Awesome
ActiveDecorator
A simple and Rubyish view helper for Rails 4, Rails 5, Rails 6, Rails 7, and Rails 8. Keep your helpers and views Object-Oriented!
Features
- automatically mixes decorator module into corresponding model only when:
- passing a model or collection of models or an instance of ActiveRecord::Relation from controllers to views
- rendering partials with models (using
:collection
or:object
or:locals
explicitly or implicitly) - fetching already decorated Active Record model object's association
- the decorator module runs in the model's context. So, you can directly call any attributes or methods in the decorator module
- since decorators are considered as sort of helpers, you can also call any ActionView's helper methods such as
content_tag
orlink_to
Supported versions
-
Ruby 2.1.x, 2.2.x, 2.3.x, 2.4.x, 2.5.x, 2.6.x, 2.7.x, 3.0.x, 3.1.x, 3.2.x, and 3.3 (trunk)
-
Rails 4.2.x, 5.0, 5.1, 5.2, 6.0, 6.1, 7.0, and 7.1 (edge)
Supported ORMs
ActiveRecord, ActiveResource, and any kind of ORMs that uses Ruby Objects as model objects
Usage
- bundle 'active_decorator' gem
- create a decorator module for each AR model. For example, a decorator for a model
User
should be namedUserDecorator
. You can use the generator for doing this (% rails g decorator user
) - Then it's all done. Without altering any single line of the existing code, the decorator modules will be automatically mixed into your models only in the view context.
Examples
Auto-decorating via render
- Model
class Author < ActiveRecord::Base
# first_name:string last_name:string
end
- Controller
class AuthorsController < ApplicationController
def show(id) # powered by action_args
@author = Author.find id
end
end
- Decorator
module AuthorDecorator
def full_name
"#{first_name} #{last_name}"
end
end
- View
<%# @author here is auto-decorated in between the controller and the view %>
<p><%= @author.full_name %></p>
Auto-decorating via AR model's associated objects
- Models
class Author < ActiveRecord::Base
# name:string
has_many :books
end
class Book < ActiveRecord::Base
# title:string url:string
belongs_to :author
end
- Controller
class AuthorsController < ApplicationController
def show(id)
@author = Author.find id
end
end
- Decorator
module BookDecorator
def link
link_to title, url
end
end
- View
<p><%= @author.name %></p>
<ul>
<% @author.books.order(:id).each do |book| %>
<%# `book` here is auto-decorated because @author is a decorated instance %>
<li><%= book.link %></li>
<% end %>
</ul>
Using ActiveDecorator outside of Action View
Sometimes you may want to use decorators outside of Action View, for example,
for background tasks for ActiveJob.
For such use case, ActiveDecorator module provides run_with
method
that takes some kind of Action View and a block.
ActiveDecorator::ViewContext.run_with ApplicationController.new.view_context do
## perform some heavy jobs here
end
Testing
You can test a decorator using your favorite test framework by decorating the model instance with
ActiveDecorator::Decorator.instance.decorate(model_instance)
Considering an Organization
model and its simple decorator:
module OrganizationDecorator
def full_name
"#{first_name} #{last_name}"
end
end
An RSpec test would look like:
describe '#full_name' do
it 'returns the full organization name' do
organization = Organization.new(first_name: 'John', last_name: 'Doe')
decorated_organization = ActiveDecorator::Decorator.instance.decorate(organization)
expect(decorated_organization.full_name).to eq('John Doe')
end
end
Configuring the decorator suffix
By default, ActiveDecorator searches a decorator module named target_class.name + "Decorator"
If you would like a different rule, you can configure in your initializer.
ActiveDecorator.configure do |config|
config.decorator_suffix = 'Presenter'
end
Contributing to ActiveDecorator
- Fork, fix, then send me a pull request.
Copyright
Copyright (c) 2011 Akira Matsuda. See MIT-LICENSE for further details.