lib/mongo/protocol/registry.rb
# frozen_string_literal: true
# rubocop:todo all
# Copyright (C) 2009-2020 MongoDB 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.
module Mongo
module Protocol
# Provides a registry for looking up a message class based on op code.
#
# @since 2.5.0
module Registry
extend self
# A Mapping of all the op codes to their corresponding Ruby classes.
#
# @since 2.5.0
MAPPINGS = {}
# Get the class for the given op code and raise an error if it's not found.
#
# @example Get the type for the op code.
# Mongo::Protocol::Registry.get(1)
#
# @return [ Class ] The corresponding Ruby class for the message type.
#
# @since 2.5.0
def get(op_code, message = nil)
if type = MAPPINGS[op_code]
type
else
handle_unsupported_op_code!(op_code)
end
end
# Register the Ruby type for the corresponding op code.
#
# @example Register the op code.
# Mongo::Protocol::Registry.register(1, Reply)
#
# @param [ Fixnum ] op_code The op code.
# @param [ Class ] type The class the op code maps to.
#
# @return [ Class ] The class.
#
# @since 2.5.0
def register(op_code, type)
MAPPINGS.store(op_code, type)
define_type_reader(type)
end
private
def define_type_reader(type)
type.module_eval <<-MOD
def op_code; OP_CODE; end
MOD
end
def handle_unsupported_op_code!(op_code)
message = "Detected unknown message type with op code: #{op_code}."
raise Error::UnsupportedMessageType.new(message)
end
end
end
end