ActsAsVersioned for MongoMapper

Basic MongoMapper port of technoweenie's acts_as_versioned. Stores changed attributes in a single collection using a general Hash key.

class Page
  include MongoMapper::Document

  plugin MongoMapper::Acts::Versioned

  key :title, String
end

page = Page.create(:title => 'title')
page.version              # => 1
page.versions.size        # => 1

page.title = 'new title'
page.save

page = page.reload
page.version              # => 2
page.versions.size        # => 2
page.title                # => 'new title'

page.revert_to!(1)

page = page.reload
page.version              # => 1
page.versions.size        # => 2
page.title                # => 'title'

Default ignored keys are:

• "_id"
• "created_at"
• "updated_at"
• "creator_id"
• "updater_id"
• "version"
• "_type"
• "_versioned_type"
• versioned_foreign_key

Simply add do_not_version 'new_skipped_key', 'another_skipped_key' somewhere in your model.

• For MongoMapper <= 0.8.6, see the master branch of this repository.

• See the next branch of this repository.

Since 0.3.0, versions have moved into standalone documents rather than embedded documents, mostly for performance reasons.
In hindsight, it didn't really make much sense to load all of a document's versions in every query (unless a query specified .fields without :versions), on top of the actual document itself.
Versions are now only loaded when specifically requested. Existing versions in your system will however not be automatically updated.

Here's an example script that can do it for you.
Assuming models called Page and Template, you can convert its old versions through a script like such:

models = [Page, Template]

models.each do |model|
  model.const_set(:Version, Class.new {
    include MongoMapper::EmbeddedDocument
    key :modified
    key :version
  })

  model.many :versions, class_name: "#{model.name}::Version"

  model.all.each do |document|
    document.versions.each do |old_version|
      MongoMapper::Acts::Versioned::DocumentVersion.create(
        entity_type: model.name,
        entity_id:   document.id,
        modified:    old_version.modified,
        version:     old_version.version
      ) || warn("Didnt create new version for #{old_version.inspect}")
    end
  end
end

Make sure to specify :require => 'acts_as_versioned' in your Gemfile.

• MongoMapper 0.11.1, 0.13.1, 0.14.0
• Ruby 1.9.2 up to 2.4.0

See LICENSE.