minor: simply and refactor auto refresh

lib/mongo/repl_set_connection.rb

@@ -23,7 +23,7 @@ module Mongo
   # Instantiates and manages connections to a MongoDB replica set.
   class ReplSetConnection < Connection
     attr_reader :secondaries, :arbiters, :secondary_pools,
-      :replica_set_name, :read_pool, :seeds, :tags_to_pools,
+      :replica_set_name, :read_pool, :seeds, :primary_tag_pool,
       :refresh_interval, :refresh_mode
 
     # Create a connection to a MongoDB replica set.
@@ -143,7 +143,7 @@ module Mongo
 
       # Maps
       @sockets_to_pools = {}
-      @tags_to_pools = {}
+      @primary_tag_pool = nil
 
       # Replica set name
       if opts[:rs_name]
@@ -186,35 +186,44 @@ module Mongo
       end
     end
 
-    # Note: this method must be called from within
-    # an exclusive lock.
-    def update_config(manager)
-      @arbiters = manager.arbiters.nil? ? [] : manager.arbiters.dup
-      @primary = manager.primary.nil? ? nil : manager.primary.dup
-      @secondaries = manager.secondaries.dup
-      @hosts = manager.hosts.dup
-
-      @primary_pool = manager.primary_pool
-      @read_pool    = manager.read_pool
-      @secondary_pools = manager.secondary_pools
-      @tags_to_pools   = manager.tags_to_pools
-      @seeds = manager.seeds
-      @manager = manager
-      @nodes = manager.nodes
-      @max_bson_size = manager.max_bson_size
+    # Refresh the current replica set configuration.
+    # This method will attempt to do a soft refresh,
+    # updating only those parts of the replica set that
+    # have changed. If that's not possible, the method
+    # will perform a hard refresh.
+    #
+    # @return [Boolean] +true+ if hard refresh
+    #   occurred. +false+ is returned when unable
+    #   to get the refresh lock.
+    def refresh(opts={})
+      if !connected?
+        @logger.warn("Not connected")
       end
 
-    # Refresh the current replica set configuration.
-    def refresh(opts={})
-      return false if !connected?
+      log(:info, "Checking replica set connection health...")
+      @manager.check_connection_health
 
-      # Return if another thread is already in the process of refreshing.
-      return if sync_exclusive?
+      if @manager.refresh_required?
+        hard_refresh!
+      end
 
-      sync_synchronize(:EX) do
-        log(:info, "Refreshing...")
+      return true
+    end
+
+    # Force a hard refresh of this connection's view
+    # of the replica set.
+    #
+    # @return [Boolean] +true+ if hard refresh
+    #   occurred. +false+ is returned when unable
+    #   to get the refresh lock.
+    def hard_refresh!
+      return false if sync_exclusive?
+
+      log(:info, "Initiating hard refresh...")
       @background_manager = PoolManager.new(self, @seeds)
       @background_manager.connect
+
+      sync_synchronize(:EX) do
         update_config(@background_manager)
       end
 
@@ -295,7 +304,7 @@ module Mongo
         @secondaries      = []
         @secondary_pools  = []
         @arbiters         = []
-        @tags_to_pools.clear
+        @primary_tag_pool = nil
         @sockets_to_pools.clear
       end
     end
@@ -336,6 +345,27 @@ module Mongo
 
     private
 
+    # Given a pool manager, update this connection's
+    # view of the replica set.
+    #
+    # This method must be called within
+    # an exclusive lock.
+    def update_config(manager)
+      @arbiters = manager.arbiters.nil? ? [] : manager.arbiters.dup
+      @primary = manager.primary.nil? ? nil : manager.primary.dup
+      @secondaries = manager.secondaries.dup
+      @hosts = manager.hosts.dup
+
+      @primary_pool = manager.primary_pool
+      @read_pool    = manager.read_pool
+      @secondary_pools = manager.secondary_pools
+      @primary_tag_pool = manager.primary_tag_pool
+      @seeds = manager.seeds
+      @manager = manager
+      @nodes = manager.nodes
+      @max_bson_size = manager.max_bson_size
+    end
+
     def initiate_refresh_mode
       if @refresh_mode == :async
         return if @refresh_thread && @refresh_thread.alive?
@@ -377,7 +407,7 @@ module Mongo
     def checkout_tagged(tags)
       sync_synchronize(:SH) do
         tags.each do |k, v|
-          pool = @tags_to_pools[{k.to_s => v}]
+          pool = @primary_tag_pool[{k.to_s => v}]
           if pool
             socket = pool.checkout
             @sockets_to_pools[socket] = pool

lib/mongo/util/node.rb

@@ -1,7 +1,8 @@
 module Mongo
   class Node
 
-    attr_accessor :host, :port, :address, :config, :connection, :socket
+    attr_accessor :host, :port, :address, :config, :connection, :socket,
+      :last_state
 
     def initialize(connection, data)
       @connection = connection

lib/mongo/util/pool.rb

@@ -19,10 +19,10 @@ module Mongo
   class Pool
     PING_ATTEMPTS = 6
 
-    attr_accessor :host, :port, :size, :timeout, :safe, :checked_out, :connection
+    attr_accessor :host, :port, :address,
+      :size, :timeout, :safe, :checked_out, :connection
 
     # Create a new pool of connections.
-    #
     def initialize(connection, host, port, opts={})
       @connection  = connection
 
@@ -31,6 +31,9 @@ module Mongo
       # A Mongo::Node object.
       @node = opts[:node]
 
+      # The string address
+      @address = "#{@host}:#{@port}"
+
       # Pool size and timeout.
       @size      = opts[:size] || 1
       @timeout   = opts[:timeout]   || 5.0

lib/mongo/util/pool_manager.rb

@@ -3,7 +3,7 @@ module Mongo
 
     attr_reader :connection, :seeds, :arbiters, :primary, :secondaries,
       :primary_pool, :read_pool, :secondary_pools, :hosts, :nodes, :max_bson_size,
-      :tags_to_pools, :members
+      :tags_to_pools, :primary_tag_pool, :members
 
     def initialize(connection, seeds)
       @connection = connection
@@ -24,13 +24,50 @@ module Mongo
       members = connect_to_members
       initialize_pools(members)
       update_seed_list(members)
+      set_read_pool
+      set_primary_tag_pools
 
       @members = members
       @previously_connected = true
     end
 
-    def healthy?
+    # We're healthy if all members are pingable and if the view
+    # of the replica set returned by isMaster is equivalent
+    # to our view. If any of these isn't the case,
+    # set @refresh_require to true, and return.
+    def check_connection_health
+      @refresh_required = false
 
+      begin
+        seed = get_valid_seed_node
+      rescue ConnectionFailure
+        @refresh_required = true
+        return
+      end
+
+      config = seed.set_config
+      if !config
+        @refresh_required = true
+        return
+      end
+
+      config['hosts'].each do |host|
+        member = @members.detect do |m|
+          m.address == host
+        end
+
+        if member && validate_existing_member(member)
+          next
+        else
+          @refresh_required = true
+          return false
+        end
+      end
+    end
+
+    # The replica set connection should initiate a full refresh.
+    def refresh_required?
+      @refresh_required
     end
 
     def close
@@ -57,6 +94,24 @@ module Mongo
 
     private
 
+    def validate_existing_member(member)
+      config = member.set_config
+      if !config
+        return false
+      else
+        if member.primary?
+          if member.last_state == :primary
+            return true
+          else # This node is now primary, but didn't used to be.
+            return false
+          end
+        elsif member.last_state == :secondary &&
+          member.secondary?
+          return true
+        end
+      end
+    end
+
     def initialize_data
       @primary = nil
       @primary_pool = nil
@@ -67,6 +122,7 @@ module Mongo
       @hosts = Set.new
       @members = Set.new
       @tags_to_pools = {}
+      @primary_tag_pool = {}
     end
 
     # Connect to each member of the replica set
@@ -105,13 +161,29 @@ module Mongo
         @hosts << member.host_string
 
         if member.primary?
+          assign_primary(member)
+        elsif member.secondary? && !@secondaries.include?(member.host_port)
+          assign_secondary(member)
+        end
+      end
+
+      @max_bson_size = members.first.config['maxBsonObjectSize'] ||
+        Mongo::DEFAULT_MAX_BSON_SIZE
+      @arbiters = members.first.arbiters
+    end
+
+    def assign_primary(member)
+      member.last_state = :primary
       @primary = member.host_port
       @primary_pool = Pool.new(self.connection, member.host, member.port,
                               :size => self.connection.pool_size,
                               :timeout => self.connection.connect_timeout,
                               :node => member)
       associate_tags_with_pool(member.tags, @primary_pool)
-        elsif member.secondary? && !@secondaries.include?(member.host_port)
+    end
+
+    def assign_secondary(member)
+      member.last_state = :secondary
       @secondaries << member.host_port
       pool = Pool.new(self.connection, member.host, member.port,
                                    :size => self.connection.pool_size,
@@ -120,25 +192,15 @@ module Mongo
       @secondary_pools << pool
       associate_tags_with_pool(member.tags, pool)
     end
-      end
-
-
-      @max_bson_size = members.first.config['maxBsonObjectSize'] ||
-        Mongo::DEFAULT_MAX_BSON_SIZE
-      @arbiters = members.first.arbiters
-
-      set_read_pool
-      set_primary_tag_pools
-    end
 
     # If there's more than one pool associated with
     # a given tag, choose a close one using the bucket method.
     def set_primary_tag_pools
-      @tags_to_pools.each do |k, pool_list|
+      @tags_to_pools.each do |key, pool_list|
         if pool_list.length == 1
-          @tags_to_pools[k] = pool_list.first
+          @primary_tag_pool[key] = pool_list.first
         else
-          @tags_to_pools[k] = nearby_pool_from_set(pool_list)
+          @primary_tag_pool[key] = nearby_pool_from_set(pool_list)
         end
       end
     end

test/replica_sets/read_preference_test.rb

@@ -1,18 +1,20 @@
 $:.unshift(File.join(File.dirname(__FILE__), '..', 'lib'))
 require './test/replica_sets/rs_test_helper'
+require 'logger'
 
 # TODO: enable this once we enable reads from tags.
 class ReadPreferenceTest < Test::Unit::TestCase
   include Mongo
 
   def test_long_write_with_async_refresh
+    log = Logger.new("test.log")
     conn = ReplSetConnection.new([RS.host, RS.ports[0], RS.host, RS.ports[1]],
           :read => :secondary, :pool_size => 50,
-          :refresh_mode => :async, :refresh_interval => 5)
+          :refresh_mode => :sync, :refresh_interval => 5, :logger => log)
 
     db = conn.db(MONGO_TEST_DB)
     db.drop_collection("test-sets")
-    col = @db['mongo-test']
+    col = db['mongo-test']
 
     100000.times do |n|
       col.insert({:n => n, :str => "0000000000"})