Undefined method for `before_filter '

Question

I ran into the following error, even though the method is clearly defined in the next line.

undefined method `before_filter' for AuthorsController:Class 

I follow this tutorial .

The code fragment is as follows:

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 

Using Sorcery as Authentication, Windows 10 Visual Code.

Answer 1

Try using

 before_action :zero_authors_or_authenticated, only: [:new, :create] 

Instead

 before_filter :zero_authors_or_authenticated, only: [:new, :create] 

before_filter deprecated in Rails 5.0 and removed in 5.1.

Answer 2

If you get this error on rails 4.2.7, check if you have inherited your controller from the action controller

 class AuthorsController < ApplicationController end