Xommelier is an XML Sommelier

Overview

Xommelier is an XML Object Mapper. You could describe some namespace (e.g. Atom) in ruby DSL and use it for parsing XML to Ruby objects or for building XML from Ruby objects.

Look into Xommelier::Atom, Xommelier::Atom::Threading, and Xommelier::Atom::History module for implementation of http://www.w3.org/2005/Atom namespace, Atom Threading, and Feed Paging and Archiving extensions

Project links

Examples with Atom

require 'xommelier/atom/full'

Reading a feed

feed = Xommelier::Atom::Feed.parse(open('spec/fixtures/feed.atom.xml'))
puts feed.id, feed.title, feed.updated

feed.entries do |entry|
  puts feed.id, feed.title, feed.published, feed.updated
  puts feed.content || feed.summary
end

Building a feed

feed = Xommelier::Atom::Feed.new
feed.id = 'http://example.com/blog'
feed.title = 'Example.com blog'
feed.complete = Xommelier::Atom::History::Complete.new

entry = feed.entry = Xommelier::Atom::Entry.new(
  id: 'http://example.com/blog/2012/03/05',
  title: "Happy Xommelier's day!",
  updated: 5.days.ago
).tap do |entry|
  entry.link = Xommelier::Atom::Link.new(
    href: entry.id,
    rel:  'alternate',
    type: 'text/html'
  )
  entry.links << Xommelier::Atom::Link.new(
    href:  "#{entry.id}/comments.atom",
    rel:   'replies',
    type:  'application/atom+xml',
    count: 5
  )
end

# Add Comments
3.times do |i|
  feed.entries << Xommelier::Atom::Entry.new(
    id: "http://example.com/blog/2012/03/05#comment_#{i}",
    title: ('Hooray! ' * (i + 1)).strip,
    updated: (5 - i).days.ago
  ).tap do |comment|
    comment.in_reply_to = Xommelier::Atom::Threading::InReplyTo.new(
      ref: entry.id,
      href: entry.link.href
    )
  end
end

puts feed.to_xml

will output:

<?xml version="1.0" encoding="utf-8"?>
<feed xmlns="http://www.w3.org/2005/Atom" xmlns:thr="http://purl.org/syndication/thread/1.0" xmlns:fh="http://purl.org/syndication/history/1.0">
  <id>http://example.com/blog</id>
  <title>Example.com blog</title>
  <fh:complete/>
  <entry>
    <id>http://example.com/blog/2012/03/05</id>
    <title>Happy Xommelier's day!</title>
    <updated>2012-02-29T07:52:51+04:00</updated>
    <link href="http://example.com/blog/2012/03/05" rel="alternate" type="text/html"/>
    <link href="http://example.com/blog/2012/03/05/comments.atom" rel="replies" type="application/atom+xml" thr:count="5"/>
  </entry>
  <entry>
    <id>http://example.com/blog/2012/03/05#comment_0</id>
    <title>Hooray!</title>
    <updated>2012-02-29T07:52:51+04:00</updated>
    <thr:in-reply-to ref="http://example.com/blog/2012/03/05" href="http://example.com/blog/2012/03/05"/>
  </entry>
  <entry>
    <id>http://example.com/blog/2012/03/05#comment_1</id>
    <title>Hooray! Hooray!</title>
    <updated>2012-03-01T07:52:51+04:00</updated>
    <thr:in-reply-to ref="http://example.com/blog/2012/03/05" href="http://example.com/blog/2012/03/05"/>
  </entry>
  <entry>
    <id>http://example.com/blog/2012/03/05#comment_2</id>
    <title>Hooray! Hooray! Hooray!</title>
    <updated>2012-03-02T07:52:51+04:00</updated>
    <thr:in-reply-to ref="http://example.com/blog/2012/03/05" href="http://example.com/blog/2012/03/05"/>
  </entry>
</feed>

Building from hash

feed = Xommelier::Atom::Feed.new(
  {
    title: 'Xommelier nest elements',
    subtitle: 'Xommelier is able to build complex objects from very nested hash',
    author: {name: 'Alexander', email: 'al@semyonov.us'},
    updated: Time.utc(2012, 04, 04, 04, 04),
    contributors: [
      {name: 'Ivan', email: 'ivan@example.com'},
      {name: 'Pyotr', email: 'pyotr@example.com'},
      {name: 'Sidor', email: 'sidor@example.com'},
    ],
    entries: [
      {title: 'First article', updated: Time.utc(2012, 01, 01, 01, 01)},
      {title: 'Second article', updated: Time.utc(2012, 02, 02, 02, 02)},
      {title: 'Third article', updated: Time.utc(2012, 03, 03, 03, 03)},
    ]
  }
)

feed.author # Xommelier::Atom::Person
feed.contributors[1] # Xommelier::Atom::Person
feed.entries[2] # Xommelier::Atom::Entry

puts feed.to_xml

will output

<?xml version="1.0" encoding="utf-8"?>
<feed xmlns="http://www.w3.org/2005/Atom">
  <title>Xommelier nest elements</title>
  <subtitle>Xommelier is able to build complex objects from very nested hash</subtitle>
  <author>
    <name>Alexander</name>
    <email>al@semyonov.us</email>
  </author>
  <updated>2012-04-04T04:04:00Z</updated>
  <contributor>
    <name>Ivan</name>
    <email>ivan@example.com</email>
  </contributor>
  <contributor>
    <name>Pyotr</name>
    <email>pyotr@example.com</email>
  </contributor>
  <contributor>
    <name>Sidor</name>
    <email>sidor@example.com</email>
  </contributor>
  <entry>
    <title>First article</title>
    <updated>2012-01-01T01:01:00Z</updated>
  </entry>
  <entry>
    <title>Second article</title>
    <updated>2012-02-02T02:02:00Z</updated>
  </entry>
  <entry>
    <title>Third article</title>
    <updated>2012-03-03T03:03:00Z</updated>
  </entry>
</feed>

Built in XML namespaces:

TODO

Validating built XML against RelaxNG
Converting XML Schema, RelaxNG, RelaxNG Compact and DTD into Xommelier Ruby DSL
ActiveRecord-like automatic loading of XML Schema, RelaxNG, RelaxNG Compact and DTD without needing to write it down into ruby code

Contributors

Artyom Semyonov