versions

A list of libraries to work with ActiveRecord model versioning. See property for an example.

Install

$ sudo gem install versions

Code is on github

Auto

Automatically create a new record on save if should_clone? returns true.

Attachment

Lightweight file attachment handling with transactional safety (only touch the filesystem if everything went fine). This class also handles shared attachments between versions. If you change a version’s content but not the file attached to it, there will not be a new file in the filesystem. Usage example:

class Document < ActiveRecord::Base
  include Versions::Multi
  has_multiple :versions

  include Versions::Attachment
  store_attachments_in :version, :attachment_class => 'Attachment'
end

The Document model now has “file” and “file=” methods.

Multi

Hide many versions behind a single current one. For example if you want
to version the content of a Page class, you should add a ‘version_id’ in
the “pages” table to store the current version and you will need a Version
model with a “page_id” to link back:

class Version < ActiveRecord::Base
  include Versions::Auto
end

class Page < ActiveRecord::Base
  include Versions::Multi
  has_multiple :versions
end

Property integration

You can easily use the Versions gem to version your properties. See better dynamic attributes for an example.

Testing Gotcha

If you are testing your application with AfterCommit, you should note that the ‘after_commit’ code will NEVER BE EXECUTED if you have enabled transactional fixtures. You can fix this by disabling transactional fixtures in the tests where you need the after_commit code to execute (save file for example).

class DocumentTest < Test::Unit::TestCase
  self.use_transactional_fixtures = false
  
  # ...
end