DateAsBool

DateAsBool is a simple Rails Gem to get both a datetime and a boolean behaviour from the same database column.

Installation

Add this line to your application's Gemfile:

gem 'date_as_bool'

And then execute:

$ bundle

Or install it yourself as:

$ gem install date_as_bool

Usage

Let's say you have a users table with column verified_at:datetime.

Add

class User < ApplicationRecord
  date_as_bool :verified_at
  ...

Now you can use user.verified or user.verified? to test for verified_at presence, and user.verified! as an alias for user.update(verified_at: Time.now).

You can change the field with user.update(verified: bool). If false, it resets verified_at to nil, if true, it sets it to Time.now.

You also get the scopes User.verified, equivalent to User.where.not(verified_at: nil), and User.not_verified equivalent to User.where(verified_at: nil).

Methods

User.verified == User.where.not(verified_at: nil)
User.not_verified == User.where(verified_at: nil)
user.verified == user.verified_at.present?
user.verified? == user.verified_at.present?
user.verified! == user.update(verified: true) == user.update(verified_at: Time.now)
user.update(verified: false) == user.update(verified_at: nil)

Motivation

Often, when you need a boolean flag on a model, you can accomplish more by using a datetime attribute instead, that captures the first time the flag turned on. But to recover the simplicity of dealing with a boolean instead of a datetime you have to write some lines of code.

So, I found myself quite often with the following design pattern:

# == Schema Information
#
# Table name: users
#
#  id          :integer          not null, primary key
#  verified_at :datetime
#  ...
#

class User < ApplicationRecord
  scope :verified,     -> { where.not(verified_at: nil) }
  scope :not_verified, -> { where(verified_at: nil) }

  def verified=(bool)
    self.verified_at = bool ? Time.now : nil
  end

  def verified
    verified_at.present?
  end
  alias verified? verified

  def verified!
    verified = true
    save
  end

  # ...
end

This way, I can both use User.verified and User.where(verified_at: 2.days.ago..Time.now).

DateAsBool abstracts this behaviour in one line.

Advanced Usage

If you want to give a different name to the boolean method, you can specify it as the second argument.

date_as_bool :verified_at is just a shortcut for date_as_bool :verified_at, :verified.

Contributing

Bug reports and pull requests are greatly appreciated.

License

The gem is available as open source under the terms of the MIT License.

carlomartinucci/date_as_bool