https://github.com/expressjs/response-time
Response time header for node.js
https://github.com/expressjs/response-time
javascript middleware nodejs response-time
Last synced: 6 months ago
JSON representation
Response time header for node.js
- Host: GitHub
- URL: https://github.com/expressjs/response-time
- Owner: expressjs
- License: mit
- Created: 2014-02-08T18:51:40.000Z (almost 12 years ago)
- Default Branch: master
- Last Pushed: 2024-10-22T11:35:21.000Z (about 1 year ago)
- Last Synced: 2024-10-29T14:24:24.449Z (about 1 year ago)
- Topics: javascript, middleware, nodejs, response-time
- Language: JavaScript
- Homepage:
- Size: 62.5 KB
- Stars: 465
- Watchers: 23
- Forks: 70
- Open Issues: 3
-
Metadata Files:
- Readme: README.md
- Changelog: HISTORY.md
- License: LICENSE
Awesome Lists containing this project
README
# response-time
[![NPM Version][npm-version-image]][npm-url]
[![NPM Downloads][npm-downloads-image]][npm-url]
[![Node.js Version][node-image]][node-url]
[![Build Status][ci-image]][ci-url]
[![Test Coverage][coveralls-image]][coveralls-url]
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](https://nodejs.org/en/) module available through the
[npm registry](https://www.npmjs.com/). Installation is done using the
[`npm install` command](https://docs.npmjs.com/getting-started/installing-npm-packages-locally):
```sh
$ npm install response-time
```
## API
```js
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)`](#responsetimefn).
#### 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`).
##### header
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
```js
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
```js
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
```js
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](LICENSE)
[npm-version-image]: https://badgen.net/npm/v/response-time
[npm-url]: https://npmjs.org/package/response-time
[npm-downloads-image]: https://badgen.net/npm/dm/response-time
[node-image]: https://badgen.net/npm/node/response-time
[node-url]: https://nodejs.org/en/download
[ci-image]: https://badgen.net/github/checks/express/response-time/master?label=ci
[ci-url]: https://github.com/express/response-time/actions/workflows/ci.yml
[coveralls-image]: https://badgen.net/coveralls/c/github/express/response-time/master
[coveralls-url]: https://coveralls.io/r/express/response-time?branch=master