mongo-ruby-driver/lib/mongo/mongo.rb

114 lines
3.7 KiB
Ruby

# --
# Copyright (C) 2008-2009 10gen Inc.
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU Affero General Public License, version 3, as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License
# for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
# ++
require 'mongo/db'
module XGen
module Mongo
module Driver
# Represents a Mongo database server.
class Mongo
DEFAULT_PORT = 27017
# Either nodes_or_host is a host name string and port is an optional
# port number that defaults to DEFAULT_PORT, or nodes_or_host is an
# array of arrays, where each is a host/port pair (or a host with no
# port). Finally, if nodes_or_host is nil then host is 'localhost' and
# port is DEFAULT_PORT. Since that's so confusing, here are a few
# examples:
#
# Mongo.new # localhost, DEFAULT_PORT
# Mongo.new("localhost") # localhost, DEFAULT_PORT
# Mongo.new("localhost", 3000) # localhost, 3000
# Mongo.new([["localhost"]]) # localhost, DEFAULT_PORT
# Mongo.new([["localhost", 3000]]) # localhost, 3000
# Mongo.new([["db1.example.com", 3000], ["db2.example.com", 3000]]])
#
# When a DB object first connects, it tries nodes and stops at the
# first one it connects to.
def initialize(nodes_or_host=nil, port=nil)
@nodes = case nodes_or_host
when String
[[nodes_or_host, port || DEFAULT_PORT]]
when Array
nodes_or_host.collect { |nh| [nh[0], nh[1] || DEFAULT_PORT] }
when nil
[['localhost', DEFAULT_PORT]]
end
end
# Return the XGen::Mongo::Driver::DB named +db_name+. See DB#new for
# +options+.
def db(db_name, options={})
XGen::Mongo::Driver::DB.new(db_name, @nodes, options)
end
# Returns a hash containing database names as keys and disk space for
# each as values.
def database_info
doc = single_db_command('admin', :listDatabases => 1)
h = {}
doc['databases'].each { |db|
h[db['name']] = db['sizeOnDisk'].to_i
}
h
end
# Returns an array of database names.
def database_names
database_info.keys
end
# Not implemented.
def clone_database(from)
raise "not implemented"
end
# Not implemented.
def copy_database(from_host, from_db, to_db)
raise "not implemented"
end
# Drops the database +name+.
def drop_database(name)
single_db_command(name, :dropDatabase => 1)
end
protected
# Send cmd (a hash, possibly ordered) to the admin database and return
# the answer. Raises an error unless the return is "ok" (DB#ok?
# returns +true+).
def single_db_command(db_name, cmd)
db = nil
begin
db = db(db_name)
doc = db.db_command(cmd)
raise "error retrieving database info: #{doc.inspect}" unless db.ok?(doc)
doc
ensure
db.close if db
end
end
end
end
end
end