rails3 使用 mongoid的步骤

mongodb官方的文档(http://www.mongodb.org/display/DOCS/Rails+3+-+Getting+Started)是专门为"mongomapper"准备的。不适用于"mongoid"，所以，大家不要看了。

参考mongoid的官方文档：http://mongoid.org/

1.在Gemfile中增加：

gem "mongoid", "~> 2.4"
  gem "bson_ext", "~> 1.5"

2.$railsgmongoid:config

会生成config/mongoid.yml，形如：

development:
  host: localhost
  database: miaomiao_cat_development

test:
  host: localhost
  database: miaomiao_cat_test

# set these environment variables on your prod server
production:
  host: localhost
  database: miaomiaocat_production

3.编辑config/application.rb

删掉：

require 'rails/all'

增加：

require "action_controller/railtie"
require "action_mailer/railtie"
require "active_resource/railtie"
require "rails/test_unit/railtie"
# require "sprockets/railtie" # Uncomment this line for Rails 3.1+

4.把development.rb,test.rb中，下面2行去掉：

5.去掉spec_helper.rb中的：

(以下步骤就可以参考mongoid官方文档了）

6.建立任意一个model.注意这个include

class Apple
    include Mongoid::Document
    #...
  end