嵌套属性/形式：未经许可的参数

Question

我一直在检查 active record nested attributes docs 和 strong params docs，但我的日志告诉我，所有权和图像仍然不允许使用：

User Load (0.3ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = $1 LIMIT 1  [["id", 1]]
    Unpermitted parameters: ownership, image 

我的嵌套 form_for 有 3 个模型：

= form_for @murals do |f|

  = f.fields_for @ownerships do |owner|
    = owner.label "Artist"
    = owner.collection_select(:user_id, User.where(artist: true), :id, :first_name, { include_blank: "Pick an artist" })

  = f.hidden_field :latitude, id: 'lat'
  = f.hidden_field :longitude, id: 'long'

  = f.fields_for @images do |image|
    = image.label :file, 'Add Image'
    = image.file_field :file
    = image.file_field :file_cache, class: 'hidden'

  =f.submit 'Upload Mural', class: 'btn btn-primary upload-btn'

我的控制器（我也尝试过使用单个 x_attributes: [:xyz] 没有运气）

def create
    @image = current_user.murals.build(mural_params)
    if @image.save
      redirect_to :root
    else
      render :new
    end
  end

  private

    def mural_params
      params.require(:mural).permit(:longitude, :latitude,
                                    image_attributes: [:file, :file_cache ], 
                                    ownership_attributes: [:user_id]
                                   )
    end

图片.rb：

class Image < ActiveRecord::Base
  belongs_to :user
  belongs_to :mural

  mount_uploader :image, MuralUploader
end

所有权.rb

class Ownership < ActiveRecord::Base
  belongs_to :user
  belongs_to :mural
end

用户.rb：

class User < ActiveRecord::Base
  has_many :authentications, dependent: :destroy
  has_many :images
  has_many :ownerships
  has_many :murals, through: :ownerships

  validates :first_name, presence: true

  mount_uploader :avatar, AvatarUploader
end

壁画.rb：

class Mural < ActiveRecord::Base
  has_many :ownerships
  has_many :images
  has_many :users, through: :ownership
  accepts_nested_attributes_for :ownerships, :images
end

Answer 1

您需要使用accepts_nested_attributes_for 启用嵌套属性更新。

class Mural < ActiveRecord::Base
  ...
  accepts_nested_attributes_for :images, :ownerships
  ...
end

更多详情请见http://api.rubyonrails.org/classes/ActiveRecord/NestedAttributes/ClassMethods.html。