publishus

Introduction

At this stage this is purely an experimental piece of work to help me understand more of everything. It came about because of our need for a generic publishing framework to support the following needs:

Allow for editing of generic content whilst retaining all the revision history
Allow for publishing individual content items when theyre ready to go live
Allow publishing of all unpublished content at once

Implementation

We looked at some of the versioning frameworks, all of them seemed capable but we saw none that really addressed publishing as such. The one that stood out was vestal_versions[http://github.com/laserlemon/vestal_versions] so we used that as our starting point. This is an extremely thin layer on top of the excellent vestal_versions[http://github.com/laserlemon/vestal_versions]. Vestal versions handles all of the revisioning off to another table and some really nice features but we needed a way to track publishing itself hence some additional attributes on our models and some extra methods. The basic idea is that all publishable items gain a named_scope called published which will filter down the results to only include items that are currently considered “live”. Each instance gains a live method that will return the current live version of that object. For now when using the named_scope you’ve got to call a proxy extension called live. The named_scope returns items that have a published version and the live method actually reverts the items to those versions.

Installation

Prerequisites:

publishus requires vestal_versions by laserlemon Follow instructions on installing vestal_versions[http://github.com/laserlemon/vestal_versions] first

Install the gem:

gem install publishus

In environment.rb:

Rails::Initializer.run do |config|
  ...
  config.gem 'publishus'
  ...
end

At your application root, run:

$ sudo rake gems:install

Example

To version and activate publishing add this to your models:

class Post < ActiveRecord::Base
  publishable
  has_many :comments
end

class Comment < ActiveRecord::Base
  publishable
  belongs_to :page
end

And add some fields to your tables in a migration (hopefully we’ll automate this stuff later):

add_column :posts, :published_at, :datetime
add_column :posts, :deleted_at, :datetime
add_column :comments, :published_at, :datetime
add_column :comments, :deleted_at, :datetime

Using it:

>> page = Page.create(:name => "Page 1")
=> #<Page id: 1, name: "Page 1">
>> page.version 
=> 1 (this bit is vestal versions magic)
>> page.publish!
=> true
>> page.update_attribute(:name, "Page 2")
=> true
>> page
=> #<Page id: 1, name: "Page 2">
>> page.live
=> #<Page id: 1, name: "Page 1">
>> Page.published.live
=> [#<Page id: 1, name: "Page 1">]

And for associations

>> page.comments.create(:body => "Great page")
=> #<Comment id: 1, body: "Great page">
>> page.comments.published
=> []
>> page.comments.first.publish!
=> true
>> page.comments.published.live
=> [#<Comment id: 1, body: "Great page">]
>> page.comments.first.update_attribute(:body, "Just an ok page")
=> true
>> page.comments.create(:body => "Another comment")
=> #<Comment id: 2, body: "Another comment">
>> page.comments
=> [#<Comment id: 1, body: "Just an ok page">, #<Comment id: 2, body: "Another comment">]
>> page.comments.published.live
=> [#<Comment id: 1, body: "Great page">]

Notes