为什么在我的 config/application.rb 中没有安装/需要“require 'rails/all'”？

Question

这只是一个奇怪的刺激，但为什么我的应用程序没有在 config/application.rb 或其他任何地方包含预期的行？

require 'rails/all' 

这个应用程序是在 2014 年初使用 Rails Composer 生成的，如果这有所不同的话。此外，它是 Rails 4.2.1。

出现这个问题只是因为我正在研究配置 Rails 应用程序和Rails 初始化过程指南，因为我需要修改我的初始化过程。两者都声明 config/application.rb 文件应该包含该行，但我的没有。而且，是的，该应用程序在本地和 Heroku 上运行得很好，所以......为什么？

我的文件是：

require File.expand_path('../boot', __FILE__)

# Pick the frameworks you want:
require "active_record/railtie"
require "action_controller/railtie"
require "action_mailer/railtie"
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(:default, Rails.env)

module Theappname
  class Application < Rails::Application

    config.generators do |g|

      # Enable Chrome Source Maps so CSS and JS can be debugged
      #g.sass_options = { :debug_info => true }

      # don't generate RSpec tests for views and helpers
      g.test_framework :rspec, fixture: true
      g.fixture_replacement :factory_girl, dir: 'spec/factories'

      g.view_specs false
      g.helper_specs false
    end

    # Rails 4 should include all helpers for controllers and views
    config.action_controller.include_all_helpers = true  

    # Settings in config/environments/* take precedence over those specified here.
    # Application configuration should go into files in config/initializers
    # -- all .rb files in that directory are automatically loaded.

    # Set Time.zone default to the specified zone and make Active Record auto-convert to this zone.
    # Run "rake -D time" for a list of tasks for finding time zone names. Default is UTC.
    #config.time_zone = 'Eastern Time (US & Canada)'
    config.time_zone = 'UTC'   # Don't use local time or you won't notice time issues.

    # The default locale is :en and all translations from config/locales/*.rb,yml are auto loaded.
    # config.i18n.load_path += Dir[Rails.root.join('my', 'locales', '*.{rb,yml}').to_s]
    # config.i18n.default_locale = :de

    # Do not check for unavailable locales
    I18n.enforce_available_locales = false

    # not needed at 4.0
    config.assets.initialize_on_precompile = false

    # Load files in lib
    config.autoload_paths += %W(#{config.root}/lib)

    # Extend Rails classes in lib/core_ext/<classname>.rb...  See above?
    #config.autoload_paths += Dir[File.join(Rails.root, "lib", "core_ext", "*.rb")].each {|l| require l }

    # 20150711 Default Date formats
    #default_date_formats = { :default => '%d.%m.%Y' }
    default_date_formats = { :default => '%Y.%m.%d' }
    Time::DATE_FORMATS.merge!(default_date_formats)
    Date::DATE_FORMATS.merge!(default_date_formats)

    # 20150808 Adding Delayed_Job queueing for daily_report and such
    config.active_job.queue_adapter = :delayed_job

  end
end

Answer 1

require 'rails/all'如果这符合您的喜好，您可以，但是这些行需要运行应用程序所需的 rails 部分：

require "active_record/railtie"
require "action_controller/railtie"
require "action_mailer/railtie"
require "sprockets/railtie"

如果我猜测这样做的动机，可能是您不一定需要或想要应用程序中 Rails 的所有部分，因此最好明确要求您想要的部分而不是所有部分。在这种情况下，如果你愿意，require 'rails/all'你最终会得到action_view, active_job, 和rails/test_unit上面的。所需的文件可以在railties.