index.js

var Entities = require("entities");
var FS = require('fs');
var XML2JS = require('xml2js');

var HTTP = require('http');
var HTTPS = require('https');

var Parser = module.exports = {};

var TOP_FIELDS = ['title', 'description', 'author', 'link'];
var ITEM_FIELDS = [
  'title',
  'link',
  'pubDate',
  'author',
]

var stripHtml = function(str) {
  return str.replace(/<(?:.|\n)*?>/gm, '');
}

var parseRSS1 = function(xmlObj, callback) {
  callback("RSS 1.0 parsing not yet implemented.")
}

var parseRSS2 = function(xmlObj, callback) {
  var json = {feed: {entries: []}};
  var channel = xmlObj.rss.channel[0];
  if (channel['atom:link']) json.feed.feedUrl = channel['atom:link'][0].href;
  TOP_FIELDS.forEach(function(f) {
    if (channel[f]) json.feed[f] = channel[f][0];
  })
  var items = channel.item;
  (items || []).forEach(function(item) {
    var entry = {};
    ITEM_FIELDS.forEach(function(f) {
      if (item[f]) entry[f] = item[f][0];
    })
    if (item.description) {
      entry.content = item.description[0];
      entry.contentSnippet = entry.content;
      //entry.contentSnippet = Entities.decode(stripHtml(entry.content));
    }
    if (item.guid) {
      entry.guid = item.guid[0]._;
    }
    if (item.category) entry.categories = item.category;
    json.feed.entries.push(entry);
  })
  callback(null, json);
}

Parser.parseString = function(xml, callback) {
  XML2JS.parseString(xml, function(err, result) {
    if (err) throw err;
    if (result.rss && result.rss.$.version && result.rss.$.version.indexOf('2') === 0) return parseRSS2(result, callback);
    else return parseRSS1(result, callback);
  });
}

Parser.parseURL = function(url, callback) {
  var xml = '';
  var get = url.indexOf('https') === 0 ? HTTPS.get : HTTP.get;
  var req = get(url, function(res) {
    if (res.statusCode >= 300) return callback(new Error("Status code " + res.statusCode))
    res.setEncoding('utf8');
    res.on('data', function(chunk) {
      xml += chunk;
    });
    res.on('end', function() {
      return Parser.parseString(xml, callback);
    })
  })
  req.on('error', callback);
}

Parser.parseFile = function(file, callback) {
  FS.readFile(file, 'utf8', function(err, contents) {
    return Parser.parseString(contents, callback);
  })
}