Saturday, March 08, 2008

rAtom 0.2.1 Gem released

rAtom is a Ruby Gem for working with the Atom Syndication Format and the Atom Publishing Protocol (APP).

rAtom was originally built to support the communication between a number of applications built by Peerworks[http://peerworks.org], via the Atom Publishing protocol. However, it supports, or aims to support, all the Atom Syndication Format and Publication Protocol and can be used to access Atom feeds or to script publishing entries to a blog supporting APP.

Features:
  • Uses libxml-ruby so it is _much_ faster than a REXML based library.
  • Uses the libxml pull parser so it has much lighter memory usage.
  • Supports RFC 5005 (http://www.ietf.org/rfc/rfc5005.txt) for feed pagination.

You can install via gem using:
# sudo gem install ratom

Usage

To fetch and parse an Atom Feed you can simply:
feed = Atom::Feed.load_feed(URI.parse("http://example.com/feed.atom"))

And then iterate over the entries in the feed using:

feed.each_entry do |entry|
# do cool stuff
end

To construct a Feed

feed = Atom::Feed.new do |feed|
feed.title = "My Cool Feed"
feed.id = "http://example.com/my_feed.atom"
feed.updated = Time.now
end

To output a Feed as XML use to_xml

> puts feed.to_xml
<feed xmlns="http://www.w3.org/2005/Atom">
<title>My Cool Feed</title>
<id>http://example.com/my_feed.atom</id>
<updated>2008-03-03T23:19:44+10:30</updated>
</feed>

Publishing

To publish to a remote feed using the Atom Publishing Protocol, first you need to create a collection to publish to:
collection = Atom::Pub::Collection.new(:href => 'http://example.org/myblog')

Then create a new entry:
entry = Atom::Entry.new do |entry|
entry.title = "I have discovered rAtom"
entry.authors << name =""> 'A happy developer')
entry.updated = Time.now
entry.id = "http://example.org/myblog/newpost"
entry.content = Atom::Content::Html.new("<p>rAtom lets me post to my blog using Ruby, how cool!</p>")
end

And publish it to the Collection:
published_entry = collection.publish(entry)

More Information

See http://ratom.rubyforge.org for more information.