RSS Finder

A simple web component finding RSS feeds for different sources.

Intended embedded use cases:

Use Case	Embed Type	Used by
Progressive web app RSS reader	web component	lzone.de
Native RSS app with browser widget	website	Liferea
Native RSS app without browser widget	launch in default browser

Embed as website

In a native app open a HTML widget and launch the URL

https://lwindolf.github.io/rss-finder?show-title=false

If possible do disable CORS, if it is not possible enable the CORS proxy by adding use-cors-proxy=true to the query string.

If your app does not feed: as protocol handler set a scheme value in the query string.

If your app does not have a browser widget you can still provide a menu option like "Discover Feeds" and open the the RSS Finder URL using Linux xdg-open or the corresponding GUI toolkit method to launch RSS Finder in the users default browser. Your app will receive the subscribed feed URLs via the defined URI scheme.

Embed as a web component

1. npm run build

2. Copy the www directory to your code base as rss-finder

3. Include the sources

   <script src="rss-finder/js/vendor/handlebars.min.js"></script>
   <script type="module" src="rss-finder/js/widget.js"></script>
   

4. Use the custom HTML element in your web app.

   <x-rss-finder icons="rss-finder/icons" subscribe-method="event" use-cors-proxy="true">
   

5. Register an subscribe event handler

   document.querySelector('x-rss-finder').addEventListener('rss-finder-subscribe', (ev) => {
      alert(`Subscribing to feed URL ${ev.detail.url}`);
   });
   

Note: due to "web+" custom protocol handlers not working together with CSP and CORS when used as a web component subscribe-method needs to be event.

Configuration Parameters

Configuration parameters are to be passed by query string for iframe embedding or by by attribute when including as web component. The following parameters are supported:

Parameter	Description	Default
show-title	Whether to add a <h1> title	true
icon-path	Path to subscriber icons (adapt it when using as webcomponent)	icons
scheme	Which URI scheme to trigger for subscriptions	feed:
use-cors-proxy	Whether to retry using a CORS proxy when a network error occurs	false
cors-proxy	URL of a cors proxy to use	https://corsproxy.io/?url=
subscribe-method	How to subscribe (via location using the define schema or via event)	location

Privacy considerations

CORS proxy

Per default use-cors-proxy is disabled, so everything happens at the user side. This is ok for e.g. Electron apps or native apps with embedded browser widgets which can disable CORS internally.

If you want to use RSS finder in a pure web app the browser CORS settings will disallow access to almost all feeds and you will need to enable the cors-proxy. In this case ensure your users know about the privacy impact (e.g. Cloudflare hosting corsproxy.io potentially knowing about the feeds they subscribe to).

Accessing 3rd party APIs

Some subscriber access 3rd party APIs:

• iTunes
• Mastodon
• BlueSky
• Lemmy

Any search will be exposed to those providers.