当我运行'rails g'时，我收到此错误（我的应用似乎运行良好 否则，但我需要使用发电机）：
/home/love/mongodb.roger/.bundler/ruby/1.8/gems/activesupport-3.0.9/lib/active_support/inflector/methods.rb:113:in `constantize': uninitialized constant Rack::Mongoid (NameError)
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/activesupport-3.0.9/lib/active_support/inflector/methods.rb:112:in `each'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/activesupport-3.0.9/lib/active_support/inflector/methods.rb:112:in `constantize'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/actionpack-3.0.9/lib/action_dispatch/middleware/stack.rb:14:in `klass'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/actionpack-3.0.9/lib/action_dispatch/middleware/stack.rb:33:in `build'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/actionpack-3.0.9/lib/action_dispatch/middleware/stack.rb:79:in `build'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/application.rb:209:in `inject'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/actionpack-3.0.9/lib/action_dispatch/middleware/stack.rb:79:in `each'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/actionpack-3.0.9/lib/action_dispatch/middleware/stack.rb:79:in `inject'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/actionpack-3.0.9/lib/action_dispatch/middleware/stack.rb:79:in `build'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/application.rb:162:in `build_middleware_stack'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/application/finisher.rb:35
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/initializable.rb:25:in `instance_exec'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/initializable.rb:25:in `run'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/initializable.rb:50:in `run_initializers'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/initializable.rb:49:in `each'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/initializable.rb:49:in `run_initializers'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/application.rb:134:in `initialize!'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/application.rb:77:in `send'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/application.rb:77:in `method_missing'
from /home/love/mongodb.roger/config/environment.rb:7
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/application.rb:103:in `require_environment!'
from /home/love/mongodb.roger/.bundler/ruby/1.8/gems/railties-3.0.9/lib/rails/commands.rb:16
from script/rails:6:in `require'
from script/rails:6
我使用1.8.7（但是当我使用1.9.x和RVM时我也会收到此错误）。
ruby -v
ruby 1.8.7 (2010-08-16 patchlevel 302) [x86_64-linux]
rails -v
Rails 3.0.9
cat Gemfile
source 'http://rubygems.org'
gem 'rails', '3.0.9'
gem "mongoid", "~> 2.1.0"
gem "bson_ext", "~> 1.3"
gem "devise" #, :git=>"https://github.com/plataformatec/devise.git"
gem "rails-footnotes", ">= 3.7", :group => :development
gem "compass"
gem 'SystemTimer'
gem "oa-oauth", :require => "omniauth/oauth"
gem "warden"
gem 'formtastic', '~> 1.1.0'
gem 'paperclip'
gem 'jquery-rails'
gem 'acts-as-taggable-on'
gem "gmaps4rails"
gem 'browser'
gem 'apotomo', "~>1.1.0"
gem 'sass'
gem 'chunky_png'
gem 'mongoid-paperclip'
有没有人有任何想法？
答案 0 :(得分：8)
从config/application.rb文件中删除该行：
require "mongoid/railtie"
答案 1 :(得分：2)
在使用Mongoid时，我已经看到了从Rails 3.0.7迁移到Rails 3.1.3的这个问题。要解决这个问题，请找到你正在做的所有mongoid需要的地方 - 例如 - 在config / application.rb
require 'mongoid/railtie'
require 'action_controller/railtie'
require 'action_mailer/railtie'
require 'active_resource/railtie'
require 'rails/test_unit/railtie'
...然后在此之前添加require'chack / mongoid'给你......
require 'rack/mongoid' # TADA!
require 'mongoid/railtie'
require 'action_controller/railtie'
require 'action_mailer/railtie'
require 'active_resource/railtie'
require 'rails/test_unit/railtie'
这也让Rails控制台也为我工作（rails c）