Heroku 错误 - NameError: 未初始化的常量 PracticeApp::Application::Mongoid

Question

我的应用程序在本地工作，但我在尝试将其推送到 Heroku 时遇到问题。我在我的 Rails 5 应用程序中使用 mLab 和 Mongoid。当我进入时：

git push heroku 大师

我收到以下错误：

r.rb:102:in `load_rake_tasks!': Could not detect rake tasks (LanguagePack::Helpers::RakeRunner::CannotLoadRakefileError)
remote: ensure you can run `$ bundle exec rake -P` against your app
remote: and using the production group of your Gemfile.
remote: rake aborted!
remote: NameError: uninitialized constant PracticeApp::Application::Mongoid
remote: /tmp/build_7a8e6644d3ecbd6336fe612855f87f95/practice_app/config/application.rb:21:in `<class:Application>'
remote: /tmp/build_7a8e6644d3ecbd6336fe612855f87f95/practice_app/config/application.rb:20:in `<module:PracticeApp>'
remote: /tmp/build_7a8e6644d3ecbd6336fe612855f87f95/practice_app/config/application.rb:19:in `<top (required)>'
remote: /tmp/build_7a8e6644d3ecbd6336fe612855f87f95/practice_app/Rakefile:4:in `require_relative'
remote: /tmp/build_7a8e6644d3ecbd6336fe612855f87f95/practice_app/Rakefile:4:in `<top (required)>'

bundle exec rake -P 工作正常。

这是我的 config/application.rb 文件：

require_relative 'boot'

require "rails"
# Pick the frameworks you want:
require "active_model/railtie"
require "active_job/railtie"
# require "active_record/railtie"
require "action_controller/railtie"
require "action_mailer/railtie"
require "action_view/railtie"
require "action_cable/engine"
require "sprockets/railtie"
require "rails/test_unit/railtie"

# Require the gems listed in Gemfile, including any gems
# you've limited to :test, :development, or :production.
Bundler.require(*Rails.groups)

module PracticeApp
  class Application < Rails::Application
    Mongoid.load!("./config/mongoid.yml", :production)
  end
end

我的 rakefile：

require_relative 'config/application'

Rails.application.load_tasks

如果需要，这里是 mongoid.yml 的生产部分：

# mongoid
#
production:
  clients:
    default:
     uri: mongodb://<username>:<password>@ds133340.mlab.com:33340/okclone

     options:
       connect_timeout: 15

注意：我在上面的 uri 中输入了我的实际用户名和密码。

还有我的 gemfile，以防万一：

source 'https://rubygems.org'

gem 'rails',        '5.0.1'
gem 'puma',         '3.4.0'
gem 'sass-rails',   '5.0.6'
gem 'uglifier',     '3.0.0'
gem 'coffee-rails', '4.2.1'
gem 'jquery-rails', '4.1.1'
gem 'turbolinks',   '5.0.1'
gem 'jbuilder',     '2.4.1'

group :development, :test do
  gem 'mongoid', '~> 6.1.0'
  gem 'bson_ext'
  gem 'byebug',  '9.0.0', platform: :mri
end

group :development do
  gem 'web-console',           '3.1.1'
  gem 'listen',                '3.0.8'
  gem 'spring',                '1.7.2'
  gem 'spring-watcher-listen', '2.0.0'
end

group :test do
  gem 'rails-controller-testing', '0.1.1'
  gem 'minitest-reporters',       '1.1.9'
  gem 'guard',                    '2.13.0'
  gem 'guard-minitest',           '2.4.4'
end

group :production do
  gem 'rails_12factor'
end

# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

编辑：我也尝试过运行

heroku 配置：设置 PROD_MONGODB = mongodb://dbuser:dbpass@host1:port1,host2:port2/dbname

添加了我的 mLab URI，但这似乎无法解决问题。

Answer 1

问题出在我的 gemfile 上。因为 mongoid 和 bson gem 只是在测试和开发中，所以它们在生产中是不可访问的。这是更新后的 gemfile：

    source 'https://rubygems.org'

    gem 'rails',        '5.0.1'
    gem 'puma',         '3.4.0'
    gem 'sass-rails',   '5.0.6'
    gem 'uglifier',     '3.0.0'
    gem 'coffee-rails', '4.2.1'
    gem 'jquery-rails', '4.1.1'
    gem 'turbolinks',   '5.0.1'
    gem 'jbuilder',     '2.4.1'
    gem 'mongoid', '~> 6.1.0'
    gem 'bson_ext'

    group :development, :test do
      gem 'byebug',  '9.0.0', platform: :mri
    end

    group :development do
      gem 'web-console',           '3.1.1'
      gem 'listen',                '3.0.8'
      gem 'spring',                '1.7.2'
      gem 'spring-watcher-listen', '2.0.0'
    end

    group :test do
      gem 'rails-controller-testing', '0.1.1'
      gem 'minitest-reporters',       '1.1.9'
      gem 'guard',                    '2.13.0'
      gem 'guard-minitest',           '2.4.4'
    end

    group :production do
      gem 'rails_12factor'
    end

    # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
    gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]