为什么当我在rails 4数据库中使用carrierwave上传图像时会回滚？

Question

我尝试在rails 4中使用carrierwave保存图像文件,但是当提交按钮时单击数据库是否回滚??? 为什么？

如果我不选择图像上传,只发送字符串,所有工作正常但如果我发送图像文件我得到这样的错误:

TypeError: can't cast ActionDispatch::Http::UploadedFile to string: INSERT INTO "items" ("created_at", "description", "image", "name", "store_id", "sub_items", "title", "updated_at") VALUES (?, ?, ?, ?, ?, ?, ?, ?)
   (0.2ms)  rollback transaction
*** ActiveRecord::StatementInvalid Exception: TypeError: can't cast ActionDispatch::Http::UploadedFile to string: INSERT INTO "items" ("created_at", "description", "image", "name", "store_id", "sub_items", "title", "updated_at") VALUES (?, ?, ?, ?, ?, ?, ?, ?)

我的看法 :

<%= form_for @items, :url => dashboard_create_items_path(@store.id), :html => {:multipart => true} do |f| %>
  <%= f.label :name, 'Name' %>
  <%= f.text_field :name %><br />
  <%= f.label :title, 'Title' %>
  <%= f.text_field :title %><br />
  <%= f.label :image, 'Image' %>
   <%= f.file_field :image %><br />
  <%= f.label :description, 'Description' %>
  <%= f.text_field :description %><br />
  <%= f.label :sub_items %><br>
  <%= f.select :sub_items, options_for_select([["true", true], ["false", false]]), :selected => 'true' %><br />
  <%= f.submit %>
<% end %>

我的控制器:

def create_items    
    store = Store.find(params[:id])
    @items = store.items.create(item_params)

    if @items
      redirect_to dashboard_show_items_url(@items.id, store.id)
    else
      redirect_to dashboard_new_items_url
    end
  end

private

    def item_params
      params.require(:item).permit(:name, :title, :image, :description, :sub_items, :store_id)
    end

我什么时候错了请告诉我？谢谢你

Answer 1

您可能会看到此错误消息,因为Carrierwave尚未在您的模型中初始化.

mount_uploader需要将carrierwave方法添加到模型中的图像字段,如下所示:

class Item < ActiveRecord::Base
  mount_uploader :image, ImageUploader
end

(有关详细信息,请参阅文档)