/vanilla-rss

An easy-to-use vanilla JavaScript library to read and render RSS feeds.

Primary LanguageJavaScriptMIT LicenseMIT

vanilla-rss Build Status npm version npm

An easy-to-use vanilla JavaScript library to read and render RSS feeds.

Support

Users of jquery.rss, vanilla-rss or feedr have the chance to support funding future developments and covering the costs for the hosting of the RSS lib respective server side companion app feedr.

Every once in a while supporters will get affiliate links instead of one of the feed's entries.

If you are not interested in supporting the authors of the plugin, then you can easily opt-out of it by setting the respective support option. See below for further details.

Thanks in advance!

Installation

Through npm:

$ npm install vanilla-rss
const RSS = require('vanilla-rss');
const rss = new RSS(
    document.querySelector("#rss-feeds"),
    "https://partnernetwork.ebay.de/epn-blog?format=rss",
    {}
);
rss.render();

Through cdnjs:

https://cdnjs.cloudflare.com/ajax/libs/jquery-rss/4.3.0/jquery.rss.min.js

Setup

<!DOCTYPE html>
<html>
  <head>
    <title>RSS Example</title>
    <script src="dist/rss.global.min.js"></script>
    <script>
      window.onload = function() {
        new RSS(
          document.querySelector("#rss-feeds"),
          "https://partnernetwork.ebay.de/epn-blog?format=rss"
        ).render();
      };
    </script>
  </head>
  <body>
    <div id="rss-feeds"></div>
  </body>
</html>

Demo link for above code: http://embed.plnkr.co/WQRoCYLld162uplnz1rc/preview

Note: Moment.js is optional. If you include it, vanilla-rss will use it to format dates. If you do not want to include Moment.js, you may opt for providing your own date formatting function, or for not formatting dates at all.

Options

const rss = new RSS(document.querySelector('#rss'), "https://jsfeeds.com/feed", {
  // how many entries do you want?
  // default: 4
  // valid values: any integer
  limit: 10,

  // want to offset results being displayed?
  // default: false
  // valid values: any integer
  offsetStart: false, // offset start point
  offsetEnd: false, // offset end point

  // will request the API via https
  // default: false
  // valid values: false, true
  ssl: true,

  // which server should be requested for feed parsing
  // the server implementation is here: https://github.com/sdepold/feedr
  // default: feedrapp.info
  // valid values: any string
  host: 'my-own-feedr-instance.com',

  // option to seldomly render ads
  // ads help covering the costs for the feedrapp server hosting and future improvements
  // default: true
  // valid values: false, true
  support: false,

  // outer template for the html transformation
  // default: "<ul>{entries}</ul>"
  // valid values: any string
  layoutTemplate: "<div class='feed-container'>{entries}</div>",

  // inner template for each entry
  // default: '<li><a href="{url}">[{author}@{date}] {title}</a><br/>{shortBodyPlain}</li>'
  // valid values: any string
  entryTemplate: '<p>{title}</p>',

  // additional token definition for in-template-usage
  // default: {}
  // valid values: any object/hash
  tokens: {
    foo: 'bar',
    bar: function(entry, tokens) { return entry.title }
  },

  // formats the date with moment.js (optional)
  // default: 'dddd MMM Do'
  // valid values: see http://momentjs.com/docs/#/displaying/
  dateFormat: 'MMMM Do, YYYY',

  // localizes the date with moment.js (optional)
  // default: 'en'
  dateLocale: 'de',

  // formats the date in whatever manner you choose. (optional)
  // this function should return your formatted date.
  // this is useful if you want to format dates without moment.js.
  // if you don't use moment.js and don't define a dateFormatFunction, the dates will
  // not be formatted; they will appear exactly as the RSS feed gives them to you.
  dateFormatFunction: function(date){},

  // Defines the format which is used for the feed.
  // Default: null (utf8)
  // valid values: https://github.com/ashtuchkin/iconv-lite/wiki/Supported-Encodings
  encoding: 'ISO-8859-1 ',

  // Defined the order of the feed's entries.
  // Default: undefined (keeps the order of the original feed)
  // valid values: All entry properties; title, link, content, contentSnippet, publishedDate, categories, author, thumbnail
  // Order can be reversed by prefixing a dash (-)
  order: '-publishedDate',

  fetchFeed: (apiUrl) => {
    return new Promise((resolve) => {
      $.getJSON(apiUrl, resolve);
    });
  }
});

rss

  // An observer which gets triggered once data was received but before the rendering.
  .on('data', (data) => {
    console.log(data.rss); // Returns the rss instance
    console.log(data.feed); // Returns the feed meta information
    console.log(data.entries); // Returns the feed entries
  })

  // Parse the RSS feed and render it accordingly to the configured layout and entry template.
  // The render call returns a promise.
  .render()

  .then(
    // A callback, which gets triggered when every entry was loaded and rendered successfully
    ()=>{},

    // A callback, which gets triggered when an error occurs
    (e)=>{}
  );

Note about the host option

This library is using a Google Feed API drop-in replacement called feedr. The server is hosted on a central public server and each time this plugin loads, the server is parsing the XML feed and returning the respective JSON representation.

If you don't want to rely on the provided server and instead run your own version, you can just download feedr, install the dependencies and run it. As written above, you can specify the host which is used to parse the feeds with the host option.

Templating

As seen in the options, you can specify a template in order to transform the json objects into HTML. In order to that, you can either define the outer template (which describes the html around the entries) or the entry template (which describes the html of an entry).

The basic format of those templates are:

# layoutTemplate:
"<outer-html>{entries}</outer-html>"

# entryTemplate:
"<any-html>{token1}{token2}</any-html>"

So, let's say you have specified a limit of 2, using the upper pseudo html. This will result in the following:

<outer-html>
  <any-html>{token1}{token2}</any-html>
  <any-html>{token1}{token2}</any-html>
</outer-html>

There are some predefined tokens:

  • url: the url to the post
  • author: the author of the post
  • date: the publishing date
  • title: the title of the post
  • body: the complete content of the post
  • shortBody: the shortened content of the post
  • bodyPlain: the complete content of the post without html
  • shortBodyPlain: the shortened content of the post without html
  • teaserImage: the first image in the post's body
  • teaserImageUrl: the url of the first image in the post's body
  • index: the index of the current entry
  • totalEntries: the total count of the entries
  • feed: contains high level information of the feed (e.g. title of the website)

You can also define custom tokens using the tokens option:

new RSS(document.querySelector('#rss'), url, {
  entryTemplate: "{dynamic}, {static}, {re-use}",
  tokens: {
    dynamic: function(entry, tokens){ return "dynamic-stuff: " + entry.title },
    "re-use": function(entry, tokens){ return encodeURIComponent(tokens.teaserImageUrl) },
    static: "static"
  }
}).render();

Please make sure to NOT define infinite loops. The following example is really BAD:

new RSS(document.querySelector('#rss'), url, {
  entryTemplate: "{loop}",
  tokens: {
    whoops: function(entry, tokens) { return tokens.loop() }
    loop: function(entry, tokens) { return tokens.whoops() }
  }
}).render();

Here is a real-world example:

new RSS(document.querySelector('#rss'), url, {
  layoutTemplate: "<table><tr><th>Title</th></tr>{entries}</table>",
  entryTemplate:  "<tr><td>{title}</td></tr>"
}).render();

Filtering

The plugin also allows you to filter specific entries in order to only print them:

new RSS(document.querySelector('#rss'), url, {
  limit: 100,
  filterLimit: 10,
  filter: function(entry, tokens) {
    return tokens.title.indexOf('my filter') > -1
  }
}).render();

This will request 100 entries via the Feed API and renders the first 10 matching entries.

Multiple feed URLs

It is also possible to provide several feed URLs separated by commas. Please note, that this feature is experimental and might change in the future!

new RSS(document.querySelector('#rss'), ['url1', 'url2', 'urlN']).render();

The Feedr server will now query all of the provided feeds and append all entries to the first feed.

Authors/Contributors