带有 jQ​​uery-File-Upload 和嵌套 Paperclip 的 Rails 3.1

Question

我正在使用带有 Paperclip 的 Rails 3.1，并正在寻找一种实现 jQuery-File-Upload 的方法。

按照示例，我有一个基本的工作设置：
blueimp jquery=file-upload

但是当我介绍了一个嵌套属性模型，其中上传嵌套在帖子中时，它就崩溃了。给出的错误是“未知属性：图片”。了解 uploads_attributes 可能必须单独编组，特别是对于图片参数，从查询脚本到控制器。如何指定参数？

请求：http://localhost:3002/posts/3

错误：

ActiveRecord::UnknownAttributeError in PostsController#update

unknown attribute: picture

Rails.root: /Users/mjwong/workspace/testupload
Application Trace | Framework Trace | Full Trace

app/controllers/posts_controller.rb:63:in `block in update'
app/controllers/posts_controller.rb:62:in `update'

请求

参数：

{"utf8"=>"✓",
 "_method"=>"put",
 "authenticity_token"=>"1SYnIX+Y5PxM7PskzV/zocCJfh60tyGkUBdwu7OmNo8=",
 "post"=>{"title"=>"test",
 "content"=>"test",
 "picture"=>#<ActionDispatch::Http::UploadedFile:0x007fe346dbeaf8 @original_filename="Alva 2.jpg",
 @content_type="image/jpeg",
 @headers="Content-Disposition: form-data; name=\"post[picture]\"; filename=\"Alva 2.jpg\"\r\nContent-Type: image/jpeg\r\n",
 @tempfile=#<File:/var/folders/_w/24l2jy1563d2qqh8w0x4qmgh0000gn/T/RackMultipart20111030-3671-10zn91c>>},
 "commit"=>"Update Post",
 "id"=>"3"}

型号：

class Post < ActiveRecord::Base
   has_many :uploads, :dependent => :destroy
   accepts_nested_attributes_for :uploads, :allow_destroy => true
end

class Upload < ActiveRecord::Base
   belongs_to :post
   has_attached_file :picture, :styles => {:thumb   => "100x100#",
                                           :small   => "300x300>",
                                           :large   => "600x600>" },
   :url => "/system/:class/:attachment/:id/:style/:basename.:extension",
   :path => ":rails_root/public/system/:class/:attachment/:id/:style/:basename.:extension"

   validates_attachment_size :picture, :less_than => 500.kilobytes
   validates_attachment_content_type :picture, :content_type => ['image/jpeg', 'image/png']
end

控制器：

class HomeController < ApplicationController
   def index
      @upload  = Upload.new
   end
end

Answer 1

别忘了运行rails g paperclip posts picture 之类的迁移并运行rake db:migrate