/has_versions

A simple plugin to version ActiveRecord objects

Primary LanguageRubyMIT LicenseMIT

has_versions

has_versions is a simple plugin to version ActiveRecord objects. The versioned data is saved using Marshal. You can specify what attributes are going to be versioned and if versioning is automatically or not.

Installation

  1. Install the plugin with script/plugin install git://github.com/fnando/has_versions.git

  2. Generate a migration with script/generate migration create_versions and add the following code:

    class CreateVersions < ActiveRecord::Migration def self.up create_table :versions do |t| t.references :versionable, :polymorphic => true t.references :user t.binary :data t.datetime :created_at t.integer :version, :default => 0, :null => false end

     add_index :versions, :versionable_type
     add_index :versions, :versionable_id
     add_index :versions, :user_id
     add_index :versions, :version
    

    end

    def self.down drop_table :versions end end

  3. Add the column version to all models you want to be versioned; first create the migration:

    script/generate migration add_version_support_to_posts

Then add the following code:

class AddVersionSupportToPosts < ActiveRecord::Migration
  def self.up
    change_table :posts do |t|
      t.integer :version, :default => 0, :null => false
    end
  end

  def self.down
    remove_column :posts, :version
  end
end
  1. Run the migrations with rake db:migrate

Usage

  1. Add the association to your User model

    class User < ActiveRecord::Base has_many :versions, :dependent => :nullify end

  2. Add the method call has_comments to your model.

    class Post < ActiveRecord::Base has_versions end

    post = Post.first user = User.first

    create the version only if any versioned attribute

    has changed

    post.create_version

    create a version anyway!

    post.create_version!

    retrieve current version number

    post.version

    retrieve current version object

    post.versions.current

    retrieve version #3

    post.versions.get(3)

    retrive version #3 and

    raise SimplesIdeias::Versions::Exception::VersionNotFound

    if not found

    revert to a specific version,

    returning nil if version is not found

    post.versions.revert_to(1)

    revert to a specific version and

    raise SimplesIdeias::Versions::Exception::VersionNotFound

    if version is not found

    post.versions.revert_to!(100)

    save an object without creating a version

    post.save_without_version # => same as post.save post.save_without_version(false) # => same as post.save(false) post.save_without_version! # => post.save!

    set the user that created the version

    post.version_author = user

    retrieve version author

    post.version_author

    return true if version number >= 1

    post.versioned?

    return true if current saving process

    is not meant to create a version

    post.save_without_version?

    list of versioned attributes

    post.versioned_attributes

    you can control weither to create a version or not by

    overriding the method create_version?

    class Post < ActiveRecord::Base has_versions

    def create_version? false end end

    other possible options

    has_versions :attributes => :all has_versions :attributes => :content has_versions :attributes => %w(content excerpt) has_versions :auto => false has_versions :except => :formatted_content

What about displaying a diff from two different versions? Well, you can use the helper method diff.

<%= diff @newer.data['content'], @newer.data['content'] %>

Use this CSS to display some formatted text:

.diff ins {
	background: #baffa6;
	text-decoration: none;
}

.diff del {
	background: #f88;
	text-decoration: none;
}

NOTE: You should have an User model. Otherwise, this won't work!

To-Do

  • Create view helpers to display formatted version diffs

Maintainer

License

(The MIT License)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.