Yuba
warning
The version of this gem is now 0.0.x. It works, but there must be occasional breaking changes to the API.
Summary
Yuba adds new layers to rails.
- Service
- Form
- ViewModel
It is convenient to use them in combination, but you can use them even individually. If you have difficulties with a large rails application, Yuba helps you.
Installation
Add this line to your application's Gemfile:
gem 'yuba'
And then execute:
$ bundle install
Support
- Rails 5.2+
- Ruby 2.5+
ViewModel
ViewModel is useful when there are many instance variables in controllers.
class PostViewModel < Yuba::ViewModel
property :post
property :author, public: true
property :other, optional: true
def title
post.title
end
def body
post.body
end
end
Post = Struct.new(:title, :body)
post = Post.new('hello', 'world')
view_model = PostViewModel.new(post: post, author: 'willnet')
view.title #=> 'hello'
view.body #=> 'world'
view.author #=> 'willnet'
view.post #=> NoMethodError
property
.property
method registers property to the class.
We need to pass those properties as arguments to the initialize
except when optional: true
is attached. You get ArgumentError if you don't pass property
to initialize
.
Property is default to private. It means you can use it in the internal instance. If you want to use it as public, use public: true
option.
Auto Assign
You can use ViewModel in a controller like the following.
class PostsController < ApplicationController
def show
@view_model = PostViewModel.new(post: post, author: 'willnet')
end
end
In view template, if you want to access post and author, you have to use @view_model
instance variable like @view_model.post.title
. if it feels troublesome, you can write like following
class PostsController < ApplicationController
def show
view_model = PostViewModel.new(post: post, author: 'willnet')
render view_model: view_model
end
end
view_model option of render takes ViewModel, which gets its public methods (include public property) and assigns them to instance variables in the view template. So you can write <%= @post.title %>
instead of <%= @view_model.post.title %>
Service
Service is valuable when a controller has many application logic.
class PostController < ApplicationController
def new
@post = CreatePostService.call(user: current_user).post
end
def create
service = CreatePostService.call(user: current_user, params: params)
if service.success?
redirect_to root_path
else
@post = service.post
render :new
end
end
end
class CreatePostService < Yuba::Service
property :user, public: true
property :params, optional: true
def call
if post.save
notify_to_admin
else
fail!
end
end
def post
user.posts.build(post_params)
end
private
def notify_to_admin
AdminMailer.notify_create_post(post).deliver_later
end
def post_params
params.require(:post).permit(:title, :body)
end
end
.property
method registers property to the class like ViewModel..call
invokes#call
after assigning arguments as properties.#success?
returnstrue
if you don't invoke#fail!
You have inspection methods for properties.
service = CreatePostService.new(user: someuser)
service.has_property?(:user) #=> true
service.has_value?(:user) #=> true
service.has_public_property?(:user) #=> true
service.has_private_property?(:user) #=> false
service.has_required_property?(:user) #=> true
service.has_optional_property?(:user) #=> false
Form
Form is just wrapper of reform-rails for now.
You can see documentation here.
Combination Sample
class ArtistsController < ApplicationController
def new
@view_model = Artist::CreateService.new(params: params).view_model
end
def create
service = Artist::CreateService.call(params: params)
if service.success?
redirect_to artists_path
else
@view_model = service.view_model
render :new
end
end
end
class Artist::CreateService < Yuba::Service
property :params
def call
if form.validate(params)
form.save
else
fail!
end
end
def view_model
Artist::CreateViewModel.new(form: form)
end
private
def form
@form ||= ArtistForm.new(Artist.new)
end
end
class ArtistForm < Yuba::Form
property :name
validates :name, presence: true, length: { maximum: 100 }
end
class Artist::CreateViewModel < Yuba::ViewModel
property :form, public: true
end
generators
You can use generators.
rails generate yuba:service create_artist
rails generate yuba:form artist
rails generate yuba:view_model artist_index
Contributing
You can try to test by doing as following.
git clone https://github.com/willnet/yuba.git
cd yuba
bundle
bundle exec rake
License
The gem is available as open source under the terms of the MIT License.