A lightweight Ruby gem that provides elegant attribute handling, parameter casting, and validation.
- Attribeauty::Params: Type-cast, transform, and validate incoming parameters for any ruby app.
Add to your Gemfile:
gem 'attribeauty'Then run:
$ bundle installOr install directly:
$ gem install attribeautyAttribeauty::Params solves a common problem in web applications: parameters arrive as strings, but your application needs them as proper data types. It elegantly handles:
- Type casting (string → integer, boolean, etc.)
- Required field validation
- Conditional exclusion of nil/empty values
- Nested data structures (hashes and arrays)
- Default values
- Plain ruby compatible
Note the following examples use rails, but also apply to your Roda/Sinatra/Hanami/Rack app
In a Rails controller:
class ApplicationController < ActionController::Base
private
def params_filter
Attribeauty::Params.with(params.to_unsafe_h)
end
endThen in your specific controllers:
class UsersController < ApplicationController
def create
if params_filter.errors.any?
flash[:alert] = params_filter.errors.join(", ")
render :new
else
@user = User.create(user_params)
redirect_to @user, notice: "User created successfully"
end
end
private
def user_params
params_filter.accept do
root :user do
attribute :username, :string, required: true
attribute :age, :integer
attribute :active, :boolean, default: true
attribute :email do
attribute :address, :string, required: true
attribute :verified, :boolean, default: false
end
end
end
end
endInput params:
{
'user' => {
'username' => 'js_bach',
'age' => '42',
'job_title' => '',
'email' => {
'address' => 'js@bach.music'
}
}
}Output after processing:
{
username: 'js_bach',
age: 42,
active: true,
email: {
address: 'js@bach.music',
verified: false
}
}attribute :job_title, :string, exclude_if: [:nil?, :empty?]params_filter.accept(required: true) do
# All attributes will require values unless overridden
attribute :username, :string
attribute :email, :string, allows: :nil? # Exception to the global rule
endparams_filter.accept! do
# Will raise Attribeauty::MissingAttributeError if required fields are missing
endattribute :addresses do
attribute :street, :string
attribute :city, :string
endWorks with both single objects and arrays of objects.
Define your own attribute types:
Attribeauty.configure do |config|
config.types[:email] = MyTypes::Email
end
module MyTypes
class Email
def cast(value)
value.to_s.downcase.strip
end
end
end# config/initializers/attribeauty.rb
Rails.application.reloader.to_prepare do
Attribeauty.configure do |config|
config.types[:string] = ActiveModel::Type::String
config.types[:boolean] = ActiveModel::Type::Boolean
config.types[:date] = ActiveModel::Type::Date
config.types[:time] = ActiveModel::Type::Time
config.types[:datetime] = ActiveModel::Type::DateTime
config.types[:float] = ActiveModel::Type::Float
config.types[:integer] = ActiveModel::Type::Integer
end
endAfter checking out the repo:
- Run
bin/setupto install dependencies - Run
rake testto run the tests - Run
bin/consolefor an interactive prompt
Bug reports and pull requests are welcome on GitHub at https://github.com/tobyond/attribeauty.
The gem is available as open source under the terms of the MIT License.