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带有载波和多态关联的Rails上传表单

polymorphic-associations carrierwave polymorphism ruby-on-rails-3 ruby-on-rails

Tyler · 技术社区 · 11 年前

我正试图在一个简单的rails应用程序中使用多态关联来减少文件管理的重复性。我正在使用carrierwave来处理文件上传。以下是到目前为止我所拥有的:

应用程序/上传程序/文件上传程序.rb

class FileUploader < CarrierWave::Uploader::Base
  def store_dir
    "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
  end
end

应用程序/模型/附件.rb

class Attachment < ActiveRecord::Base
  mount_uploader :file, FileUploader
  belongs_to :attachable, polymorphic: true
end

应用程序/模型/照片.rb

class Photo < ActiveRecord::Base
  attr_accessible :caption, :attachment
  has_one :attachment, as: :attachable
end

我可以在rails控制台中处理此罚款:

$ rails console
> photo = Photo.new
> attachment = Attachment.new
> attachment.file = File.open('tmp/demo.png')
> photo.attachment = attachment
> photo.save
> photo.attachment
=> #<Attachment id: 3, file: "demo.png", attachable_id: 5, attachable_type: "Photo", created_at: "2013-04-13 16:56:31", updated_at: "2013-04-13 16:56:31">

所以我的问题实际上在于照片控制器:

ActiveRecord::AssociationTypeMismatch in PhotosController#create
Attachment(#70310274945400) expected, got ActionDispatch::Http::UploadedFile(#70310271741380)`

我们非常感谢在这方面的任何帮助。我可能对多态性关联没有最深入的了解。

更新

根据@manoj的建议,我编辑了照片表单以嵌套附件:

<%= f.fields_for :attachment do |attachment_f| %>
    <%= attachment_f.file_field :file %>
<% end %>

我现在在尝试提交表单时遇到此错误:

ActiveRecord::AssociationTypeMismatch (Attachment(#70135925415240) expected, got ActiveSupport::HashWithIndifferentAccess(#70135923190420)):
app/controllers/photos_controller.rb:43:in 'new'
app/controllers/photos_controller.rb:43:in 'create'

2 回复 | 直到 11 年前

Adobe 8 年前

后参数应该是这样的

params => { "photo" => 
               { :attachment_attribute => 
                  {:file => ActionDispatch::Http::UploadedFile}
               }
          }

但你的帖子参数很可能是

params => { "photo" => { :attachment => ActionDispatch::Http::UploadedFile}}

您的视图应该包含fields_for来处理模型中的嵌套。您必须为附件模型的属性“file”创建一个文件字段

<%=form_for @photo do |photo_f|%>
  ....
  <%=photo_f.fields_for :attachment do |attachment_f|%>
     <%= attachment_f.file_field :file%>
  <%end%>
  ....
<%end%>

更新

<%=photo_f.fields_for :attachment_attributes do |attachment_f|%>

在照片模型中添加这些,

accepts_nested_attributes_for :attachment
attr_accessible ..., :attachment_attributes

Saraswathy Renuga 9 年前

<%=form_for @photo do |photo_f|%>
 ....
 <%=photo_f.fields_for :attachment_attributes do |attachment_f|%>
  <%= attachment_f.file_field :file %>
 <%end%>
 ....
<%end%>