1  /*!
  2   * statuses
  3   * Copyright(c) 2014 Jonathan Ong
  4   * Copyright(c) 2016 Douglas Christopher Wilson
  5   * MIT Licensed
  6   */
  7  
  8  'use strict'
  9  
 10  /**
 11   * Module dependencies.
 12   * @private
 13   */
 14  
 15  var codes = require('./codes.json')
 16  
 17  /**
 18   * Module exports.
 19   * @public
 20   */
 21  
 22  module.exports = status
 23  
 24  // status code to message map
 25  status.message = codes
 26  
 27  // status message (lower-case) to code map
 28  status.code = createMessageToStatusCodeMap(codes)
 29  
 30  // array of status codes
 31  status.codes = createStatusCodeList(codes)
 32  
 33  // status codes for redirects
 34  status.redirect = {
 35    300: true,
 36    301: true,
 37    302: true,
 38    303: true,
 39    305: true,
 40    307: true,
 41    308: true
 42  }
 43  
 44  // status codes for empty bodies
 45  status.empty = {
 46    204: true,
 47    205: true,
 48    304: true
 49  }
 50  
 51  // status codes for when you should retry the request
 52  status.retry = {
 53    502: true,
 54    503: true,
 55    504: true
 56  }
 57  
 58  /**
 59   * Create a map of message to status code.
 60   * @private
 61   */
 62  
 63  function createMessageToStatusCodeMap (codes) {
 64    var map = {}
 65  
 66    Object.keys(codes).forEach(function forEachCode (code) {
 67      var message = codes[code]
 68      var status = Number(code)
 69  
 70      // populate map
 71      map[message.toLowerCase()] = status
 72    })
 73  
 74    return map
 75  }
 76  
 77  /**
 78   * Create a list of all status codes.
 79   * @private
 80   */
 81  
 82  function createStatusCodeList (codes) {
 83    return Object.keys(codes).map(function mapCode (code) {
 84      return Number(code)
 85    })
 86  }
 87  
 88  /**
 89   * Get the status code for given message.
 90   * @private
 91   */
 92  
 93  function getStatusCode (message) {
 94    var msg = message.toLowerCase()
 95  
 96    if (!Object.prototype.hasOwnProperty.call(status.code, msg)) {
 97      throw new Error('invalid status message: "' + message + '"')
 98    }
 99  
100    return status.code[msg]
101  }
102  
103  /**
104   * Get the status message for given code.
105   * @private
106   */
107  
108  function getStatusMessage (code) {
109    if (!Object.prototype.hasOwnProperty.call(status.message, code)) {
110      throw new Error('invalid status code: ' + code)
111    }
112  
113    return status.message[code]
114  }
115  
116  /**
117   * Get the status code.
118   *
119   * Given a number, this will throw if it is not a known status
120   * code, otherwise the code will be returned. Given a string,
121   * the string will be parsed for a number and return the code
122   * if valid, otherwise will lookup the code assuming this is
123   * the status message.
124   *
125   * @param {string|number} code
126   * @returns {number}
127   * @public
128   */
129  
130  function status (code) {
131    if (typeof code === 'number') {
132      return getStatusMessage(code)
133    }
134  
135    if (typeof code !== 'string') {
136      throw new TypeError('code must be a number or string')
137    }
138  
139    // '403'
140    var n = parseInt(code, 10)
141    if (!isNaN(n)) {
142      return getStatusMessage(n)
143    }
144  
145    return getStatusCode(code)
146  }