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

74 lines
2.6 KiB
Ruby

# --
# Copyright (C) 2008-2009 10gen Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ++
require 'mongo/message/message'
require 'mongo/message/opcodes'
require 'mongo/util/ordered_hash'
module Mongo
class QueryMessage < Message
attr_reader :query
def initialize(db_name, collection_name, query)
super(OP_QUERY)
@query = query
write_int(0)
write_string("#{db_name}.#{collection_name}")
write_int(query.number_to_skip)
write_int(-query.number_to_return) # Negative means hard limit
sel = query.selector
if query.contains_special_fields
sel = OrderedHash.new
sel['query'] = query.selector
if query.order_by && query.order_by.length > 0
sel['orderby'] = case query.order_by
when String
{query.order_by => 1}
when Array
h = OrderedHash.new
query.order_by.each { |ob|
case ob
when String
h[ob] = 1
when Hash # should have one entry; will handle all
ob.each { |k,v| h[k] = v }
else
raise "illegal query order_by value #{query.order_by.inspect}"
end
}
h
when Hash # Should be an ordered hash, but this message doesn't care
query.order_by
else
raise "illegal order_by: is a #{query.order_by.class.name}, must be String, Array, Hash, or OrderedHash"
end
end
sel['$hint'] = query.hint if query.hint && query.hint.length > 0
sel['$explain'] = true if query.explain
sel['$snapshot'] = true if query.snapshot
end
write_doc(sel)
write_doc(query.fields) if query.fields
end
def first_key(key)
@first_key = key
end
end
end