Question

Hi i have a code i would like to refactor

def gear_type
  @gear_type ||= self.class.gear_types.find{|gears| gears["id"]==source["gear_type_id"]}["text"] if source["gear_type_id"]
end

def brand
  @brand ||= self.class.brands.find{|node| node["id"]==source["brand_id"].to_s}["text"] if source['brand_id']
end

what is best way? to use eval or define method? i’ve tried this but there are some error i can’t discover yet:

%w(gear_type brand).each do |meth|
  define_method(meth){
    instance_variable_get("@#{meth}") rescue
      instance_variable_set("@#{meth}", self.class.send(meth.pluralize).find{|node| node["id"]==source["#{meth}_id"]}["text"]) if source["#{meth}_id"]
  }
end

Answer 1

I’d just write a common finder method that you can parameterize:

def gear_type
  @gear_type ||= generic_finder :gear_types, "gear_type_id"
end

def brand
  @brand ||= generic_finder :brands, "brand_id"
end

def generic_finder(collection, primary_key)
  self.class.send(collection).each do |object|
    return object["text"] if object["id"] == source[primary_key]
  end if source[primary_key]
  nil
end