twitst4tz

index.js (4416B)

---

 
 /*!
  *  Copyright 2010 LearnBoost <dev@learnboost.com>
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 
 /**
  * Module dependencies.
  */
 
 var crypto = require('crypto')
   , parse = require('url').parse
   ;
 
 /**
  * Valid keys.
  */
 
 var keys = 
   [ 'acl'
   , 'location'
   , 'logging'
   , 'notification'
   , 'partNumber'
   , 'policy'
   , 'requestPayment'
   , 'torrent'
   , 'uploadId'
   , 'uploads'
   , 'versionId'
   , 'versioning'
   , 'versions'
   , 'website'
   ]
 
 /**
  * Return an "Authorization" header value with the given `options`
  * in the form of "AWS <key>:<signature>"
  *
  * @param {Object} options
  * @return {String}
  * @api private
  */
 
 function authorization (options) {
   return 'AWS ' + options.key + ':' + sign(options)
 }
 
 module.exports = authorization
 module.exports.authorization = authorization
 
 /**
  * Simple HMAC-SHA1 Wrapper
  *
  * @param {Object} options
  * @return {String}
  * @api private
  */ 
 
 function hmacSha1 (options) {
   return crypto.createHmac('sha1', options.secret).update(options.message).digest('base64')
 }
 
 module.exports.hmacSha1 = hmacSha1
 
 /**
  * Create a base64 sha1 HMAC for `options`. 
  * 
  * @param {Object} options
  * @return {String}
  * @api private
  */
 
 function sign (options) {
   options.message = stringToSign(options)
   return hmacSha1(options)
 }
 module.exports.sign = sign
 
 /**
  * Create a base64 sha1 HMAC for `options`. 
  *
  * Specifically to be used with S3 presigned URLs
  * 
  * @param {Object} options
  * @return {String}
  * @api private
  */
 
 function signQuery (options) {
   options.message = queryStringToSign(options)
   return hmacSha1(options)
 }
 module.exports.signQuery= signQuery
 
 /**
  * Return a string for sign() with the given `options`.
  *
  * Spec:
  * 
  *    <verb>\n
  *    <md5>\n
  *    <content-type>\n
  *    <date>\n
  *    [headers\n]
  *    <resource>
  *
  * @param {Object} options
  * @return {String}
  * @api private
  */
 
 function stringToSign (options) {
   var headers = options.amazonHeaders || ''
   if (headers) headers += '\n'
   var r = 
     [ options.verb
     , options.md5
     , options.contentType
     , options.date ? options.date.toUTCString() : ''
     , headers + options.resource
     ]
   return r.join('\n')
 }
 module.exports.stringToSign = stringToSign
 
 /**
  * Return a string for sign() with the given `options`, but is meant exclusively
  * for S3 presigned URLs
  *
  * Spec:
  * 
  *    <date>\n
  *    <resource>
  *
  * @param {Object} options
  * @return {String}
  * @api private
  */
 
 function queryStringToSign (options){
   return 'GET\n\n\n' + options.date + '\n' + options.resource
 }
 module.exports.queryStringToSign = queryStringToSign
 
 /**
  * Perform the following:
  *
  *  - ignore non-amazon headers
  *  - lowercase fields
  *  - sort lexicographically
  *  - trim whitespace between ":"
  *  - join with newline
  *
  * @param {Object} headers
  * @return {String}
  * @api private
  */
 
 function canonicalizeHeaders (headers) {
   var buf = []
     , fields = Object.keys(headers)
     ;
   for (var i = 0, len = fields.length; i < len; ++i) {
     var field = fields[i]
       , val = headers[field]
       , field = field.toLowerCase()
       ;
     if (0 !== field.indexOf('x-amz')) continue
     buf.push(field + ':' + val)
   }
   return buf.sort().join('\n')
 }
 module.exports.canonicalizeHeaders = canonicalizeHeaders
 
 /**
  * Perform the following:
  *
  *  - ignore non sub-resources
  *  - sort lexicographically
  *
  * @param {String} resource
  * @return {String}
  * @api private
  */
 
 function canonicalizeResource (resource) {
   var url = parse(resource, true)
     , path = url.pathname
     , buf = []
     ;
 
   Object.keys(url.query).forEach(function(key){
     if (!~keys.indexOf(key)) return
     var val = '' == url.query[key] ? '' : '=' + encodeURIComponent(url.query[key])
     buf.push(key + val)
   })
 
   return path + (buf.length ? '?' + buf.sort().join('&') : '')
 }
 module.exports.canonicalizeResource = canonicalizeResource