Sample DSL

password_resetable.rb

# frozen_string_literal: true

module PasswordResetable
  extend ActiveSupport::Concern

  included do
    attr_reader :reset_password_token
  end

  # Check if the given token is valid to reset the password
  def password_resetable_with?(token)
    PasswordResetable::Token.create(token).alive? &&
      !!BCrypt::Password.valid_hash?(reset_password_digest) &&
      BCrypt::Password.new(reset_password_digest) == token
  end

  # Set the model so its password can be reset 
  def password_resetable!
    duration = Rails.application.credentials.dig(:password, :reset_token, :duration_in_mins)
    update!(reset_password_token: PasswordResetable::Token.new(duration))
  end

  # The datetime when the password cannot be longer reset 
  def reset_password_expires_at
    reset_password_token&.expires_at
  end

  # Renew the token to be able to reset the password   
  def reset_password_token=(token)
    @reset_password_token      = token
    self.reset_password_digest = (BCrypt::Password.create(token) if token)
    token
  end

  # Returns the digest of the password
  def reset_password_digest
    column_reset_password_digest_defined? ? super : no_column_reset_password_digest!
  end

  private

  def column_reset_password_digest_defined?
    self.class.column_names.include?("reset_password_digest")
  end

  def no_column_reset_password_digest!
    raise("You need to add String column :reset_password_digest to your model!")
  end

  def reset_password_digest=(digest)
    @reset_password_token        = nil if digest.nil?
    self[:reset_password_digest] = digest
  end
end