module Mongo::Cluster::Topology
Defines behavior for getting servers.
Topologies are associated with their clusters - for example, a ReplicaSet topology contains the replica set name. A topology object therefore cannot be used with multiple cluster objects.
At the same time, topology objects do not know anything about specific servers in a cluster, despite what their constructor may suggest. Which means, in particular, that topology change events require the application to maintain cluster references on its own if it wants to track server changes within a replica set.
@since 2.0.0
Constants
- OPTIONS
The various topologies for server selection.
@since 2.0.0 @api private
Public Instance Methods
Get the initial cluster topology for the provided options.
@example Get the initial cluster topology.
Topology.initial(topology: :replica_set)
@param [ Cluster
] cluster The cluster. @param [ Monitoring
] monitoring The monitoring. @param [ Hash ] options The cluster options.
@option options [ true | false ] :direct_connection Whether to connect
directly to the specified seed, bypassing topology discovery. Exactly one seed must be provided.
@option options [ Symbol
] :connect Deprecated - use :direct_connection
option instead of this option. The connection method to use. This forces the cluster to behave in the specified way instead of auto-discovering. One of :direct, :replica_set, :sharded, :load_balanced. If :connect is set to :load_balanced, the driver will behave as if the server is a load balancer even if it isn't connected to a load balancer.
@option options [ true | false ] :load_balanced Whether to expect to
connect to a load balancer.
@option options [ Symbol
] :replica_set The name of the replica set to
connect to. Servers not in this replica set will be ignored.
@return [ ReplicaSet, Sharded
, Single
, LoadBalanced
] The topology.
@since 2.0.0 @api private
# File lib/mongo/cluster/topology.rb, line 90 def initial(cluster, monitoring, options) connect = options[:connect]&.to_sym cls = if options[:direct_connection] if connect && connect != :direct raise ArgumentError, "Conflicting topology options: direct_connection=true and connect=#{connect}" end if options[:load_balanced] raise ArgumentError, "Conflicting topology options: direct_connection=true and load_balanced=true" end Single elsif options[:direct_connection] == false && connect && connect == :direct raise ArgumentError, "Conflicting topology options: direct_connection=false and connect=#{connect}" elsif connect && connect != :load_balanced if options[:load_balanced] raise ArgumentError, "Conflicting topology options: connect=#{options[:connect].inspect} and load_balanced=true" end OPTIONS.fetch(options[:connect].to_sym) elsif options.key?(:replica_set) || options.key?(:replica_set_name) if options[:load_balanced] raise ArgumentError, "Conflicting topology options: replica_set/replica_set_name and load_balanced=true" end ReplicaSetNoPrimary elsif options[:load_balanced] || connect == :load_balanced LoadBalanced else Unknown end # Options here are client/cluster/server options. # In particular the replica set name key is different for # topology. # If replica_set_name is given (as might be internally by driver), # use that key. # Otherwise (e.g. options passed down from client), # move replica_set to replica_set_name. if (cls <= ReplicaSetNoPrimary || cls == Single) && !options[:replica_set_name] options = options.dup options[:replica_set_name] = options.delete(:replica_set) end cls.new(options, monitoring, cluster) end