102 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			102 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|  | # vary
 | ||
|  | 
 | ||
|  | [![NPM Version][npm-image]][npm-url] | ||
|  | [![NPM Downloads][downloads-image]][downloads-url] | ||
|  | [![Node.js Version][node-version-image]][node-version-url] | ||
|  | [![Build Status][travis-image]][travis-url] | ||
|  | [![Test Coverage][coveralls-image]][coveralls-url] | ||
|  | 
 | ||
|  | Manipulate the HTTP Vary header | ||
|  | 
 | ||
|  | ## 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 vary | ||
|  | ``` | ||
|  | 
 | ||
|  | ## API
 | ||
|  | 
 | ||
|  | <!-- eslint-disable no-unused-vars --> | ||
|  | 
 | ||
|  | ```js | ||
|  | var vary = require('vary') | ||
|  | ``` | ||
|  | 
 | ||
|  | ### vary(res, field)
 | ||
|  | 
 | ||
|  | Adds the given header `field` to the `Vary` response header of `res`. | ||
|  | This can be a string of a single field, a string of a valid `Vary` | ||
|  | header, or an array of multiple fields. | ||
|  | 
 | ||
|  | This will append the header if not already listed, otherwise leaves | ||
|  | it listed in the current location. | ||
|  | 
 | ||
|  | <!-- eslint-disable no-undef --> | ||
|  | 
 | ||
|  | ```js | ||
|  | // Append "Origin" to the Vary header of the response | ||
|  | vary(res, 'Origin') | ||
|  | ``` | ||
|  | 
 | ||
|  | ### vary.append(header, field)
 | ||
|  | 
 | ||
|  | Adds the given header `field` to the `Vary` response header string `header`. | ||
|  | This can be a string of a single field, a string of a valid `Vary` header, | ||
|  | or an array of multiple fields. | ||
|  | 
 | ||
|  | This will append the header if not already listed, otherwise leaves | ||
|  | it listed in the current location. The new header string is returned. | ||
|  | 
 | ||
|  | <!-- eslint-disable no-undef --> | ||
|  | 
 | ||
|  | ```js | ||
|  | // Get header string appending "Origin" to "Accept, User-Agent" | ||
|  | vary.append('Accept, User-Agent', 'Origin') | ||
|  | ``` | ||
|  | 
 | ||
|  | ## Examples
 | ||
|  | 
 | ||
|  | ### Updating the Vary header when content is based on it
 | ||
|  | 
 | ||
|  | ```js | ||
|  | var http = require('http') | ||
|  | var vary = require('vary') | ||
|  | 
 | ||
|  | http.createServer(function onRequest (req, res) { | ||
|  |   // about to user-agent sniff | ||
|  |   vary(res, 'User-Agent') | ||
|  | 
 | ||
|  |   var ua = req.headers['user-agent'] || '' | ||
|  |   var isMobile = /mobi|android|touch|mini/i.test(ua) | ||
|  | 
 | ||
|  |   // serve site, depending on isMobile | ||
|  |   res.setHeader('Content-Type', 'text/html') | ||
|  |   res.end('You are (probably) ' + (isMobile ? '' : 'not ') + 'a mobile user') | ||
|  | }) | ||
|  | ``` | ||
|  | 
 | ||
|  | ## Testing
 | ||
|  | 
 | ||
|  | ```sh | ||
|  | $ npm test | ||
|  | ``` | ||
|  | 
 | ||
|  | ## License
 | ||
|  | 
 | ||
|  | [MIT](LICENSE) | ||
|  | 
 | ||
|  | [npm-image]: https://img.shields.io/npm/v/vary.svg | ||
|  | [npm-url]: https://npmjs.org/package/vary | ||
|  | [node-version-image]: https://img.shields.io/node/v/vary.svg | ||
|  | [node-version-url]: https://nodejs.org/en/download | ||
|  | [travis-image]: https://img.shields.io/travis/jshttp/vary/master.svg | ||
|  | [travis-url]: https://travis-ci.org/jshttp/vary | ||
|  | [coveralls-image]: https://img.shields.io/coveralls/jshttp/vary/master.svg | ||
|  | [coveralls-url]: https://coveralls.io/r/jshttp/vary | ||
|  | [downloads-image]: https://img.shields.io/npm/dm/vary.svg | ||
|  | [downloads-url]: https://npmjs.org/package/vary |