Question

我是一名新的铁杆学生，负责一个有用户登录的项目，每个用户都有一个列表，每个列表都有很多项目。项目嵌套在我的路线中的列表下。

我遇到了一些问题。我的代码下面为该用户加载了一个用户和一个列表，但无法为列表加载项目。我的想法是首先让它工作，但最后我想拥有5个用户，每个用户都有一个列表，每个列表上有15个项目都是由faker创建的。任何帮助表示赞赏。

require 'faker'

# Create an admin user
admin = User.new(
  name:     'Admin User',
  email:    'admin@example.com',
  password: 'helloworld'
)
admin.skip_confirmation!
admin.save!

# Create List
1.times do
  List.create(
    user: admin,
    title: 'Admin List'
  )
end

# Create Items
15.times do
  Item.create(
    list: 'Admin List',
    name: Faker::Company.bs
  )
end

puts "Seed finished"
puts "#{User.count} users created"
puts "#{List.count} lists created"
puts "#{Item.count} items created"

这是完整的错误

heidi-golds-imac:blocitoff dale$ rake db:seed
rake aborted!
ActiveRecord::AssociationTypeMismatch: List(#70281090559180) expected, got    String(#70281054267240)
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/associations/association.rb:216:in  `raise_on_type_mismatch!'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/associations/belongs_to_association.rb:12:in `replace'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/associations/singular_association.rb:17:in `writer'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-  4.2.0/lib/active_record/associations/builder/association.rb:123:in `list='
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/attribute_assignment.rb:54:in `public_send'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/attribute_assignment.rb:54:in `_assign_attribute'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord- 4.2.0/lib/active_record/attribute_assignment.rb:41:in `block in    assign_attributes'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord- 4.2.0/lib/active_record/attribute_assignment.rb:35:in `each'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord- 4.2.0/lib/active_record/attribute_assignment.rb:35:in `assign_attributes'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/core.rb:557:in `init_attributes'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/core.rb:280:in `initialize'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/inheritance.rb:61:in `new'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/inheritance.rb:61:in `new'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord-4.2.0/lib/active_record/persistence.rb:33:in `create'
/Users/dale/code/blocitoff/db/seeds.rb:22:in `block in <top (required)>'
/Users/dale/code/blocitoff/db/seeds.rb:21:in `times'
/Users/dale/code/blocitoff/db/seeds.rb:21:in `<top (required)>'
/usr/local/rvm/gems/ruby-2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:268:in `load'
/usr/local/rvm/gems/ruby-2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:268:in `block in load'
/usr/local/rvm/gems/ruby-2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:240:in `load_dependency'
/usr/local/rvm/gems/ruby-2.2.0/gems/activesupport-4.2.0/lib/active_support/dependencies.rb:268:in `load'
/usr/local/rvm/gems/ruby-2.2.0/gems/railties- 4.2.0/lib/rails/engine.rb:547:in `load_seed'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord- 4.2.0/lib/active_record/tasks/database_tasks.rb:250:in `load_seed'
/usr/local/rvm/gems/ruby-2.2.0/gems/activerecord- 4.2.0/lib/active_record/railties/databases.rake:180:in `block (2 levels) in <top  (required)>'
Tasks: TOP => db:seed
(See full trace by running task with --trace)

项目控制器

class ItemsController < ApplicationController
  before_action :find_list

  def create
    @item = @list.items.build(params.require(:item).permit(:name))

    unless @item.save
      flash[:error] = "There was an error. Please try again."
    end

    redirect_to @list
  end

  private

  def find_list
    @list = List.find(params[:list_id])
  end
end

列出控制器

 class ListsController < ApplicationController

 before_action :authenticate_user! # users must be signed in before any     lists_controller method

  def show
    @list = current_user.list
  end

  def new
    @list = List.new
  end

  def create
     @list = current_user.build_list(params.require(:list).permit(:title,  :body))
     if @list.save
       flash[:notice] = "List was saved."
       redirect_to @list
     else
       flash[:error] = "There was an error. Please try again."
       render :new
     end
   end

  def edit
    @list = List.find(params[:id])
  end

  def update
     @list = List.find(params[:id])
     if @list.update_attributes(params.require(:list).permit(:title, :body))
       flash[:notice] = "List was updated."
       redirect_to @list
     else
       flash[:error] = "There was an error. Please try again."
       render :edit
     end
   end
end

Answer 1

尝试更正以下代码：

# Create Items
15.times do
  Item.create(
    list: 'Admin List'
    name: Faker::Company.bs
  )
end

只需在列表后添加逗号：＆＃39;管理员列表＆＃39; 如果这不能解决问题，请发布完整的错误消息并指定您收到错误的行。

Answer 2

问题是因为您是按名称而不是通过引用将列表分配给项目。在您创建列表的代码块中，您需要将其分配给变量：

list = List.create ...，

然后，在创建项目时，您需要执行以下操作：

Item.create（list：list ....

您正在使用列表的标题，它正在寻找列表对象。

Faker种子数据编码错误

2 个答案: