Screencast: Model Versioning

• Vestal Versions
• Hirb
• Full episode source code

Verwendung in der Konsole

[bash]
sudo rake gems:install
script/generate vestal_versions_migration
script/generate migration version_existing_pages
rake db:migrate
[/bash]

Quellcode:

[ruby]
# config/environment.rb
config.gem ‚laserlemon-vestal_versions‘, :lib => ‚vestal_versions‘, :source => ‚http://gems.github.com‘

# models/page.rb
class Page < ActiveRecord::Base
versioned
end

# version_existing_pages migration
say_with_time "Setting initial version for pages" do
Page.find_each(&:touch)
end

# pages_controller.rb
def show
@page = Page.find(params[:id])
@page.revert_to(params[:version].to_i) if params[:version]
end

# script/console
p = Page.all
p.versions
p.revert_to(7.minutes.ago)
p.content
p.revert_to(:last)

[/ruby]

[xhtml]
<p>
<%= link_to "Edit", edit_page_path(@page) %>
| Version <%= @page.version %>
<% if @page.version > 1 %>
| <%= link_to "Previous version", :version => @page.version-1 %>
<% end %>
<% if params[:version] %>
| <%= link_to "Latest version", :version => nil %>
<% end %>
</p>
[/xhtml]