twitst4tz

index.js (4809B)

---

 /*!
  * content-type
  * Copyright(c) 2015 Douglas Christopher Wilson
  * MIT Licensed
  */
 
 'use strict'
 
 /**
  * RegExp to match *( ";" parameter ) in RFC 7231 sec 3.1.1.1
  *
  * parameter     = token "=" ( token / quoted-string )
  * token         = 1*tchar
  * tchar         = "!" / "#" / "$" / "%" / "&" / "'" / "*"
  *               / "+" / "-" / "." / "^" / "_" / "`" / "|" / "~"
  *               / DIGIT / ALPHA
  *               ; any VCHAR, except delimiters
  * quoted-string = DQUOTE *( qdtext / quoted-pair ) DQUOTE
  * qdtext        = HTAB / SP / %x21 / %x23-5B / %x5D-7E / obs-text
  * obs-text      = %x80-FF
  * quoted-pair   = "\" ( HTAB / SP / VCHAR / obs-text )
  */
 var PARAM_REGEXP = /; *([!#$%&'*+.^_`|~0-9A-Za-z-]+) *= *("(?:[\u000b\u0020\u0021\u0023-\u005b\u005d-\u007e\u0080-\u00ff]|\\[\u000b\u0020-\u00ff])*"|[!#$%&'*+.^_`|~0-9A-Za-z-]+) */g
 var TEXT_REGEXP = /^[\u000b\u0020-\u007e\u0080-\u00ff]+$/
 var TOKEN_REGEXP = /^[!#$%&'*+.^_`|~0-9A-Za-z-]+$/
 
 /**
  * RegExp to match quoted-pair in RFC 7230 sec 3.2.6
  *
  * quoted-pair = "\" ( HTAB / SP / VCHAR / obs-text )
  * obs-text    = %x80-FF
  */
 var QESC_REGEXP = /\\([\u000b\u0020-\u00ff])/g
 
 /**
  * RegExp to match chars that must be quoted-pair in RFC 7230 sec 3.2.6
  */
 var QUOTE_REGEXP = /([\\"])/g
 
 /**
  * RegExp to match type in RFC 7231 sec 3.1.1.1
  *
  * media-type = type "/" subtype
  * type       = token
  * subtype    = token
  */
 var TYPE_REGEXP = /^[!#$%&'*+.^_`|~0-9A-Za-z-]+\/[!#$%&'*+.^_`|~0-9A-Za-z-]+$/
 
 /**
  * Module exports.
  * @public
  */
 
 exports.format = format
 exports.parse = parse
 
 /**
  * Format object to media type.
  *
  * @param {object} obj
  * @return {string}
  * @public
  */
 
 function format (obj) {
   if (!obj || typeof obj !== 'object') {
     throw new TypeError('argument obj is required')
   }
 
   var parameters = obj.parameters
   var type = obj.type
 
   if (!type || !TYPE_REGEXP.test(type)) {
     throw new TypeError('invalid type')
   }
 
   var string = type
 
   // append parameters
   if (parameters && typeof parameters === 'object') {
     var param
     var params = Object.keys(parameters).sort()
 
     for (var i = 0; i < params.length; i++) {
       param = params[i]
 
       if (!TOKEN_REGEXP.test(param)) {
         throw new TypeError('invalid parameter name')
       }
 
       string += '; ' + param + '=' + qstring(parameters[param])
     }
   }
 
   return string
 }
 
 /**
  * Parse media type to object.
  *
  * @param {string|object} string
  * @return {Object}
  * @public
  */
 
 function parse (string) {
   if (!string) {
     throw new TypeError('argument string is required')
   }
 
   // support req/res-like objects as argument
   var header = typeof string === 'object'
     ? getcontenttype(string)
     : string
 
   if (typeof header !== 'string') {
     throw new TypeError('argument string is required to be a string')
   }
 
   var index = header.indexOf(';')
   var type = index !== -1
     ? header.substr(0, index).trim()
     : header.trim()
 
   if (!TYPE_REGEXP.test(type)) {
     throw new TypeError('invalid media type')
   }
 
   var obj = new ContentType(type.toLowerCase())
 
   // parse parameters
   if (index !== -1) {
     var key
     var match
     var value
 
     PARAM_REGEXP.lastIndex = index
 
     while ((match = PARAM_REGEXP.exec(header))) {
       if (match.index !== index) {
         throw new TypeError('invalid parameter format')
       }
 
       index += match[0].length
       key = match[1].toLowerCase()
       value = match[2]
 
       if (value[0] === '"') {
         // remove quotes and escapes
         value = value
           .substr(1, value.length - 2)
           .replace(QESC_REGEXP, '$1')
       }
 
       obj.parameters[key] = value
     }
 
     if (index !== header.length) {
       throw new TypeError('invalid parameter format')
     }
   }
 
   return obj
 }
 
 /**
  * Get content-type from req/res objects.
  *
  * @param {object}
  * @return {Object}
  * @private
  */
 
 function getcontenttype (obj) {
   var header
 
   if (typeof obj.getHeader === 'function') {
     // res-like
     header = obj.getHeader('content-type')
   } else if (typeof obj.headers === 'object') {
     // req-like
     header = obj.headers && obj.headers['content-type']
   }
 
   if (typeof header !== 'string') {
     throw new TypeError('content-type header is missing from object')
   }
 
   return header
 }
 
 /**
  * Quote a string if necessary.
  *
  * @param {string} val
  * @return {string}
  * @private
  */
 
 function qstring (val) {
   var str = String(val)
 
   // no need to quote tokens
   if (TOKEN_REGEXP.test(str)) {
     return str
   }
 
   if (str.length > 0 && !TEXT_REGEXP.test(str)) {
     throw new TypeError('invalid parameter value')
   }
 
   return '"' + str.replace(QUOTE_REGEXP, '\\$1') + '"'
 }
 
 /**
  * Class to represent a content type.
  * @private
  */
 function ContentType (type) {
   this.parameters = Object.create(null)
   this.type = type
 }