Question

我正在使用Ruby on Rails 3.0.7，我对更新控制器操作的关联模型验证存在问题。我正在使用“has_many：through”关联，以便我可以处理用户类别关系。

在User模型中我有：

has_many :user_category_relationships,
  :autosave    => true,
  :dependent   => :destroy
has_many :user_categories,
  :through     => :user_category_relationships,
  :source      => :user_category,
  :dependent   => :destroy

在_form视图文件中我有：

<% @current_user.user_categories.each do |user_category| %>
  <%= check_box_tag :user_category_ids, user_category.id, @user.user_categories.include?(user_category), :name => 'user_relationships[user_category_ids][]' %>
  <%= label_tag "user_category_#{user_category.id}", user_category.name %>
<% end %>

在UserCategoryRelationship模型中我有：

belongs_to :users
belongs_to :categories

# Validation
validates :name_id,
  :presence   => true,
  :uniqueness => {
    :scope          => [:created_by_user_id, :category_id]
  }
validates :category_id,
  :presence   => true,
  :uniqueness => {
    :scope          => [:created_by_user_id, :name_id]
  }
validates :created_by_user_id,
  :presence   => true,
  :uniqueness => {
    :scope          => [:category_id, :name_id]
  }

在UsersController我有：

def create
  ...

  # `params[:user_relationships][:user_category_ids]` used below are id values 
  # related to user-category relationships.

  unless params[:user_relationships][:user_category_ids]
    # Set default user category if not selected.
    @user.user_category_relationships.build(
      :category_id        => '1',
      :created_by_user_id => @current_user.id,
      :name_id            => @name.id
    )
  else
    params[:user_relationships][:user_category_ids].each { |user_category_id|
      @user.user_category_relationships.build(
        :category_id        => user_category_id,
        :created_by_user_id => @current_user.id,
        :name_id            => @name.id
      )
    }
  end

  if @user.save
    ...
  end
end

def update
  ...

  # Note: The following code is equal to that in the controller 'create' 
  # action. However here is my problem because validation (read after 
  # for more information about).

  unless params[:user_relationships][:user_category_ids]
    # Set default user category if not selected.
    @user.user_category_relationships.build(
      :category_id        => '1',
      :created_by_user_id => @current_user.id,
      :name_id            => @name.id
    )
  else
    params[:user_relationships][:user_category_ids].each { |user_category_id|
      @user.user_category_relationships.build(
        :category_id        => user_category_id,
        :created_by_user_id => @current_user.id,
        :name_id            => @name.id
      )
    }
  end

  if @user.update_attributes(params[:user])
    ...
  end
end

上述代码除update操作外有效：当我尝试运行时，我总是得到同样的错误，以及。

# Validation errors on updating the 'user_category_relationships' associated model
:"user_category_relationships.category_id"        =>["has already been taken"]
:"user_category_relationships.name_id"            =>["has already been taken"]
:"user_category_relationships.created_by_user_id" =>["has already been taken"]

我想做什么，因为我根本没有使用“RoR魔法\自动方式”（也就是说，我没有使用collection_singular_ids方法 - 请参阅还this和this），是为了正确使用update控制器操作，这样我仍然可以使用“自动”创建用户类别关系 （在save和update_attributes(...)方法上触发）但避免生成上述验证错误（即，在数据库表中创建有效数据）。 我该怎么办？你对这个问题有什么建议？

PS：我遇到麻烦的地方是update行动，准确地弄清楚如何“选择”“过滤”和“编码”记录来更新，创建和删除具有参数的数据库[：user_relationships] [：user_category_ids]作为输入数据。

使用'has_many：through'记录关联更新记录时出现问题

0 个答案: