我目前正在设置我的第一个 Mongodb，Rails 4 环境，需要在运行 bundle install 之前配置 gem。这是我的宝石文件。
source 'https://rubygems.org'
# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.0.1'
# User mongoid for database.
gem 'mongoid', github: 'mongoid/mongoid'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 4.0.0'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .js.coffee assets and views
gem 'coffee-rails', '~> 4.0.0'
# See https://github.com/sstephenson/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby
# Use jquery as the JavaScript library
gem 'jquery-rails'
# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
gem 'turbolinks'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 1.2'
group :doc do
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', require: false
end
group :test do
gem 'cucumber-rails', :require => false
gem 'capybara'
#database_cleaner is not required, but highly recommended
gem 'database_cleaner'
end
似乎 Mongo 无法安装，因为我找不到 Mongo:Config 文件。