Carrierwave mongoid 上传。得到一个未定义的方法“空？”对于#<ActionDispatch::Http::UploadedFile:0x00000109968c50>

Question

我正在尝试将图像文件上传到我的 Rails 服务器，但我一直碰壁。

这是我的表单themed_controller/new，

= form_for(@campaign, validate: true, :html => {:multipart => true}) do
        .form-group
            %label.col-sm-3.control-label
                Campaign Name
            .col-sm-6
                %input#title.form-input{ name: "@campaign[campaign_title]", placeholder: "Campaign Title",  required: "", type: "text", value: ""}/
        .form-group
            %label.col-sm-3.control-label
                Campaign Description
            .col-sm-6
                %textarea.form-input{ name: "@campaign[campaign_description]", placeholder: "Campaign Description",  required: "", value: ""}

        .form-group
            %label.col-sm-3.control-label
                Pick stories
            .col-sm-6
                %select#themed_campaign_live_story_ids{name: "@campaign[live_story_ids][]", :multiple => true,  :required=> true, value: []}
                -# = f.select 'live_story_ids[]', [], :multiple => true
        #date-range
            .form-group#valid-from
                %label.col-sm-3.control-label
                    Campaign runs from
                .col-sm-6
                    %input.form-input#themed_campaign_valid_from{ name: "@campaign[valid_from]",:class => 'jquery-ui-date valid-from',  :data => {:provide =>"datepicker", :behaviour => "datepicker"},  required: "", type: "text", value: ""}/

            .form-group#valid-till
                %label.col-sm-3.control-label
                    Campaign runs till
                .col-sm-6
                    %input.form-input#themed_campaign_valid_till{ name: "@campaign[valid_till]",:class => 'jquery-ui-date valid-till',  :data => {:provide =>"datepicker", :behaviour => "datepicker"},  required: "", type: "text", value: ""}/
        .form-group#valid-till
            %label.col-sm-3.control-label
                Upload cover (1280x350)
            .col-sm-6
                -#upload-image.btn.btn-medium.btn-green{ :data => {:url => "/campaign/upload"} }

                #upload-image
                    %input#image_media{name: "@campaign[cover]", type: "file"}/
        .form-group
            .col-sm-offset-3.col-sm-6
                %button.form-button.btn-large.btn-green.btn#campaign-submit{type: "submit"}
                    Set up Campaign

这是我的创建方法

def create
    campaign = params[:@campaign]
    campaign['added_by_email'] = current_user.email
    @campaign = ThemedCampaign.create(campaign)

    if @campaign.save
        img_attr =  params[:@campaign]['cover']
        image = Campaign.new img_attr
        @campaign.cover = image
        Resque.enqueue(ImageQueue,image.id)
        #render :json => image.to_jq_upload.to_json
    end

    redirect_to '/admin/themecampaign'
end

我为此创建了一个单独的上传器，

# encoding: utf-8

class CampaignUploader < CarrierWave::Uploader::Base

    # Include RMagick or MiniMagick support:
    include CarrierWave::MiniMagick

    # Choose what kind of storage to use for this uploader:
    storage :file
    # storage :fog

    before :cache, :save_original_filename

    # Add a white list of extensions which are allowed to be uploaded.
    # For images you might use something like this:
    def extension_white_list
        %w(jpg jpeg png)
    end

    # Override the directory where uploaded files will be stored.
    # This is a sensible default for uploaders that are meant to be mounted:
    def store_dir
        "uploads/campaigns/#{model.id}/"
    end

end

这是我的活动模式，其中包含图像

class Campaign
    include Mongoid::Document
    include Mongoid::Timestamps
    include Mongoid::Paranoia
    include Rails.application.routes.url_helpers

    mount_uploader :cover, CampaignUploader
end

现在，当我上传表单时，我不断收到undefined methodempty？为了 ＃

> NoMethodError - undefined method `empty?' for
> #<ActionDispatch::Http::UploadedFile:0x00000109968c50>:    () Users/skmvasu/.rvm/gems/ruby-2.0.0-p451/bundler/gems/mongoid-bc72426681d5/lib/mongoid/attributes/processing.rb:21:in
> `process_attributes'    ()
> Users/skmvasu/.rvm/gems/ruby-2.0.0-p451/bundler/gems/mongoid-bc72426681d5/lib/mongoid/document.rb:111:in `block in initialize'    ()
> Users/skmvasu/.rvm/gems/ruby-2.0.0-p451/bundler/gems/mongoid-bc72426681d5/lib/mongoid/threaded/lifecycle.rb:84:in
> `_building'    ()
> Users/skmvasu/.rvm/gems/ruby-2.0.0-p451/bundler/gems/mongoid-bc72426681d5/lib/mongoid/document.rb:105:in `initialize'   actionpack (4.0.2)
> lib/action_dispatch/routing/url_for.rb:104:in `initialize'  
> app/controllers/themed_campaign_controller.rb:57:in `new'  
> app/controllers/themed_campaign_controller.rb:57:in `create'

本质上，这在尝试使用图像属性调用 Campaign.new 时会爆炸。我以为 image 字段是 nil 但是当我从服务器检查 img_attr 时，我注意到上传的文件存在并且 temp 字段正确地指向本地副本。

当我深入挖掘时，我注意到我的主题控制器中的cover 是无效的。

MOPED: 127.0.0.1:27017 INSERT       database=mangoweb_development collection=themed_campaigns

documents=[{"_id"=>BSON::ObjectId('53ba605c5661731da8060000'), "campaign_title"=>"测试活动", "campaign_description"=>"测试 广告系列描述", "live_story_ids"=>["53a9b3e5566173146e030000", “5343eafc5661731195030000”，“5343eacc566173117f030000”， "5343eadf5661731189030000"], "valid_from"=>2014-07-07 00:00:00 UTC, "valid_till"=>2014-07-22 00:00:00 UTC, "封面"=>"#", "add_by_email"=>"xxxxxxxxx", "campaign_sane_title"=>"Test-campaign", "updated_at"=>2014-07-07 08:54:52 UTC，“created_at”=>2014-07-07 08:54:52 UTC}] 标志=[] 命令数据库=mangoweb_development 命令={:getlasterror=>1, :w=>1} 运行时间：11.9600ms #

我在这里做错了什么？为什么封面的值是上传的对象引用的字符串版本，而不是文件值，为什么没有创建图像？

过去 2 天我一直在处理这个问题，并查看了各种参考资料。我知道，我一定在做一些非常愚蠢的事情，但我无法得到它。

请帮我解决这个问题。提前致谢。

Answer 1

您可以使用表单实例对象轻松处理此问题

改变

 form_for(@campaign, validate: true, :html => {:multipart => true}) do

到

 form_for(@campaign, validate: true, :html => {:multipart => true}) do |f|

并在引用表单字段时使用f

%textarea.form-input{ name: "@campaign[campaign_description]", placeholder: "Campaign Description",  required: "", value: ""}

应该改为

f.text_area :campaign_description, placeholder: "Campaign Description",  required: "", value: ""

对于文件字段

f.file_field :cover

让我知道这是否有效