Lean::Attributes
Lean::Attributes is inspired by gems like Virtus or FastAttributes. It allows one to define typed attributes on arbitrary Ruby classes. Lean::Attributes aims to be roughly as fast as FastAttributes but has a few syntactical differences in addition to support for default values.
Status
Installation
Add this line to your Gemfile:
gem 'lean-attributes', '~> 0.2'
And then execute:
$ bundle
Or install it yourself with:
$ gem install lean-attributes
Usage
require 'lean-attributes'
class Book
include Lean::Attributes
attribute :title, String
attribute :name, String
attribute :pages, Integer
attribute :authors, Array
attribute :published, Date
attribute :sold, Time, default: :time_now
attribute :finished, DateTime
attribute :format, Symbol, default: :hardcover
private
def time_now
Time.now.utc
end
end
book = Book.new(
title: 'There and Back Again',
name: 'The Hobbit',
pages: '200',
authors: 'Tolkien',
published: '1937-09-21',
)
book.finished = '1937-08-20 12:35'
book.format # => :hardcover
book.sold # => 2015-09-15 23:06:34 UTC
book # =>
# #<Book:0x007fcb7613b610
# @authors=["Tolkien"],
# @finished=
# #<DateTime: 1937-08-20T12:35:00+00:00 ((2428766j,45300s,0n),+0s,2299161j)>,
# @format=:hardcover,
# @name="The Hobbit",
# @pages=200,
# @published=#<Date: 1937-09-21 ((2428798j,0s,0n),+0s,2299161j)>,
# @sold=2015-09-15 23:06:34 UTC,
# @title="There and Back Again">
Coercion
The coercion capabilities included in this gem are poor by design and will only handle trivial use cases. Whenever you set an attribute, generated coercion methods are called. You can override these methods to create your own coercion rules.
class ReadingProgress
include Lean::Attributes
attribute :current_page, Integer, default: 1
private
def coerce_current_page(value)
value = begin
value.to_i
rescue NoMethodError
1
end
value = 1 if value < 1
value
end
end
Another way to contain such behavior is to create a CurrentPage
class to represent your attribute instead of an Integer. The power is yours.
Benchmarks
Lean::Attributes is meant to be relatively lightweight and fast.
FastAttributes: without values : 3499535.3 i/s
Lean::Attributes: without values : 3467944.9 i/s - 1.01x slower
Lean::Attributes: integer values for integer attributes : 151398.8 i/s - 23.11x slower
FastAttributes: integer values for integer attributes : 140099.8 i/s - 24.98x slower
Lean::Attributes: string values for integer attributes : 139070.9 i/s - 25.16x slower
FastAttributes: string values for integer attributes : 124387.2 i/s - 28.13x slower
Virtus: integer values for integer attributes : 36776.0 i/s - 95.16x slower
Attrio: integer values for integer attributes : 19452.5 i/s - 179.90x slower
Virtus: without values : 18184.8 i/s - 192.44x slower
Attrio: string values for integer attributes : 17689.9 i/s - 197.83x slower
Attrio: without values : 12769.1 i/s - 274.06x slower
Virtus: string values for integer attributes : 5043.4 i/s - 693.88x slower
Versioning
Lean:Attributes uses Semantic Versioning 2.0.0
Contributing
- Fork it ( https://github.com/lleolin/lean-attributes/fork )
- Create your feature branch (
git checkout -b my-new-feature
) - Commit your changes (
git commit -am 'Add some feature'
) - Push to the branch (
git push origin my-new-feature
) - Create new Pull Request
Copyright
Copyright © 2015 R. Elliott Mason – Released under MIT License