Ruby on rails 如何在rails中干燥给定代码

我的控制器中有这个代码，它有点长。有谁能指导我如何干燥这个：

def edit
    @employee = Employee.where(id: params[:id]).first
    unless @employee.profile
      @employee.build_profile
    end
    unless @employee.current_address
      @employee.build_current_address
    end
    unless @employee.permanent_address
      @employee.build_permanent_address
    end
    unless @employee.emergency_contact
      @employee.build_emergency_contact
    end
    unless @employee.attachments
      @employee.attachments.build
    end
  end

---

在这种情况下，你可以借助模型

在控制器中

def edit
  @employee = Employee.find(params[:id])
  @employee.create_association_instance  
end

在employee.rb模型中创建新方法

def create_association_instance
  self.build_profile unless self.profile    
  self.build_current_address unless self.current_address
  self.build_permanent_address unless self.permanent_address    
  self.build_emergency_contact unless self.emergency_contact    
 self.attachments.build unless self.attachments 
end

---

防御性的编程通常很糟糕。您应该在数据库中有完整的有效条目，创建一个rake任务，并在需要时更新所有条目