From 63c91af1b1c4f7cd7525a0197fad9897a0ab2750 Mon Sep 17 00:00:00 2001 From: Kyle Banker Date: Thu, 15 Sep 2011 18:44:02 -0400 Subject: [PATCH] minor fixes and doc updates. :sync is default refresh mode. --- docs/REPLICA_SETS.md | 25 +++++++++++++++-- docs/TAILABLE_CURSORS.md | 2 +- lib/mongo/repl_set_connection.rb | 46 ++++++++++++++++++-------------- lib/mongo/util/pool.rb | 2 +- 4 files changed, 51 insertions(+), 24 deletions(-) diff --git a/docs/REPLICA_SETS.md b/docs/REPLICA_SETS.md index 4818edd..01771f9 100644 --- a/docs/REPLICA_SETS.md +++ b/docs/REPLICA_SETS.md @@ -15,10 +15,10 @@ cache the replica set topology as reported by the given seed node and use that i ### Read slaves -If you want to read from a seconday node, you can pass :read_secondary => true to ReplSetConnection#new. +If you want to read from a secondary node, you can pass :read => :secondary to ReplSetConnection#new. @connection = ReplSetConnection.new(['n1.mydb.net', 27017], ['n2.mydb.net', 27017], ['n3.mydb.net', 27017], - :read_secondary => true) + :read => :secondary) A random secondary will be chosen to be read from. In a typical multi-process Ruby application, you'll have a good distribution of reads across secondary nodes. @@ -32,6 +32,27 @@ If the client decides to retry, it's not guaranteed that another member of the r The driver will essentially cycle through all known seed addresses until a node identifies itself as master. +### Refresh mode + +You can now specify a refresh mode and refresh interval for a replica set connection. This will help to ensure that +changes to a replica set's configuration are quickly reflected on the driver side. Refresh mode is +enabled in synchronous mode by default. Here's how to specify this explicitly: + + @connection = ReplSetConnection.new(['n1.mydb.net', 27017], :refresh_mode => :sync) + +If you want to refresh to happen via a background thread, use the `:async` mode: + + @connection = ReplSetConnection.new(['n1.mydb.net', 27017], :refresh_mode => :async) + +If you want to change the default refresh interval of 90 seconds, you can do so like this: + + @connection = ReplSetConnection.new(['n1.mydb.net', 27017], :refresh_mode => :async, + :refresh_interval => 60) + +You can also disable refresh mode altogether: + + @connection = ReplSetConnection.new(['n1.mydb.net', 27017], :refresh_mode => false) + ### Recovery Driver users may wish to wrap their database calls with failure recovery code. Here's one possibility, which will attempt to connection diff --git a/docs/TAILABLE_CURSORS.md b/docs/TAILABLE_CURSORS.md index 033e595..d526ddf 100644 --- a/docs/TAILABLE_CURSORS.md +++ b/docs/TAILABLE_CURSORS.md @@ -1,4 +1,4 @@ -# Tailable in Ruby +# Tailable cursors in Ruby Tailable cursors are cursors that remain open even after they've returned a final result. This way, if more documents are added to a collection (i.e., diff --git a/lib/mongo/repl_set_connection.rb b/lib/mongo/repl_set_connection.rb index 1bbd10c..6c306a9 100644 --- a/lib/mongo/repl_set_connection.rb +++ b/lib/mongo/repl_set_connection.rb @@ -24,7 +24,7 @@ module Mongo class ReplSetConnection < Connection attr_reader :nodes, :secondaries, :arbiters, :secondary_pools, :replica_set_name, :read_pool, :seeds, :tags_to_pools, - :refresh_interval, :background_refresh + :refresh_interval, :refresh_mode # Create a connection to a MongoDB replica set. # @@ -46,7 +46,7 @@ module Mongo # objects created from this connection object. If +:secondary+ is chosen, reads will be sent # to one of the closest available secondary nodes. If a secondary node cannot be located, the # read will be sent to the primary. - # @option options [Logger, #debug] :logger (nil) Logger instance to receive driver operation log. + # @option options [Logger] :logger (nil) Logger instance to receive driver operation log. # @option options [Integer] :pool_size (1) The maximum number of socket connections allowed per # connection pool. Note: this setting is relevant only for multi-threaded applications. # @option options [Float] :pool_timeout (5.0) When all of the connections a pool are checked out, @@ -57,15 +57,15 @@ module Mongo # @option opts [Float] :connect_timeout (nil) The number of seconds to wait before timing out a # connection attempt. # @option opts [Boolean] :ssl (false) If true, create the connection to the server using SSL. - # @option opts [Boolean] :background_refresh (false) Set this to true to enable a background thread that + # @option opts [Boolean] :refresh_mode (:sync) Set this to :async to enable a background thread that # periodically updates the state of the connection. If, for example, you initially connect while a secondary - # is down, :background_refresh will reconnect to that secondary behind the scenes to - # prevent you from having to reconnect manually. If set to +false+, background refresh will happen - # synchronously. - # @option opts [Integer] :refresh_interval (90) If :background_refresh is enabled, this is the number of seconds - # that the background thread will sleep between calls to check the replica set's state. + # is down, this will reconnect to that secondary behind the scenes to + # prevent you from having to reconnect manually. If set to :sync, refresh will happen + # synchronously. If +false+, no automatic refresh will occur unless there's a connection failure. + # @option opts [Integer] :refresh_interval (90) If :refresh_mode is enabled, this is the number of seconds + # between calls to check the replica set's state. # @option opts [Boolean] :require_primary (true) If true, require a primary node for the connection - # to succeed. Otherwise, connection will succeed as long as there's at least one secondary. + # to succeed. Otherwise, connection will succeed as long as there's at least one secondary node. # # @example Connect to a replica set and provide two seed nodes. Note that the number of seed nodes does # not have to be equal to the number of replica set members. The purpose of seed nodes is to permit @@ -120,9 +120,14 @@ module Mongo @arbiters = [] # Refresh - @background_refresh = opts.fetch(:background_refresh, false) + @refresh_mode = opts.fetch(:refresh_mode, :sync) @refresh_interval = opts[:refresh_interval] || 90 + if ![:sync, :async, false].include?(@refresh_mode) + raise MongoArgumentError, + "Refresh mode must be one of :sync, :async, or false." + end + # Are we allowing reads from secondaries? if opts[:read_secondary] warn ":read_secondary options has now been deprecated and will " + @@ -165,14 +170,14 @@ module Mongo # Initiate a connection to the replica set. def connect - log(:debug, "Connecting...") + log(:info, "Connecting...") sync_synchronize(:EX) do return if @connected manager = PoolManager.new(self, @seeds) manager.connect update_config(manager) - initiate_background_refresh + initiate_refresh_mode if @require_primary && @primary.nil? #TODO: in v2.0, we'll let this be optional and do a lazy connect. raise ConnectionFailure, "Failed to connect to primary node." @@ -210,7 +215,7 @@ module Mongo return if sync_exclusive? sync_synchronize(:EX) do - log(:debug, "Refreshing...") + log(:info, "Refreshing...") @background_manager ||= PoolManager.new(self, @seeds) @background_manager.connect update_config(@background_manager) @@ -220,11 +225,12 @@ module Mongo end def connected? - @primary_pool || @read_pool + !@primary_pool.nil? || !@read_pool.nil? end # @deprecated def connecting? + warn "ReplSetConnection#connecting? is deprecated and will be removed in v2.0." false end @@ -333,8 +339,8 @@ module Mongo private - def initiate_background_refresh - if @background_refresh + def initiate_refresh_mode + if @refresh_mode == :async return if @refresh_thread && @refresh_thread.alive? @refresh_thread = Thread.new do while true do @@ -342,9 +348,9 @@ module Mongo refresh end end - else - @last_refresh = Time.now end + + @last_refresh = Time.now end # Checkout a socket for reading (i.e., a secondary node). @@ -444,8 +450,8 @@ module Mongo end # Refresh synchronously every @refresh_interval seconds - # if @background_refresh is false. - if !@background_refresh && + # if synchronous refresh mode is enabled. + if @refresh_mode == :sync && ((Time.now - @last_refresh) > @refresh_interval) refresh end diff --git a/lib/mongo/util/pool.rb b/lib/mongo/util/pool.rb index 2decf9d..fdaa1b1 100644 --- a/lib/mongo/util/pool.rb +++ b/lib/mongo/util/pool.rb @@ -69,7 +69,7 @@ module Mongo def inspect "#" + "@ping_time=#{@ping_time} #{@checked_out.size}/#{@size} sockets available.>" end def host_string