Package Exports

response-time
response-time/index.js

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (response-time) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

response-time

Response time for Node.js servers.

This module creates a middleware that records the response time for requests in HTTP servers. The "response time" is defined here as the elapsed time from when a request enters this middleware to when the headers are written out to the client.

Installation

This is a Node.js module available through the npm registry. Installation is done using the npm install command:

$ npm install response-time

API

var responseTime = require('response-time')

responseTime([options])

Create a middleware that adds a X-Response-Time header to responses. If you don't want to use this module to automatically set a header, please see the section about responseTime(fn).

Options

The responseTime function accepts an optional options object that may contain any of the following keys:

digits

The fixed number of digits to include in the output, which is always in milliseconds, defaults to 3 (ex: 2.300ms).

The name of the header to set, defaults to X-Response-Time.

suffix

Boolean to indicate if units of measurement suffix should be added to the output, defaults to true (ex: 2.300ms vs 2.300).

responseTime(fn)

Create a new middleware that records the response time of a request and makes this available to your own function fn. The fn argument will be invoked as fn(req, res, time), where time is a number in milliseconds.

Examples

express/connect

var express = require('express')
var responseTime = require('response-time')

var app = express()

app.use(responseTime())

app.get('/', function (req, res) {
  res.send('hello, world!')
})

vanilla http server

var finalhandler = require('finalhandler')
var http = require('http')
var responseTime = require('response-time')

// create "middleware"
var _responseTime = responseTime()

http.createServer(function (req, res) {
  var done = finalhandler(req, res)
  _responseTime(req, res, function (err) {
    if (err) return done(err)

    // respond to request
    res.setHeader('content-type', 'text/plain')
    res.end('hello, world!')
  })
})

response time metrics

var express = require('express')
var responseTime = require('response-time')
var StatsD = require('node-statsd')

var app = express()
var stats = new StatsD()

stats.socket.on('error', function (error) {
  console.error(error.stack)
})

app.use(responseTime(function (req, res, time) {
  var stat = (req.method + req.url).toLowerCase()
    .replace(/[:.]/g, '')
    .replace(/\//g, '_')
  stats.timing(stat, time)
}))

app.get('/', function (req, res) {
  res.send('hello, world!')
})

License

MIT