未定义方法 `before_filter'。

Question

尽管该方法在下一行中明确定义，但我仍然遇到了以下错误。

undefined method `before_filter' for AuthorsController:Class

我正在按照教程进行操作。

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，Visual Code。

- Carrein

---

你正在使用哪个版本的Rails？ - 31piy

Rails 5.1.2，谢谢提醒，我之前不知道 before_filter 已经被弃用了。 - Carrein

before_action 和 before_filter 没有区别，只是 before_filter 已被弃用或移除。请使用 before_action。 - SteveTurczyn

Answer 1

尝试使用 <\p>

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

与其

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

before_filter在Rails 5.0中已被弃用，并在5.1中删除。

- Nimish Gupta

---

这不在5.0迁移指南里，感觉有点奇怪？ - Meekohi

@Meekohi 请查看此链接：http://guides.rubyonrails.org/5_0_release_notes.html#deprecations - Nimish Gupta

Answer 2

如果您在Rails版本＜5中遇到此错误，请检查您的控制器是否从Action Controller继承。

class AuthorsController < ApplicationController
end

- Supertracer

Answer 3

milai在Rails 5.2版本的设置

Gemfile:

• gem 'devise'：身份验证工具
• gem 'milia': 多租户引擎

应用控制器（Application Controller）：

class ApplicationController < ActionController::Base
  before_action :authenticate_tenant! 
end

devise_permitted_parameter.rb:

  included do
    before_filter :configure_permitted_parameters
  end

将上述内容更改为

included do
    before_action :configure_permitted_parameters
  end

运行命令： rails g milia:install --org_email='[e-mail]'

重要提示：当被问及是否覆盖devise_permitted_parameter.rb文件时，请选择“否”(N)。

- Rohit Ghotkar