Rails Railscasts 视频中 #009 File uploading by Carrierwave
我按照视频教程上照做的 在保存的时候出现这个错误：
ActiveModel::MassAssignmentSecurity::Error in PostsController#create
Can't mass-assign protected attributes: attachmentable Rails.root: /home/user/upload
Application Trace | Framework Trace | Full Trace
app/controllers/posts_controller.rb:48:in block in create'
app/controllers/posts_controller.rb:45:increate'
Request
Parameters:
{"utf8"=>"✓", "authenticity_token"=>"n7Si25bOgGofURmyxghGYYJrHdyj4IYEljLkFUfIZpg=", "post"=>{"title"=>"w", "content"=>"w"}, "attachment"=>"03.jpg", "commit"=>"Create Post"} Show session dump
求高手解答下：
