + '\n\n')
   return false // Don't double-log to console
 }
}))

Request ID Correlation

Morgan:

app.use((req, res, next) => {
  req.id = crypto.randomUUID()
  res.setHeader('X-Request-ID', req.id)
  next()
})
app.use(morgan(':id :method :url :status'))

http-debugger:

import { v4 as uuidv4 } from 'uuid'

app.use((req, res, next) => {
  req.id = uuidv4()
  res.setHeader('X-Request-ID', req.id)
  next()
})

app.use(httpDebugger({
  // Request ID auto-captured in headers
}))
// Available in: entry.request.headers['x-request-id']

Dashboard Bonus

Morgan has no equivalent. With http-debugger:

app.use(httpDebugger({ dashboard: true }))

Visit http://localhost:3000/__debugger for real-time request inspection.

Checklist

• [ ] Replace morgan() with httpDebugger()
• [ ] Remove custom token definitions (built-in capture is richer)
• [ ] Update custom format strings → use filter option
• [ ] Test body capture with JSON/form-data requests
• [ ] Enable dashboard: true for development
• [ ] Set maxBodySize appropriate for your payloads
• [ ] Verify sanitize: true redacts sensitive headers
• [ ] Check cURL output for failed requests