toa-morgan

HTTP request logger middleware for Toa.

Modified from https://github.com/expressjs/morgan

Examples

simple toa server

Simple app that will log all request in the Apache combined format to STDOUT

const Toa = require('toa')
const toaMorgan = require('toa-morgan')
 
const app = new Toa()
app.use(toaMorgan())
app.use(function () {
  this.body = 'Hello!'
})
 
app.listen(3000)

write logs to a file

Simple app that will log all requests in the Apache combined format to the file access.log.

const fs = require('fs')
const Toa = require('toa')
const toaMorgan = require('toa-morgan')
 
// create a write stream (in append mode)
const accessLogStream = fs.createWriteStream(__dirname + '/access.log', {flags: 'a'})
 
const app = new Toa()
app.use(toaMorgan('common', {stream: accessLogStream}))
app.use(function () {
  this.body = 'Hello!'
})
 
app.listen(3000)

use custom token formats

Sample app that will use custom token formats. This adds an ID to all requests and displays it using the :id token.

const Toa = require('toa')
const uuid = require('uuid')
const toaMorgan = require('toa-morgan')
 
toaMorgan.token('id', function () {
  return this.state.id
})
 
const app = new Toa()
app.use(toaMorgan(':id :method :url :response-time'))
app.use(function (next) {
  this.state.id = uuid.v4()
  next()
})
 
app.use(function () {
  this.body = 'Hello!'
})
app.listen(3000)

API

const morgan = require('toa-morgan')

morgan([format, options])

Create a new morgan logger middleware function using the given format and options. The format argument may be a string of a predefined name (see below for the names), a string of a format string, or a function that will produce a log entry.

Options

Morgan accepts these properties in the options object.

immediate

Write log line on request instead of response. This means that a requests will be logged even if the server crashes, but data from the response (like the response code, content length, etc.) cannot be logged.

skip

Function to determine if logging is skipped, defaults to false. This function will be called as skip.call(context).

// EXAMPLE: only log error responses
morgan('combined', {
  skip: function () {
    return this.status < 400
  }
})

stream

Output stream for writing log lines, defaults to process.stdout.

Predefined Formats

There are various pre-defined formats provided:

combined

Standard Apache combined log output. It is default format.

:remote-addr - :remote-user [:date[clf]] ":method :url HTTP/:http-version" :status :res[content-length] ":referrer" ":user-agent"

common

Standard Apache common log output.

:remote-addr - :remote-user [:date[clf]] ":method :url HTTP/:http-version" :status :res[content-length]

dev

Concise output colored by response status for development use. The :status token will be colored red for server error codes, yellow for client error codes, cyan for redirection codes, and uncolored for all other codes.

:method :url :status :response-time ms - :res[content-length]

tiny

The minimal output.

:method :url :status :res[content-length] - :response-time ms

Tokens

Creating new tokens

To define a token, simply invoke morgan.token with the name and a callback function. This callback function is expected to return a string value. The value returned is then available as ":type" in this case:

morgan.token('type', function () {
  return this.get('content-type')
})

Calling morgan.token using the same name as an existing token will overwrite that token definition.

:date[format]

The current date and time in UTC. The available formats are:

• clf for the common log format ("10/Oct/2000:13:55:36 +0000")
• iso for the common ISO 8601 date time format (2000-10-10T13:55:36.000Z)
• web for the common RFC 1123 date time format (Tue, 10 Oct 2000 13:55:36 GMT)

If no format is given, then the default is web.

:http-version

The HTTP version of the request.

:method

The HTTP method of the request.

:referrer

The Referrer header of the request. This will use the standard mis-spelled Referer header if exists, otherwise Referrer.

:remote-addr

The remote address of the request. This will use this.ip.

:remote-user

The user, default is "-".

:req[header]

The given header of the request.

:res[header]

The given header of the response.

:response-time

The time between the request coming into morgan and when the response headers are written, in milliseconds.

:status

The status code of the response.

If the request/response cycle completes before a response was sent to the client (for example, the TCP socket closed prematurely by a client aborting the request), then the status will be empty (displayed as "-" in the log).

:url

The URL of the request. This will use this.originalUrl.

:user-agent

The contents of the User-Agent header of the request.

Licences

(The MIT License)