尽管在下一行中明确定义了该方法，但我遇到了以下错误。
undefined method `before_filter' for AuthorsController:Class
我正在关注本教程。
代码片段如下：
authors_controller.rb
class AuthorsController < ApplicationController
before_action :set_author, only: [:show, :edit, :update, :destroy]
before_filter :zero_authors_or_authenticated, only: [:new, :create]
def zero_authors_or_authenticated
# If either one of them is true this filter won’t do anything, allowing the requested user registration form to be rendered
unless Author.count == 0 || current_user # checking if there are either zero registered users OR if there is a user already logged in
redirect_to root_path # if neither are true, then redirect to root_path and return false
return false
end
end
# GET /authors
# GET /authors.json
def index
@authors = Author.all
end
# GET /authors/1
# GET /authors/1.json
def show
end
# GET /authors/new
def new
@author = Author.new
end
# GET /authors/1/edit
def edit
end
# POST /authors
# POST /authors.json
def create
@author = Author.new(author_params)
respond_to do |format|
if @author.save
format.html { redirect_to @author, notice: 'Author was successfully created.' }
format.json { render :show, status: :created, location: @author }
else
format.html { render :new }
format.json { render json: @author.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /authors/1
# PATCH/PUT /authors/1.json
def update
respond_to do |format|
if @author.update(author_params)
format.html { redirect_to @author, notice: 'Author was successfully updated.' }
format.json { render :show, status: :ok, location: @author }
else
format.html { render :edit }
format.json { render json: @author.errors, status: :unprocessable_entity }
end
end
end
# DELETE /authors/1
# DELETE /authors/1.json
def destroy
@author.destroy
respond_to do |format|
format.html { redirect_to authors_url, notice: 'Author was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_author
@author = Author.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def author_params
params.require(:author).permit(:username, :email, :password, :password_confirmation)
end
end
使用 Sorcery 作为身份验证，windows 10，可视代码。