Ruby on Rails、form_for、回形针和大量指定受保护的参数

Question

我一直在开发一个上传和处理图像的rails应用程序。图像以及其他字符串信息通过form_for提交。我已经研究这个话题大约16个小时了，还没有解决方案。老实说，这就像rails甚至不能读取我的代码。

一个Processmodel有许多资产，其中一个资产只是一个保存一个图像文件的模型。在创建流程模型时，我永远不能访问资产，总是收到无法批量分配属性: assets_attributes

Completed 500 Internal Server Error in 13ms

ActiveModel::MassAssignmentSecurity::Error (Can't mass-assign protected attributes: asset):
  app/controllers/process_controller.rb:20:in `new'
  app/controllers/process_controller.rb:20:in `create'

• 此表单在new.html.erb

中使用

<%= semantic_form_for @processmodel, :url => { :action => 'create' }, :html => {     :multipart => true } do |f| %>
    <%= f.input :batch, :as => :string, :name => "Batch" %>
    <%= f.input :batchset, :as => :string, :name => "Batchset" %>
    <%= f.input :numSlots, :as => :number, :name => "Number of slots" %>    
    <%= f.input :key, :as => :file, :name => "Key" %>   

    <%= f.semantic_fields_for :asset do |asset| %> 
        <%= asset.input :asset, :as => :file, :label => "Image" %>
    <% end %><br />

    <%= f.submit %>
<% end %>

-

class Processmodel < ActiveRecord::Base
  attr_accessible :user_id, :batch, 
                :batchset, :numSlots,
                :key,:assets_attributes

  attr_accessor :key_file_name

  has_many :assets, :dependent => :destroy
  belongs_to :user  
  has_attached_file :key
  #    :url => Rails.root.join('/assets/readimages/:basename.:extension'),
  #    :path => Rails.root.join('/assets/readimages/:basename.:extension'),

  accepts_nested_attributes_for :assets, :allow_destroy => true

  . 
  . 
  .

end

-

require 'RMagick'
class Asset < ActiveRecord::Base
    attr_accessible :results_string, 
        :name, 
        :ambiguous_results, 
        :image 
    belongs_to :batch_element
    belongs_to :processmodel
    has_attached_file :image 
    validates_attachment_presence :image
end

-

class ProcessController < ApplicationController
def create
    @Processmodel = Processmodel.new(params[:processmodel])
    @Processmodel.save    
    all_img = Array.new(@processmodel.assets.all)
    respond_to do |format|
      if @processmodel.beginRead(...)
        redirect_to :action => 'results_main', :controller => 'results' 
      else
        format.html { render action: "new" }
   end
end 
end

-

def new
  @processmodel = Processmodel.new
  #5.times{@processmodel.assets.build}
  respond_to do |format|
    format.html #new.html.erb
end
end

我要求如何解决这个问题，并让我的应用程序工作的想法。

Answer 1

您需要更新数据库迁移。运行：

rails g migration AddIdToAsset processmodel_id:integer
rake db::migrate

Answer 2

您已在此处将附加文件命名为:image：

has_attached_file :image

但在您的视图中，您将其称为:asset：

<%= asset.input :asset, :as => :file, :label => "Image" %>

要进行修复，只需将此行更改为

<%= asset.input :image, :as => :file, :label => "Image" %>