ruby-on-rails - rails4 + mongoid + carrierwave + fog + jquery-file-upload - TypeError(没有将 nil 隐式转换为 String)

Question

我不知道我在上传多个文件时做错了什么。我有另一个具有类似设置的 rails4 应用程序，只是使用 postgresql 而不是 mongoid，我还没有遇到这个问题。我不确定它是否与 carrierwave-mongoid 或什么有关。我如何进一步缩小实际导致 TypeError 的范围？？？

更新 重新创建了整个应用程序并使用了 Postgresql，并遇到了完全相同的问题.. 所以它不像我想的那样与 carrierwave-mongoid 隔离。

开发日志

       Started POST "/images" for 127.0.0.1 at 2014-10-02 11:28:28 -0400
Processing by ImagesController#create as JSON
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"MPtXrjrQ+dLb67LVD+aYUrMIYfCUBQWLOaOztlB2sSU=", "image"=>{"gallery_id"=>"3", "file"=>[#<ActionDispatch::Http::UploadedFile:0x007fb55e80c378 @tempfile=#<Tempfile:/var/folders/3m/t1v11gzj32n0fdbhwr823y600000gn/T/RackMultipart20141002-33694-3bmoib>, @original_filename="10495567_1510476362523625_7774203923998269219_o.jpg", @content_type="image/jpeg", @headers="Content-Disposition: form-data; name=\"image[file][]\"; filename=\"10495567_1510476362523625_7774203923998269219_o.jpg\"\r\nContent-Type: image/jpeg\r\n">]}}
Completed 500 Internal Server Error in 3ms

TypeError (no implicit conversion of nil into String):
  carrierwave (0.10.0) lib/carrierwave/uploader/cache.rb:159:in `join'
  carrierwave (0.10.0) lib/carrierwave/uploader/cache.rb:159:in `cache_path'
  carrierwave (0.10.0) lib/carrierwave/uploader/cache.rb:131:in `block in cache!'
  carrierwave (0.10.0) lib/carrierwave/uploader/callbacks.rb:17:in `with_callbacks'
  carrierwave (0.10.0) lib/carrierwave/uploader/cache.rb:122:in `cache!'
  carrierwave (0.10.0) lib/carrierwave/mount.rb:329:in `cache'
  carrierwave (0.10.0) lib/carrierwave/mount.rb:163:in `file='
  carrierwave (0.10.0) lib/carrierwave/orm/activerecord.rb:39:in `file='
  activerecord (4.1.5) lib/active_record/attribute_assignment.rb:45:in `public_send'
  activerecord (4.1.5) lib/active_record/attribute_assignment.rb:45:in `_assign_attribute'
  activerecord (4.1.5) lib/active_record/attribute_assignment.rb:32:in `block in assign_attributes'
  activerecord (4.1.5) lib/active_record/attribute_assignment.rb:26:in `each'
  activerecord (4.1.5) lib/active_record/attribute_assignment.rb:26:in `assign_attributes'
  activerecord (4.1.5) lib/active_record/core.rb:455:in `init_attributes'
  activerecord (4.1.5) lib/active_record/core.rb:198:in `initialize'
  activerecord (4.1.5) lib/active_record/inheritance.rb:30:in `new'
  activerecord (4.1.5) lib/active_record/inheritance.rb:30:in `new'
  cancancan (1.9.2) lib/cancan/controller_resource.rb:85:in `build_resource'
  cancancan (1.9.2) lib/cancan/controller_resource.rb:66:in `load_resource_instance'
  cancancan (1.9.2) lib/cancan/controller_resource.rb:32:in `load_resource'
  cancancan (1.9.2) lib/cancan/controller_resource.rb:25:in `load_and_authorize_resource'
  cancancan (1.9.2) lib/cancan/controller_resource.rb:10:in `block in add_before_filter'
  activesupport (4.1.5) lib/active_support/callbacks.rb:440:in `instance_exec'
  activesupport (4.1.5) lib/active_support/callbacks.rb:440:in `block in make_lambda'
  activesupport (4.1.5) lib/active_support/callbacks.rb:160:in `call'
  activesupport (4.1.5) lib/active_support/callbacks.rb:160:in `block in halting'
  activesupport (4.1.5) lib/active_support/callbacks.rb:229:in `call'
  activesupport (4.1.5) lib/active_support/callbacks.rb:229:in `block in halting'
  activesupport (4.1.5) lib/active_support/callbacks.rb:229:in `call'
  activesupport (4.1.5) lib/active_support/callbacks.rb:229:in `block in halting'
  activesupport (4.1.5) lib/active_support/callbacks.rb:166:in `call'
  activesupport (4.1.5) lib/active_support/callbacks.rb:166:in `block in halting'
  activesupport (4.1.5) lib/active_support/callbacks.rb:166:in `call'
  activesupport (4.1.5) lib/active_support/callbacks.rb:166:in `block in halting'
  activesupport (4.1.5) lib/active_support/callbacks.rb:166:in `call'
  activesupport (4.1.5) lib/active_support/callbacks.rb:166:in `block in halting'
  activesupport (4.1.5) lib/active_support/callbacks.rb:86:in `call'
  activesupport (4.1.5) lib/active_support/callbacks.rb:86:in `run_callbacks'
  actionpack (4.1.5) lib/abstract_controller/callbacks.rb:19:in `process_action'
  actionpack (4.1.5) lib/action_controller/metal/rescue.rb:29:in `process_action'
  actionpack (4.1.5) lib/action_controller/metal/instrumentation.rb:31:in `block in process_action'
  activesupport (4.1.5) lib/active_support/notifications.rb:159:in `block in instrument'
  activesupport (4.1.5) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
  activesupport (4.1.5) lib/active_support/notifications.rb:159:in `instrument'
  actionpack (4.1.5) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
  actionpack (4.1.5) lib/action_controller/metal/params_wrapper.rb:250:in `process_action'
  activerecord (4.1.5) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
  actionpack (4.1.5) lib/abstract_controller/base.rb:136:in `process'
  actionview (4.1.5) lib/action_view/rendering.rb:30:in `process'
  actionpack (4.1.5) lib/action_controller/metal.rb:196:in `dispatch'
  actionpack (4.1.5) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'
  actionpack (4.1.5) lib/action_controller/metal.rb:232:in `block in action'
  actionpack (4.1.5) lib/action_dispatch/routing/route_set.rb:82:in `call'
  actionpack (4.1.5) lib/action_dispatch/routing/route_set.rb:82:in `dispatch'
  actionpack (4.1.5) lib/action_dispatch/routing/route_set.rb:50:in `call'
  actionpack (4.1.5) lib/action_dispatch/journey/router.rb:71:in `block in call'
  actionpack (4.1.5) lib/action_dispatch/journey/router.rb:59:in `each'
  actionpack (4.1.5) lib/action_dispatch/journey/router.rb:59:in `call'
  actionpack (4.1.5) lib/action_dispatch/routing/route_set.rb:678:in `call'
  warden (1.2.3) lib/warden/manager.rb:35:in `block in call'
  warden (1.2.3) lib/warden/manager.rb:34:in `catch'
  warden (1.2.3) lib/warden/manager.rb:34:in `call'
  rack (1.5.2) lib/rack/etag.rb:23:in `call'
  rack (1.5.2) lib/rack/conditionalget.rb:35:in `call'
  rack (1.5.2) lib/rack/head.rb:11:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/params_parser.rb:27:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/flash.rb:254:in `call'
  rack (1.5.2) lib/rack/session/abstract/id.rb:225:in `context'
  rack (1.5.2) lib/rack/session/abstract/id.rb:220:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/cookies.rb:560:in `call'
  activerecord (4.1.5) lib/active_record/query_cache.rb:36:in `call'
  activerecord (4.1.5) lib/active_record/connection_adapters/abstract/connection_pool.rb:621:in `call'
  activerecord (4.1.5) lib/active_record/migration.rb:380:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
  activesupport (4.1.5) lib/active_support/callbacks.rb:82:in `run_callbacks'
  actionpack (4.1.5) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/reloader.rb:73:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/remote_ip.rb:76:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
  railties (4.1.5) lib/rails/rack/logger.rb:38:in `call_app'
  railties (4.1.5) lib/rails/rack/logger.rb:20:in `block in call'
  activesupport (4.1.5) lib/active_support/tagged_logging.rb:68:in `block in tagged'
  activesupport (4.1.5) lib/active_support/tagged_logging.rb:26:in `tagged'
  activesupport (4.1.5) lib/active_support/tagged_logging.rb:68:in `tagged'
  railties (4.1.5) lib/rails/rack/logger.rb:20:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/request_id.rb:21:in `call'
  rack (1.5.2) lib/rack/methodoverride.rb:21:in `call'
  rack (1.5.2) lib/rack/runtime.rb:17:in `call'
  activesupport (4.1.5) lib/active_support/cache/strategy/local_cache_middleware.rb:26:in `call'
  rack (1.5.2) lib/rack/lock.rb:17:in `call'
  actionpack (4.1.5) lib/action_dispatch/middleware/static.rb:64:in `call'
  rack (1.5.2) lib/rack/sendfile.rb:112:in `call'
  railties (4.1.5) lib/rails/engine.rb:514:in `call'
  railties (4.1.5) lib/rails/application.rb:144:in `call'
  /Users/joel/Library/Application Support/Pow/Versions/0.4.3/node_modules/nack/lib/nack/server.rb:155:in `handle'
  /Users/joel/Library/Application Support/Pow/Versions/0.4.3/node_modules/nack/lib/nack/server.rb:109:in `rescue in block (2 levels) in start'
  /Users/joel/Library/Application Support/Pow/Versions/0.4.3/node_modules/nack/lib/nack/server.rb:106:in `block (2 levels) in start'
  /Users/joel/Library/Application Support/Pow/Versions/0.4.3/node_modules/nack/lib/nack/server.rb:96:in `each'
  /Users/joel/Library/Application Support/Pow/Versions/0.4.3/node_modules/nack/lib/nack/server.rb:96:in `block in start'
  /Users/joel/Library/Application Support/Pow/Versions/0.4.3/node_modules/nack/lib/nack/server.rb:76:in `loop'
  /Users/joel/Library/Application Support/Pow/Versions/0.4.3/node_modules/nack/lib/nack/server.rb:76:in `start'
  /Users/joel/Library/Application Support/Pow/Versions/0.4.3/node_modules/nack/lib/nack/server.rb:12:in `run'
  /Users/joel/Library/Application Support/Pow/Versions/0.4.3/node_modules/nack/bin/nack_worker:4:in `<main>'


  Rendered /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/templates/rescues/_source.erb (0.5ms)
  Rendered /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/templates/rescues/_trace.text.erb (0.5ms)
  Rendered /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/templates/rescues/_request_and_response.text.erb (0.9ms)
  Rendered /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/templates/rescues/diagnostics.erb (16.2ms)

型号

class Picture
  include Mongoid::Document
  include Mongoid::Timestamps

  belongs_to :gallery

  mount_uploader :file, PictureUploader

  def to_jq_upload
    {
      "name" => read_attribute(:file),
      "size" => file.size,
      "url" => file.url,
      "thumb_url" => file.thumb.url,
      #"delete_url" => gallery_picture_path(:id => id),
      "delete_type" => "DELETE" 
    }
  end
end

Controller

class PicturesController < ApplicationController
  load_and_authorize_resource

  before_action :set_picture, only: [:destroy]

  def create
    p_attr = params[:picture]
    p_attr[:file] = params[:picture][:file].first if params[:picture][:file].class == Array

    logger.debug "params = #{params}"
    logger.debug "p_attr = #{p_attr}"

    @picture = Picture.new(p_attr)

    if @picture.save
      respond_to do |format|
        format.js
        format.html {  
          render :json => [@picture.to_jq_upload].to_json, 
          :content_type => 'text/html',
          :layout => false
        }
        format.json {  
          render :json => { :files => [@picture.to_jq_upload] }     
        }
      end
    else 
      render :json => [{:error => "custom_failure"}], :status => 304
    end
  end

  private

  def picture_params
      params.require(:picture).permit(:gallery_id, file:[])
  end

表单

    <%= form_for Picture.new, :html => { :multipart => true, :id => "fileupload" } do |fm| %>
            <%= fm.file_field :file, :id => "add_images_field", :multiple => true %>
    <% end %>

gem 文件

gem 'rails', '4.1.5'
gem 'mongoid', '~> 4.0.0'
gem 'bson_ext'
gem 'carrierwave-mongoid', :require => 'carrierwave/mongoid'
gem 'mini_magick'
gem 'fog'
gem "jquery-fileupload-rails"

Answer 1

快速浏览一下，我会说您的 picture_params 设置不正确；至少基于 POST 提交字符串。 "file"嵌套在“图像”下，它不在哈希的根级别。

Rails 4 - Strong Parameters - Nested Objects

这是您的 POST 字符串的一些视觉格式:

{
"utf8"=>"✓"
"authenticity_token"=>"MPtXrjrQ+dLb67LVD+aYUrMIYfCUBQWLOaOztlB2sSU="
"image"=>{
    "gallery_id"=>"3"
    "file"=>[#<ActionDispatch::Http::UploadedFile:0x007fb55e80c378 @tempfile=#<Tempfile:/var/folders/3m/t1v11gzj32n0fdbhwr823y600000gn/T/RackMultipart20141002-33694-3bmoib>
        @original_filename="10495567_1510476362523625_7774203923998269219_o.jpg"
        @content_type="image/jpeg"
        @headers="Content-Disposition: form-data; name=\"image[file][]\"; filename=\"10495567_1510476362523625_7774203923998269219_o.jpg\"\r\nContent-Type: image/jpeg\r\n">]
}
}

所以你需要的是:

params.require(:picture).permit(:image => [:gallery_id, file: []])

然而，由于您的表单提交哈希与您的模型名称不匹配 - 无论出于何种原因，请尝试:

params.require(:image).permit(:gallery_id, file: [])

编辑:我也很好奇为什么要在 image 中嵌套 file 和 gallery_id 属性。这将改变 rails 将参数分配给模型的方式，也许这就是你得到 nil 的原因。我认为真正的问题是您设置表单的方式。查看您的 routes.rb 文件； URL 以 /images 结尾，但是您的模型是 Picture。您似乎有命名冲突 - 可能在代码的多个区域。