[エラー]uninitialized constant User (call 'User.connection' to establish a connection)::Image

Question

Carriawaveを導入しようとする中、確認のために新規登録画面から登録しリダイレクトするときに以下のようなエラーが発生しました。

uninitialized constant User (call 'User.connection' to establish a connection)::ImageUploader

こちらのエラーの特徴として、routesにdevise_for :users　という記述がありますが、これを消すとエラーが一旦消えます。

　しかし、入れ違いで以下のようなエラーが発生します。こちらは、devise_for :usersがないと発生します。

undefined method `user_signed_in?' for #<#<Class:0x00007f9892ace2c0>:0x00007f9892acc358>

試した方法:　config/environment.rbの末尾に次のコードを挿入しましたが変化はありませんでした。

require 'carrierwave/orm/activerecord'

<routes.rb>

Rails.application.routes.draw do
 
  resources 'users'
  devise_for :users 
  # For details on the DSL available within this file, see https://guides.rubyonrails.org/routing.html
  root to: 'home#index'

  resources :mypage, only: [:profile] do
    member do
      get 'profile' 
    end
  end

end

<user.rb>

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

end

<uploaders/profile_image_image.uploader.rb>

class ProfileImageUploader < CarrierWave::Uploader::Base
  # Include RMagick or MiniMagick support:
  # include CarrierWave::RMagick
  include CarrierWave::MiniMagick
  process resize_to_fit: [100, 100]

  # Choose what kind of storage to use for this uploader:
  storage :file
  # storage :fog

  # Override the directory where uploaded files will be stored.
  # This is a sensible default for uploaders that are meant to be mounted:
  def store_dir
    "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
  end

  # Provide a default URL as a default if there hasn't been a file uploaded:
  # def default_url(*args)
  #   # For Rails 3.1+ asset pipeline compatibility:
  #   # ActionController::Base.helpers.asset_path("fallback/" + [version_name, "default.png"].compact.join('_'))
  #
  #   "/images/fallback/" + [version_name, "default.png"].compact.join('_')
  # end

  # Process files as they are uploaded:
  # process scale: [200, 300]
  #
  # def scale(width, height)
  #   # do something
  # end

  # Create different versions of your uploaded files:
  # version :thumb do
  #   process resize_to_fit: [50, 50]
  # end

  # Add a white list of extensions which are allowed to be uploaded.
  # For images you might use something like this:
  # def extension_whitelist
  #   %w(jpg jpeg gif png)
  # end

  # Override the filename of the uploaded files:
  # Avoid using model.id or version_name here, see uploader/store.rb for details.
  # def filename
  #   "something.jpg" if original_filename
  # end
end

Answer 1

エラーメッセージの通り、ImageUploaderが存在しません。

ProfileImageUploaderを作ったのでしたら、mount_uploaderでそれを指定すべきなのではないでしょうか？

Comments

[YutoKubo]

'mount_uploaderでそれを指定すべき・・'
<user.rb>の　mount_uploader :profile_image, ImageUploader　のことではないのでしょうか？
ちゃんとあると思うのですが。。

Answer 2

クラス名ProfileImageUploaderをmountして
mount_uploader :profile_image, ProfileImageUploader　
とすることで解決しました。