Feed Fetcher

FeedFetcher is a plugin to help you to locate feeds. Currently it only locates RSS feeds. FeedFetcher can be supplied with a URL and a RSS object will be populated from that URL, if the URL represents either a RSS resource, or a HTML resource that contains a link to a RSS page in head tag.

This enables you to provide a nice simple “add feed” function to any site that aggregates RSS feeds where the user doesn’t necessarily know the difference between a blog web page and a blog feed. They can just enter either, and feed fetcher will figure it out.

Credits

By Craig Ambrose craig@craigambrose.com

Up to date details on this plugin located at: http://www.craigambrose.com/projects/feed_fetcher

Licence

MIT License

http://www.opensource.org/licenses/mit-license.php

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so.

Installation

script/plugin install svn://rubyforge.org/var/svn/ambroseplugins/redbox

Usage

The main function that you’ll be using is the class method get_feed_source on the FeedFetcher class. If successful, it’ll return a FeedSource object, that you can interrogate for the feed details or the items in the current feed. If it fails, it’ll throw an exception that you can use to determine the problem and return a message to the user.

Here’s the code that I use to call the feed fetcher from within my Blog model. If it works, I’m setting a couple of instance members on self.

begin result = FeedFetcher::FeedFetcher.get_feed_source(site_url) if result self.feed_url = result.url self.title = result.title end rescue FeedFetcher::NoFeedForPageError @feed_error = “Sorry, we couldn’t find a feed for this URL. Your blog needs to have a RSS feed facility for us to use it on Playful Bent.” rescue FeedFetcher::PageFeedError @feed_error = “You blog has a RSS feed, which is great. However, it doesn’t work for us right now, which is less great. Sorry, this wont work.” rescue FeedFetcher::PageDoesntExistError @feed_error = “Are you sure you typed that right? We just tried to fetch that URL and we couldn’t find anything there at all.” end