@cao-mei-you-ren/rss-parser

rss-parser

A small library for turning RSS XML feeds into JavaScript objects.

Installation

npm install --save rss-parser

Usage

You can parse RSS from a URL (parser.parseURL) or an XML string (parser.parseString).

Both callbacks and Promises are supported.

NodeJS

Here's an example in NodeJS using Promises with async/await:

let Parser = require('rss-parser');
let parser = new Parser();

(async () => {

  let feed = await parser.parseURL('https://www.reddit.com/.rss');
  console.log(feed.title);

  feed.items.forEach(item => {
    console.log(item.title + ':' + item.link)
  });

})();

TypeScript

When using TypeScript, you can set a type to control the custom fields:

import Parser from 'rss-parser';

type CustomFeed = {foo: string};
type CustomItem = {bar: number};

const parser: Parser<CustomFeed, CustomItem> = new Parser({
  customFields: {
    feed: ['foo', 'baz'],
    //            ^ will error because `baz` is not a key of CustomFeed
    item: ['bar']
  }
});

(async () => {
  const parser = new Parser();
  const feed = await parser.parseURL('https://www.reddit.com/.rss');
  console.log(feed.title); // feed will have a `foo` property, type as a string

  feed.items.forEach(item => {
    console.log(item.title + ':' + item.link) // item will have a `bar` property type as a number
  });
})();

Web

We recommend using a bundler like webpack, but we also provide pre-built browser distributions in the dist/ folder. If you use the pre-built distribution, you'll need a polyfill for Promise support.

Here's an example in the browser using callbacks:

<script src="/node_modules/rss-parser/dist/rss-parser.min.js"></script>
<script>

// Note: some RSS feeds can't be loaded in the browser due to CORS security.
// To get around this, you can use a proxy.
const CORS_PROXY = "https://cors-anywhere.herokuapp.com/"

let parser = new RSSParser();
parser.parseURL(CORS_PROXY + 'https://www.reddit.com/.rss', function(err, feed) {
  if (err) throw err;
  console.log(feed.title);
  feed.items.forEach(function(entry) {
    console.log(entry.title + ':' + entry.link);
  })
})

</script>

Upgrading from v2 to v3

A few minor breaking changes were made in v3. Here's what you need to know:

• You need to construct a new Parser() before calling parseString or parseURL
• parseFile is no longer available (for better browser support)
• options are now passed to the Parser constructor
• parsed.feed is now just feed (top-level object removed)
• feed.entries is now feed.items (to better match RSS XML)

Output

Check out the full output format in test/output/reddit.json

feedUrl: 'https://www.reddit.com/.rss'
title: 'reddit: the front page of the internet'
description: ""
link: 'https://www.reddit.com/'
items:
    - title: 'The water is too deep, so he improvises'
      link: 'https://www.reddit.com/r/funny/comments/3skxqc/the_water_is_too_deep_so_he_improvises/'
      pubDate: 'Thu, 12 Nov 2015 21:16:39 +0000'
      creator: "John Doe"
      content: '<a href="http://example.com">this is a link</a> &amp; <b>this is bold text</b>'
      contentSnippet: 'this is a link & this is bold text'
      guid: 'https://www.reddit.com/r/funny/comments/3skxqc/the_water_is_too_deep_so_he_improvises/'
      categories:
          - funny
      isoDate: '2015-11-12T21:16:39.000Z'

Notes:

• The contentSnippet field strips out HTML tags and unescapes HTML entities
• The dc: prefix will be removed from all fields
• Both dc:date and pubDate will be available in ISO 8601 format as isoDate
• If author is specified, but not dc:creator, creator will be set to author (see article)
• Atom's updated becomes lastBuildDate for consistency

XML Options

Custom Fields

If your RSS feed contains fields that aren't currently returned, you can access them using the customFields option.

let parser = new Parser({
  customFields: {
    feed: ['otherTitle', 'extendedDescription'],
    item: ['coAuthor','subtitle'],
  }
});

parser.parseURL('https://www.reddit.com/.rss', function(err, feed) {
  console.log(feed.extendedDescription);

  feed.items.forEach(function(entry) {
    console.log(entry.coAuthor + ':' + entry.subtitle);
  })
})

To rename fields, you can pass in an array with two items, in the format [fromField, toField]:

let parser = new Parser({
  customFields: {
    item: [
      ['dc:coAuthor', 'coAuthor'],
    ]
  }
})

To pass additional flags, provide an object as the third array item. Currently there is one such flag:

• keepArray (false) - set to true to return all values for fields that can have multiple entries.
• includeSnippet (false) - set to true to add an additional field, ${toField}Snippet, with HTML stripped out

let parser = new Parser({
  customFields: {
    item: [
      ['media:content', 'media:content', {keepArray: true}],
    ]
  }
})

Default RSS version

If your RSS Feed doesn't contain a <rss> tag with a version attribute, you can pass a defaultRSS option for the Parser to use:

let parser = new Parser({
  defaultRSS: 2.0
});

xml2js passthrough

rss-parser uses xml2js to parse XML. You can pass these options to new xml2js.Parser() by specifying options.xml2js:

let parser = new Parser({
  xml2js: {
    emptyTag: '--EMPTY--',
  }
});

HTTP Options

Timeout

You can set the amount of time (in milliseconds) to wait before the HTTP request times out (default 60 seconds):

let parser = new Parser({
  timeout: 1000,
});

Headers

You can pass headers to the HTTP request:

let parser = new Parser({
  headers: {'User-Agent': 'something different'},
});

Redirects

By default, parseURL will follow up to five redirects. You can change this with options.maxRedirects.

let parser = new Parser({maxRedirects: 100});

Request passthrough

rss-parser uses http/https module to do requests. You can pass these options to http.get()/https.get() by specifying options.requestOptions:

e.g. to allow unauthorized certificate

let parser = new Parser({
  requestOptions: {
    rejectUnauthorized: false
  }
});

Contributing

Contributions are welcome! If you are adding a feature or fixing a bug, please be sure to add a test case

Running Tests

The tests run the RSS parser for several sample RSS feeds in test/input and outputs the resulting JSON into test/output. If there are any changes to the output files the tests will fail.

To check if your changes affect the output of any test cases, run

npm test

To update the output files with your changes, run

WRITE_GOLDEN=true npm test

Publishing Releases

npm run build
git commit -a -m "Build distribution"
npm version minor # or major/patch
npm publish
git push --follow-tags