A module to make a clean and simple filtering

Filterable.rb

module Filterable
  extend ActiveSupport::Concern

  module ClassMethods
    def filter(filtering_params)
      results = self.where(nil)
      filtering_params.each do |key, value|
        results = results.public_send(key, value) if value.present?
      end
      results
    end
  end
end
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class User < ApplicationRecord
  include Filterable

  scope :email_q, -> (email) { where("LOWER(email) like ?", "%#{email.downcase}%")}
  scope :name_q, -> (name) { where("LOWER(name) like ?", "%#{name.downcase}%")}
end
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def index
  @users = User.filter(filtering_params)
end

def filtering_params
  params.slice(:email_q, :name_q)
end