125 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			125 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| /*!
 | |
|  * negotiator
 | |
|  * Copyright(c) 2012 Federico Romero
 | |
|  * Copyright(c) 2012-2014 Isaac Z. Schlueter
 | |
|  * Copyright(c) 2015 Douglas Christopher Wilson
 | |
|  * MIT Licensed
 | |
|  */
 | |
| 
 | |
| 'use strict';
 | |
| 
 | |
| /**
 | |
|  * Cached loaded submodules.
 | |
|  * @private
 | |
|  */
 | |
| 
 | |
| var modules = Object.create(null);
 | |
| 
 | |
| /**
 | |
|  * Module exports.
 | |
|  * @public
 | |
|  */
 | |
| 
 | |
| module.exports = Negotiator;
 | |
| module.exports.Negotiator = Negotiator;
 | |
| 
 | |
| /**
 | |
|  * Create a Negotiator instance from a request.
 | |
|  * @param {object} request
 | |
|  * @public
 | |
|  */
 | |
| 
 | |
| function Negotiator(request) {
 | |
|   if (!(this instanceof Negotiator)) {
 | |
|     return new Negotiator(request);
 | |
|   }
 | |
| 
 | |
|   this.request = request;
 | |
| }
 | |
| 
 | |
| Negotiator.prototype.charset = function charset(available) {
 | |
|   var set = this.charsets(available);
 | |
|   return set && set[0];
 | |
| };
 | |
| 
 | |
| Negotiator.prototype.charsets = function charsets(available) {
 | |
|   var preferredCharsets = loadModule('charset').preferredCharsets;
 | |
|   return preferredCharsets(this.request.headers['accept-charset'], available);
 | |
| };
 | |
| 
 | |
| Negotiator.prototype.encoding = function encoding(available) {
 | |
|   var set = this.encodings(available);
 | |
|   return set && set[0];
 | |
| };
 | |
| 
 | |
| Negotiator.prototype.encodings = function encodings(available) {
 | |
|   var preferredEncodings = loadModule('encoding').preferredEncodings;
 | |
|   return preferredEncodings(this.request.headers['accept-encoding'], available);
 | |
| };
 | |
| 
 | |
| Negotiator.prototype.language = function language(available) {
 | |
|   var set = this.languages(available);
 | |
|   return set && set[0];
 | |
| };
 | |
| 
 | |
| Negotiator.prototype.languages = function languages(available) {
 | |
|   var preferredLanguages = loadModule('language').preferredLanguages;
 | |
|   return preferredLanguages(this.request.headers['accept-language'], available);
 | |
| };
 | |
| 
 | |
| Negotiator.prototype.mediaType = function mediaType(available) {
 | |
|   var set = this.mediaTypes(available);
 | |
|   return set && set[0];
 | |
| };
 | |
| 
 | |
| Negotiator.prototype.mediaTypes = function mediaTypes(available) {
 | |
|   var preferredMediaTypes = loadModule('mediaType').preferredMediaTypes;
 | |
|   return preferredMediaTypes(this.request.headers.accept, available);
 | |
| };
 | |
| 
 | |
| // Backwards compatibility
 | |
| Negotiator.prototype.preferredCharset = Negotiator.prototype.charset;
 | |
| Negotiator.prototype.preferredCharsets = Negotiator.prototype.charsets;
 | |
| Negotiator.prototype.preferredEncoding = Negotiator.prototype.encoding;
 | |
| Negotiator.prototype.preferredEncodings = Negotiator.prototype.encodings;
 | |
| Negotiator.prototype.preferredLanguage = Negotiator.prototype.language;
 | |
| Negotiator.prototype.preferredLanguages = Negotiator.prototype.languages;
 | |
| Negotiator.prototype.preferredMediaType = Negotiator.prototype.mediaType;
 | |
| Negotiator.prototype.preferredMediaTypes = Negotiator.prototype.mediaTypes;
 | |
| 
 | |
| /**
 | |
|  * Load the given module.
 | |
|  * @private
 | |
|  */
 | |
| 
 | |
| function loadModule(moduleName) {
 | |
|   var module = modules[moduleName];
 | |
| 
 | |
|   if (module !== undefined) {
 | |
|     return module;
 | |
|   }
 | |
| 
 | |
|   // This uses a switch for static require analysis
 | |
|   switch (moduleName) {
 | |
|     case 'charset':
 | |
|       module = require('./lib/charset');
 | |
|       break;
 | |
|     case 'encoding':
 | |
|       module = require('./lib/encoding');
 | |
|       break;
 | |
|     case 'language':
 | |
|       module = require('./lib/language');
 | |
|       break;
 | |
|     case 'mediaType':
 | |
|       module = require('./lib/mediaType');
 | |
|       break;
 | |
|     default:
 | |
|       throw new Error('Cannot find module \'' + moduleName + '\'');
 | |
|   }
 | |
| 
 | |
|   // Store to prevent invoking require()
 | |
|   modules[moduleName] = module;
 | |
| 
 | |
|   return module;
 | |
| }
 |