active_stripper

Small gem that allows pre processing of attributes (downcase, strip...) by creating prepended custom setters.

This allows preprocessing of attributes before a custom accessor declared inside the class body is called

Only works on ruby 2.x since the prepend instruction is used.

Named active_stripper for search purposes (that and because I <3 pun) but doesn't have any dependencies (ActiveSupport or otherwise) and can be used any attr_accessor in any class.

It defines setter methods but you can still use your owns in the class definition, the one generated from the gem will be called last though.

Conduct and Contribution

Please review our CODE OF CONDUCT AND CONTRIBUTION rules (only takes a few seconds to read) before any request.

STATUS

Install

Bundler

In your gemfile add gem 'active_stripper', '~> 0.2.0'

Without Bundler

gem install 'active_stripper'

Helpers listing

You can find basic available helpers here If you want a new one added in the library, please, feel free to open an issue.

Usage

Syntax

After the call to include, you can use the gem in the following ways

# will look up the method #processor_method in ActiveStripper::Helpers
# if inexistent, will look up in the current object for it
# then apply it on all listed fields
strip_value_from : field1, field2, field3, :processor_method

# Will apply all processor method in the declaration order on all listed fields
# The processors are executed in the same order as defined in the array (left to right)
strip_value_from : field1, field2, field3, [:processor_method, :processor_method2]

# Will lookup processor_method in the module ModuleName, for application on all fields
# processor_method2 is looked up in ActiveStripper::Helpers first and
# then in the current object if not found
strip_value_from : field1, field2, field3, { processor_method: { module: :ModuleName }, processor_method2: nil }

# The processor here are executed in the inverse order of declaration (bottom to top)
strip_value_from : field1, :processor_method2
strip_value_from : field1, :processor_method

Active record

class Foo < ActiveRecord::Base
  # contain field named text_field

  include ActiveStripper

  strip_value_from :text_field, [:to_lower_stripper, :white_space_stripper]


  def text_field=(val)
    super(val + " in class definition custom overwrite")
  end
end

foo = Foo.new(text_field: "   HeLLo WhitespacEEEs          \t")
foo.text_field => "hello whitespaceees in class definition custom overwrite"

foo = Foo.new
foo.text_field = "   HeLLo WhitespacEEEs          \t"
foo.text_field => "hello whitespaceees in class definition custom overwrite"

# Advantage here is that the processed value is visible without executing a hook like before_validation etc etc

Vanilla Ruby

class Foo
  include ActiveStripper

  attr_accessor :text_field

  strip_value_from :text_field, :white_space_stripper

  def text_field=(val)
    @text_field = val + " in class definition custom overwrite   "
  end
end

foo = Foo.new
foo.text_field = "   HeLLo WhitespacEEEs          \t"
foo.text_field => "hello whitespaceees in class definition custom overwrite   "

class Bar < Foo
  strip_value_from :text_field, :white_space_stripper

  def text_field=(val)
    super(val + " child class definition custom overwrite   ")
  end
end

bar = Bar.new
bar.text_field = "   HeLLo WhitespacEEEs          \t"
bar.text_field # => "hello whitespaceees child class definition custom overwrite in class definition custom overwrite   "
# Note that the most ancient definition is never processed

Shahor/active_stripper