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# frozen_string_literal: true
# rubocop:todo all
# Copyright (C) 2021 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
class Cluster
module Topology
# Defines behavior for when a cluster is in load-balanced topology.
class LoadBalanced < Base
# The display name for the topology.
NAME = 'LoadBalanced'.freeze
# Get the display name.
#
# @return [ String ] The display name.
def display_name
self.class.name.gsub(/.*::/, '')
end
# @note This method is experimental and subject to change.
#
# @api experimental
def summary
details = server_descriptions.keys.join(',')
"#{display_name}[#{details}]"
end
# Determine if the topology would select a readable server for the
# provided candidates and read preference.
#
# @param [ Cluster ] cluster The cluster.
# @param [ ServerSelector ] server_selector The server
# selector.
#
# @return [ true ] A standalone always has a readable server.
def has_readable_server?(cluster, server_selector = nil); true; end
# Determine if the topology would select a writable server for the
# provided candidates.
#
# @param [ Cluster ] cluster The cluster.
#
# @return [ true ] A standalone always has a writable server.
def has_writable_server?(cluster); true; end
# Returns whether this topology is one of the replica set ones.
#
# @return [ false ] Always false.
def replica_set?; false; end
# Select appropriate servers for this topology.
#
# @param [ Array<Server> ] servers The known servers.
#
# @return [ Array<Server> ] All of the known servers.
def servers(servers, name = nil)
servers
end
# Returns whether this topology is sharded.
#
# @return [ false ] Always false.
def sharded?; false; end
# Returns whether this topology is Single.
#
# @return [ true ] Always false.
def single?; false; end
# Returns whether this topology is Unknown.
#
# @return [ false ] Always false.
def unknown?; false; end
private
def validate_options(options, cluster)
if cluster.servers_list.length > 1
raise ArgumentError, "Cannot instantiate a load-balanced topology with more than one server in the cluster: #{cluster.servers_list.map(&:address).map(&:seed).join(', ')}"
end
super(options, cluster)
end
end
end
end
end
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