在Rails中我们可以通过MongoMapper来使用MongoDB数据库,下面就来记录一下Ruby on Rails框架程序连接MongoDB的教程,需要的朋友可以参考下
前边有介绍mongodb的安装以及ror项目的搭建，现在进行一下整合。
1.创建项目
创建项目时不再使用rails active_record支持
rails new todo -O
2.我们将要使用MongoMapper来驱动MongoDB到Rails
编辑GemFile，增加下面的内容
gem"mongo_mapper"
然后 执行 bundle install 安装gem
bundle install
3.添加数据库链接
在config/initializer下面新建一个mongo.rb文件，指定全局的数据库信息：
MongoMapper.connection = Mongo::Connection.new('localhost', 27017)
MongoMapper.database ='todo'#通过指定Rails运行环境参数，我们可以在不同的运行环境下创建互不干扰的数据，为了简单起见，没有为不同的环境指定不同的数据
if defined?(PhusionPassenger)
PhusionPassenger.on_event(:starting_worker_process)do|forked|
MongoMapper.connection.connectifforked
完成以上步骤后，启动程序：
$ rails server
**Notice: C extension not loaded. This is required for optimum MongoDB Ruby driver performance.
You can install the extension as follows:
If you continue to receive this message after installing, make sure that the
bson_ext gem is in your load path and that the bson_ext and mongo gems are of the same version.
=> Booting WEBrick
=> Rails 3.0.10 application starting in development on http://0.0.0.0:3000
=> Call with -d to detach
=> Ctrl-C to shutdown server
[2011-10-19 23:36:14] INFO WEBrick 1.3.1
[2011-10-19 23:36:14] INFO ruby 1.9.2 (2011-07-09) [x86_64-linux]
[2011-10-19 23:36:14] INFO WEBrick::HTTPServer#start: pid=19595 port=3000
PS：Ruby编写MongoDB备份脚本(fsync & lock)
#!/usr/local/bin/ruby
# date: 06-12-2014
# auther: lucifer
# use fsync and lock to the file-system before backup the file-system
# mongo-ruby-driver version > 1.10.0
require 'mongo'
require 'fileutils'
require 'date'
include Mongo
include BSON
# the members of replcation-set
# test mongodb server version 2.6.0
# host = "192.168.11.51"
# The port of members
# If the port is 27017 by default then otherport don't need to assignment
# otherport = ""
# port = otherport.length != 0 ? otherport : MongoClient::DEFAULT_PORT
# opts = {:pool_size => 5, :pool_timeout => 10}
# Create a new connection
# client = MongoClient.new(host, port, opts)
uri_string = "mongodb://caoqing:[email protected]:27017/admin"
client = MongoClient.from_uri(uri = "#{uri_string}")
db = client['admin']
# fsync and lock the database
cmd = OrderedHash.new
cmd[:fsync] = 1
cmd[:lock] = true
# p cmd
db.command(cmd)
# datafile path
d = "/var/lib/mongo"
# dir = Dir.new("#{d}")
# entries = dir.entries
# entries.delete_if { |entry| entry =~ /^\./}
# convert the relative path to the full path
# entries.map! { |entry| File.join(dir.path, entry) }
# maintain only the type of file
# entries.delete_if { |entry| !File.file?(entry) }
# p entries
start = Date.today.to_s
prev = (Date.today - 7).to_s
dest = "/backup/#{start}"
sour = "/backup/#{prev}"
FileUtils.rm_rf("#{sour}") if File::exist?("#{sour}")
Dir.mkdir("#{dest}", 0755) unless File::exist?("#{dest}")
FileUtils.cp_r Dir.glob("#{d}/**"), dest if client.locked?
puts "*" * 20
puts "\tbackup complete"
puts "*" * 20
# DB::SYSTEM_COMMAND_COLLECTION
# unlock the database
db["$cmd.sys.unlock"].find_one
client.close
