ruby - irb 无权访问我的模型(NameError : uninitialized constant)

Question

我在 IRB 中尝试创建新的“Pin”时收到此错误。例如:

irb(main):001:0> @pin = Pin.first
NameError: uninitialized constant Pin

或

irb(main):001:0> @pin = Pin.new
NameError: uninitialized constant Pin

我必须改变一些东西，因为它以前是有效的。不幸的是，我找不到错误

这是我的引脚 Controller :

  class PinsController < ApplicationController
  before_action :authenticate_user!, except: [:index, :show]
  before_action :correct_user, only: [:edit, :update, :destroy]
  before_action :set_pin, only: [:show, :edit, :update, :destroy]

  def index
    @pins = Pin.all
  end

  def show
    @pin = Pin.find params[:id]
  end

  def new
    @pin = Pin.new
  end

  def edit
  end

  def create
    @pin = Pin.new(pin_params)
    if @pin.save
      redirect_to @pin, notice: 'Pin was successfully created.'
    else
      render action: 'new'
    end
  end

  def update
    if @pin.update(pin_params)
      redirect_to @pin, notice: 'Pin was successfully updated.'
    else
      render action: 'edit'
    end
  end

  def destroy
    @pin.destroy
    redirect_to pins_url
  end

  private

  # Use callbacks to share common setup or constraints between actions.
  def set_pin
    @pin = Pin.find(params[:id])
  end

  def correct_user
    @pin = current_user.pins.find(params[:id])
    redirect_to pins_path, notice: "Not allowed!" if @pin.nil?
  end

  # Never trust parameters from the scary internet, only allow the white list through.
  def pin_params
    params.require(:pin).permit(:description)
  end
end

这是我的联想，pin.rb

class Pin < ApplicationRecord
  belongs_to :user
end

还有我对 User.rb 的联想:

class User < ApplicationRecord
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable

  has_many :pins
end

和我的路线

Rails.application.routes.draw do
  resources :pins
  devise_for :users
  root "pages#home"

  get "about" => "pages#about"

end  

Answer 1

irb 不会自动加载您的 Rails 环境，这就是为什么它无法访问您的模型(或助手、数据库或其他任何东西)的原因。但是，“rails 控制台”是一个 irb session ，它会加载所有 Rails 类、数据库连接等。

启动 Rails 控制台:

rails c

这是以下内容的简写:

rails console

这将为您的开发环境启动 Rails 控制台。你可以让它连接到你的测试环境:

rails c RAILS_ENV=test

或您的生产环境:

rails c RAILS_ENV=production