Search and Filter Rails Models Without Bloating Your Controller

# app/models/concerns/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

# app/models/product.rb
class Product
  include Filterable
  ...
end

#app/controllers/product_controller.rb
def index
  @products = Product.filter(params.slice(:status, :location, :starts_with))
end