twitst4tz

twitter statistics web application
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index.js (3344B)

      1 /*!
      2  * negotiator
      3  * Copyright(c) 2012 Federico Romero
      4  * Copyright(c) 2012-2014 Isaac Z. Schlueter
      5  * Copyright(c) 2015 Douglas Christopher Wilson
      6  * MIT Licensed
      7  */
      8 
      9 'use strict';
     10 
     11 /**
     12  * Cached loaded submodules.
     13  * @private
     14  */
     15 
     16 var modules = Object.create(null);
     17 
     18 /**
     19  * Module exports.
     20  * @public
     21  */
     22 
     23 module.exports = Negotiator;
     24 module.exports.Negotiator = Negotiator;
     25 
     26 /**
     27  * Create a Negotiator instance from a request.
     28  * @param {object} request
     29  * @public
     30  */
     31 
     32 function Negotiator(request) {
     33   if (!(this instanceof Negotiator)) {
     34     return new Negotiator(request);
     35   }
     36 
     37   this.request = request;
     38 }
     39 
     40 Negotiator.prototype.charset = function charset(available) {
     41   var set = this.charsets(available);
     42   return set && set[0];
     43 };
     44 
     45 Negotiator.prototype.charsets = function charsets(available) {
     46   var preferredCharsets = loadModule('charset').preferredCharsets;
     47   return preferredCharsets(this.request.headers['accept-charset'], available);
     48 };
     49 
     50 Negotiator.prototype.encoding = function encoding(available) {
     51   var set = this.encodings(available);
     52   return set && set[0];
     53 };
     54 
     55 Negotiator.prototype.encodings = function encodings(available) {
     56   var preferredEncodings = loadModule('encoding').preferredEncodings;
     57   return preferredEncodings(this.request.headers['accept-encoding'], available);
     58 };
     59 
     60 Negotiator.prototype.language = function language(available) {
     61   var set = this.languages(available);
     62   return set && set[0];
     63 };
     64 
     65 Negotiator.prototype.languages = function languages(available) {
     66   var preferredLanguages = loadModule('language').preferredLanguages;
     67   return preferredLanguages(this.request.headers['accept-language'], available);
     68 };
     69 
     70 Negotiator.prototype.mediaType = function mediaType(available) {
     71   var set = this.mediaTypes(available);
     72   return set && set[0];
     73 };
     74 
     75 Negotiator.prototype.mediaTypes = function mediaTypes(available) {
     76   var preferredMediaTypes = loadModule('mediaType').preferredMediaTypes;
     77   return preferredMediaTypes(this.request.headers.accept, available);
     78 };
     79 
     80 // Backwards compatibility
     81 Negotiator.prototype.preferredCharset = Negotiator.prototype.charset;
     82 Negotiator.prototype.preferredCharsets = Negotiator.prototype.charsets;
     83 Negotiator.prototype.preferredEncoding = Negotiator.prototype.encoding;
     84 Negotiator.prototype.preferredEncodings = Negotiator.prototype.encodings;
     85 Negotiator.prototype.preferredLanguage = Negotiator.prototype.language;
     86 Negotiator.prototype.preferredLanguages = Negotiator.prototype.languages;
     87 Negotiator.prototype.preferredMediaType = Negotiator.prototype.mediaType;
     88 Negotiator.prototype.preferredMediaTypes = Negotiator.prototype.mediaTypes;
     89 
     90 /**
     91  * Load the given module.
     92  * @private
     93  */
     94 
     95 function loadModule(moduleName) {
     96   var module = modules[moduleName];
     97 
     98   if (module !== undefined) {
     99     return module;
    100   }
    101 
    102   // This uses a switch for static require analysis
    103   switch (moduleName) {
    104     case 'charset':
    105       module = require('./lib/charset');
    106       break;
    107     case 'encoding':
    108       module = require('./lib/encoding');
    109       break;
    110     case 'language':
    111       module = require('./lib/language');
    112       break;
    113     case 'mediaType':
    114       module = require('./lib/mediaType');
    115       break;
    116     default:
    117       throw new Error('Cannot find module \'' + moduleName + '\'');
    118   }
    119 
    120   // Store to prevent invoking require()
    121   modules[moduleName] = module;
    122 
    123   return module;
    124 }