NameError升级到rails 4后，has_many关联的未初始化常量

Question

我尝试将我的rails应用程序升级到4.0.1，我的控制器中出现了一行@ gallery.pictures.build：

NameError in GalleriesController#new
uninitialized constant Gallery::Picture

  @gallery = Gallery.new
  @gallery.token = @gallery.generate_token
  @picture = @gallery.pictures.build
  @pictures = []

除了使用强参数之外，我没有更改任何代码，也无法找出代码破坏的原因。任何帮助将非常感谢！

如果有助于查找错误，可以使用以下代码：

class GalleriesController < ApplicationController
  # GET /galleries
  # GET /galleries.json
  def index
    @galleries = Gallery.all

    respond_to do |format|
      format.html # index.html.erb
      format.json { render json: @galleries }
    end
  end

  # GET /galleries/1
  # GET /galleries/1.json
  def show
    @gallery = Gallery.find(params[:id])
    @picture = @gallery.pictures.build
    @pictures = Picture.find(:all, :conditions  => [ 'gallery_id = ?', @gallery.id ])
    respond_to do |format|
      format.html # show.html.erb
      format.json { render json: @gallery }
    end
  end

  # GET /galleries/new
  # GET /galleries/new.json
  def new
    @gallery = Gallery.new
    @gallery.token = @gallery.generate_token
    @picture = @gallery.pictures.build
    @pictures = []

    respond_to do |format|
      format.html # new.html.erb
      format.json { render json: @gallery }
    end
  end

  # GET /galleries/1/edit
  def edit
    @gallery = Gallery.find(params[:id])
    @picture = @gallery.pictures.build
    @pictures = []
  end

  # POST /galleries
  # POST /galleries.json
  def create
    @gallery = Gallery.new(gallery_params)
    @pictures = Picture.where(:gallery_token => @gallery.token)
    @gallery.pictures << @pictures

    respond_to do |format|
      if @gallery.save
        format.html { redirect_to @gallery, notice: 'Gallery was successfully created.' }
        format.json { render json: @gallery, status: :created, location: @gallery }
      else
        format.html { render action: "new" }
        format.json { render json: @gallery.errors, status: :unprocessable_entity }
      end
    end
  end

  # PUT /galleries/1
  # PUT /galleries/1.json
  def update
    @gallery = Gallery.find(params[:id])

    respond_to do |format|
      if @gallery.update_attributes(gallery_params)
        format.html { redirect_to @gallery, notice: 'Gallery was successfully updated.' }
        format.json { head :no_content }
      else
        format.html { render action: "edit" }
        format.json { render json: @gallery.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /galleries/1
  # DELETE /galleries/1.json
  def destroy
    @gallery = Gallery.find(params[:id])
    @gallery.destroy

    respond_to do |format|
      format.html { redirect_to galleries_url }
      format.json { head :no_content }
    end
  end

  private
    # Use callbacks to share common setup or constraints between actions.
     def set_gallery
        @project = @label.projects.find(params[:id])
     end

    # Use this method to whitelist the permissible parameters. Example:
    #   params.require(:person).permit(:name, :age)
    #
    # Also, you can specialize this method with per-user checking of permissible
    # attributes.
    def gallery_params
      params.require(:gallery).permit(:cover, :description, :name, :token)
    end

end

类PicturesController＆lt; ApplicationController中

  before_action :set_picture, only: [:show, :edit, :update, :destroy]
  # GET /pictures
  # GET /pictures.json
  def index

    @gallery = Gallery.find(params[:gallery_id])

    @pictures = @gallery.pictures

    respond_to do |format|
      format.html # index.html.erb
      format.json { render json: @pictures }
    end
  end

  # GET /pictures/1
  # GET /pictures/1.json
  def show
    @picture = Picture.find(params[:id])

    respond_to do |format|
      format.html # show.html.erb
      format.json { render json: @picture }
    end
  end

  # GET /pictures/new
  # GET /pictures/new.json
  def new
    @gallery = Gallery.find(params[:gallery_id])
    @picture = @gallery.pictures.build

    respond_to do |format|
      format.html # new.html.erb
      format.json { render json: @picture }
    end
  end

  # GET /pictures/1/edit
  def edit
    @gallery = Gallery.find(params[:gallery_id])

    @picture = @gallery.pictures.find(params[:id])
    # @picture = Picture.find(params[:id])
  end

  # POST /pictures
  # POST /pictures.json
  def create
    p_attr = params[:picture]
    Rails.logger.debug("[debug] : #{p_attr}" );
    p_attr[:image] = params[:picture][:image].first if params[:picture][:image].class == Array
    Rails.logger.debug("[debug] : #{p_attr[:image]}" );

    if params[:gallery_id]
      @gallery = Gallery.find(params[:gallery_id])
      @picture = @gallery.pictures.build(p_attr)
    else
      @picture = Picture.new(p_attr)
    end

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

  # PUT /pictures/1
  # PUT /pictures/1.json
  def update

    @gallery = Gallery.find(params[:gallery_id])

    @picture = @gallery.pictures.find(params[:id])

    respond_to do |format|
      if @picture.update_attributes(picture_params)
        format.html { redirect_to gallery_path(@gallery), notice: 'Picture was successfully updated.' }
        format.json { head :no_content }
      else
        format.html { render action: "edit" }
        format.json { render json: @picture.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /pictures/1
  # DELETE /pictures/1.json
  def destroy
    @gallery = Gallery.find(params[:gallery_id])
    @picture = @gallery.pictures.find(params[:id])
    @picture.destroy

    respond_to do |format|
      format.html { redirect_to gallery_pictures_url }
      format.js
    end
  end

  def make_default
    @picture = Picture.find(params[:id])
    @gallery = Gallery.find(params[:gallery_id])

    @gallery.cover = @picture.id
    @gallery.save

    respond_to do |format|
      format.js
    end
  end

  private
    # Use callbacks to share common setup or constraints between actions.
     def set_picture
        @project = @label.projects.find(params[:id])
     end

    # Use this method to whitelist the permissible parameters. Example:
    #   params.require(:person).permit(:name, :age)
    #
    # Also, you can specialize this method with per-user checking of permissible
    # attributes.
    def picture_params
      params.require(:picture).permit(:description, :gallery_id, :image, :crop_x, :crop_y, :crop_w, :crop_h, :gallery_token)
    end
end

class Gallery＆lt;的ActiveRecord ::基

      has_many :pictures, :dependent => :destroy

      def generate_token
        self.token = loop do
          random_token = SecureRandom.urlsafe_base64
          break random_token unless Gallery.where(token: random_token).exists?
        end
      end

    end

class Picture＆lt;的ActiveRecord :: Base的       attr_accessor：crop_x，：crop_y，：crop_w，：crop_h

  belongs_to :gallery

  mount_uploader :image, ImageUploader

  after_update :crop_image

  def to_jq_upload
    {
      "name" => read_attribute(:image),
      "size" => image.size,
      "url" => image.url,
      "thumbnail_url" => image.thumb.url,
      "delete_url" => id,
      "picture_id" => id,
      "delete_type" => "DELETE"
    }
  end

  def crop_image
    image.recreate_versions! if crop_x.present?
    current_version = self.image.current_path
    large_version = "#{Rails.root}/public" + self.image.versions[:large].to_s

    FileUtils.rm(current_version)
    FileUtils.cp(large_version, current_version)
  end
end