vnfmarket/src/main/webapp/vnfmarket/node_modules/on-headers/README.md

   1 # on-headers
   2
   3 [![NPM Version][npm-image]][npm-url]
   4 [![NPM Downloads][downloads-image]][downloads-url]
   5 [![Node.js Version][node-version-image]][node-version-url]
   6 [![Build Status][travis-image]][travis-url]
   7 [![Test Coverage][coveralls-image]][coveralls-url]
   8
   9 Execute a listener when a response is about to write headers.
  10
  11 ## Installation
  12
  13 ```sh
  14 $ npm install on-headers
  15 ```
  16
  17 ## API
  18
  19 ```js
  20 var onHeaders = require('on-headers')
  21 ```
  22
  23 ### onHeaders(res, listener)
  24
  25 This will add the listener `listener` to fire when headers are emitted for `res`.
  26 The listener is passed the `response` object as it's context (`this`). Headers are
  27 considered to be emitted only once, right before they are sent to the client.
  28
  29 When this is called multiple times on the same `res`, the `listener`s are fired
  30 in the reverse order they were added.
  31
  32 ## Examples
  33
  34 ```js
  35 var http = require('http')
  36 var onHeaders = require('on-headers')
  37
  38 http
  39 .createServer(onRequest)
  40 .listen(3000)
  41
  42 function addPoweredBy() {
  43   // set if not set by end of request
  44   if (!this.getHeader('X-Powered-By')) {
  45     this.setHeader('X-Powered-By', 'Node.js')
  46   }
  47 }
  48
  49 function onRequest(req, res) {
  50   onHeaders(res, addPoweredBy)
  51
  52   res.setHeader('Content-Type', 'text/plain')
  53   res.end('hello!')
  54 }
  55 ```
  56
  57 ## Testing
  58
  59 ```sh
  60 $ npm test
  61 ```
  62
  63 ## License
  64
  65 [MIT](LICENSE)
  66
  67 [npm-image]: https://img.shields.io/npm/v/on-headers.svg
  68 [npm-url]: https://npmjs.org/package/on-headers
  69 [node-version-image]: https://img.shields.io/node/v/on-headers.svg
  70 [node-version-url]: http://nodejs.org/download/
  71 [travis-image]: https://img.shields.io/travis/jshttp/on-headers/master.svg
  72 [travis-url]: https://travis-ci.org/jshttp/on-headers
  73 [coveralls-image]: https://img.shields.io/coveralls/jshttp/on-headers/master.svg
  74 [coveralls-url]: https://coveralls.io/r/jshttp/on-headers?branch=master
  75 [downloads-image]: https://img.shields.io/npm/dm/on-headers.svg
  76 [downloads-url]: https://npmjs.org/package/on-headers