HarshvardhanCn01/Voice-Assistant

1/*!2 * forwarded3 * Copyright(c) 2014-2017 Douglas Christopher Wilson4 * MIT Licensed5 */6 7'use strict'8 9/**10 * Module exports.11 * @public12 */13 14module.exports = forwarded15 16/**17 * Get all addresses in the request, using the `X-Forwarded-For` header.18 *19 * @param {object} req20 * @return {array}21 * @public22 */23 24function forwarded (req) {25  if (!req) {26    throw new TypeError('argument req is required')27  }28 29  // simple header parsing30  var proxyAddrs = parse(req.headers['x-forwarded-for'] || '')31  var socketAddr = getSocketAddr(req)32  var addrs = [socketAddr].concat(proxyAddrs)33 34  // return all addresses35  return addrs36}37 38/**39 * Get the socket address for a request.40 *41 * @param {object} req42 * @return {string}43 * @private44 */45 46function getSocketAddr (req) {47  return req.socket48    ? req.socket.remoteAddress49    : req.connection.remoteAddress50}51 52/**53 * Parse the X-Forwarded-For header.54 *55 * @param {string} header56 * @private57 */58 59function parse (header) {60  var end = header.length61  var list = []62  var start = header.length63 64  // gather addresses, backwards65  for (var i = header.length - 1; i >= 0; i--) {66    switch (header.charCodeAt(i)) {67      case 0x20: /*   */68        if (start === end) {69          start = end = i70        }71        break72      case 0x2c: /* , */73        if (start !== end) {74          list.push(header.substring(start, end))75        }76        start = end = i77        break78      default:79        start = i80        break81    }82  }83 84  // final address85  if (start !== end) {86    list.push(header.substring(start, end))87  }88 89  return list90}91