Added some read preference tests; refactoring; nice Pool#inspect.

lib/mongo/repl_set_connection.rb

@@ -349,11 +349,11 @@ module Mongo
     def checkout_tagged(tags)
       sync_synchronize(:SH) do
         tags.each do |k, v|
-          pools = @tags_to_pools[{k => v}]
-          if !pools.empty?
-            socket = pools.first.checkout
-            @sockets_to_pools[socket] = pools.first
-            socket
+          pool = @tags_to_pools[{k.to_s => v}]
+          if pool
+            socket = pool.checkout
+            @sockets_to_pools[socket] = pool
+            return socket
           end
         end
       end

lib/mongo/util/pool.rb

@@ -65,6 +65,11 @@ module Mongo
       @checked_out.clear
     end
 
+    def inspect
+      "#<Mongo::Pool:0x#{self.object_id.to_s(16)} @host=#{@host} @port=#{port} " +
+        "@ping_time=#{ping_time} #{@checked_out.size}/#{@size} sockets available.>"
+    end
+
     def host_string
       "#{@host}:#{@port}"
     end

lib/mongo/util/pool_manager.rb

@@ -84,16 +84,6 @@ module Mongo
       end
     end
 
-    # Sort each tag pool entry in descending order
-    # according to ping time.
-    def sort_tag_pools!
-      @tags_to_pools.each_value do |pool_list|
-        pool_list.sort! do |a, b|
-          a.ping_time <=> b.ping_time
-        end
-      end
-    end
-
     # Initialize the connection pools for the primary and secondary nodes.
     def initialize_pools(members)
       members.each do |member|
@@ -117,24 +107,43 @@ module Mongo
         end
       end
 
-      sort_tag_pools!
+
       @max_bson_size = members.first.config['maxBsonObjectSize'] ||
         Mongo::DEFAULT_MAX_BSON_SIZE
       @arbiters = members.first.arbiters
-      choose_read_pool
+
+      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|
+        if pool_list.length == 1
+          @tags_to_pools[k] = pool_list.first
+        else
+          @tags_to_pools[k] = nearby_pool_from_set(pool_list)
+        end
+      end
     end
 
     # Pick a node from the set of possible secondaries.
     # If more than one node is available, use the ping
     # time to figure out which nodes to choose from.
-    def choose_read_pool
+    def set_read_pool
       if @secondary_pools.empty?
          @read_pool = @primary_pool
       elsif @secondary_pools.size == 1
          @read_pool = @secondary_pools[0]
       else
+        @read_pool = nearby_pool_from_set(@secondary_pools)
+      end
+    end
+
+    def nearby_pool_from_set(pool_set)
       ping_ranges = Array.new(3) { |i| Array.new }
-        @secondary_pools.each do |pool|
+        pool_set.each do |pool|
           case pool.ping_time
             when 0..150
               ping_ranges[0] << pool
@@ -149,8 +158,7 @@ module Mongo
           break if !list.empty?
         end
 
-        @read_pool = list[rand(list.length)]
-      end
+      list[rand(list.length)]
     end
 
     # Iterate through the list of provided seed

test/replica_sets/query_secondaries.rb

@@ -7,7 +7,7 @@ class ReplicaSetQuerySecondariesTest < Test::Unit::TestCase
   include Mongo
 
   def setup
-    @conn = ReplSetConnection.new([RS.host, RS.ports[0]], :read_secondary => true)
+    @conn = ReplSetConnection.new([RS.host, RS.ports[0]], :read => :secondary)
     @db = @conn.db(MONGO_TEST_DB)
     @db.drop_collection("test-sets")
   end

test/replica_sets/read_preference_test.rb

@@ -0,0 +1,41 @@
+$:.unshift(File.join(File.dirname(__FILE__), '..', 'lib'))
+require './test/replica_sets/rs_test_helper'
+
+class ReadPreferenceTest < Test::Unit::TestCase
+  include Mongo
+
+  def setup
+    @conn = ReplSetConnection.new([RS.host, RS.ports[0], RS.host, RS.ports[1]], :read => :secondary, :pool_size => 50)
+    @db = @conn.db(MONGO_TEST_DB)
+    @db.drop_collection("test-sets")
+  end
+
+  def test_query_tagged
+    col = @db['mongo-test']
+
+    col.insert({:a => 1}, :safe => {:w => 3})
+    col.find_one({}, :read => {:db => "main"})
+    col.find_one({}, :read => {:dc => "ny"})
+    col.find_one({}, :read => {:dc => "sf"})
+
+    assert_raise Mongo::NodeWithTagsNotFound do
+      col.find_one({}, :read => {:foo => "bar"})
+    end
+
+    threads = []
+    100.times do
+      threads << Thread.new do
+        col.find_one({}, :read => {:dc => "sf"})
+      end
+    end
+
+    threads.each {|t| t.join }
+
+    col.remove
+  end
+
+  def teardown
+    RS.restart_killed_nodes
+  end
+
+end

test/tools/repl_set_manager.rb

@@ -43,13 +43,23 @@ class ReplSetManager
   end
 
   def start_set
-    puts "** Starting a replica set with #{@count} nodes"
+    begin
+    con = Mongo::Connection.new(@host, @start_port)
+      rescue Mongo::ConnectionFailure
+    end
 
+    if con && ensure_up(1, con)
+      should_start = false
+      puts "** Replica set already started."
+    else
+      should_start = true
       system("killall mongod")
+      puts "** Starting a replica set with #{@count} nodes"
+    end
 
     n = 0
     (@primary_count + @secondary_count).times do
-      init_node(n) do |attrs|
+      init_node(n, should_start) do |attrs|
         if @version[0] >= 2
           attrs['tags'] = @tags[n % @tags.size]
         end
@@ -58,22 +68,29 @@ class ReplSetManager
     end
 
     @passive_count.times do
-      init_node(n) do |attrs|
+      init_node(n, should_start) do |attrs|
         attrs['priority'] = 0
       end
       n += 1
     end
 
     @arbiter_count.times do
-      init_node(n) do |attrs|
+      init_node(n, should_start) do |attrs|
         attrs['arbiterOnly'] = true
       end
       n += 1
     end
 
+    if con && ensure_up(1, con)
+      @mongods.each do |k, v|
+        v['up'] = true
+        v['pid'] = File.open(File.join(v['db_path'], 'mongod.lock')).read.strip
+      end
+    else
       initiate
       ensure_up
     end
+  end
 
   def cleanup_set
     system("killall mongod")
@@ -82,18 +99,20 @@ class ReplSetManager
     end
   end
 
-  def init_node(n)
+  def init_node(n, should_start=true)
     @mongods[n] ||= {}
     port = @start_port + n
     @ports << port
     @mongods[n]['port'] = port
     @mongods[n]['db_path'] = get_path("rs-#{port}")
     @mongods[n]['log_path'] = get_path("log-#{port}")
+    @mongods[n]['start'] = start_cmd(n)
+
+    if should_start
       system("rm -rf #{@mongods[n]['db_path']}")
       system("mkdir -p #{@mongods[n]['db_path']}")
-
-    @mongods[n]['start'] = start_cmd(n)
       start(n)
+    end
 
     member = {'_id' => n, 'host' => "#{@host}:#{@mongods[n]['port']}"}
 
@@ -231,11 +250,11 @@ class ReplSetManager
   end
   alias :restart :start
 
-  def ensure_up
+  def ensure_up(n=nil, connection=nil)
     print "** Ensuring members are up..."
 
-    attempt do
-      con = get_connection
+    attempt(n) do
+      con = connection || get_connection
       status = con['admin'].command({'replSetGetStatus' => 1})
       print "."
       if status['members'].all? { |m| m['health'] == 1 &&
@@ -249,6 +268,8 @@ class ReplSetManager
         raise Mongo::OperationFailure
       end
     end
+
+    return false
   end
 
   def primary
@@ -336,11 +357,11 @@ class ReplSetManager
     File.join(@path, name)
   end
 
-  def attempt
+  def attempt(retries=nil)
     raise "No block given!" unless block_given?
     count = 0
 
-    while count < @retries do
+    while count < (retries || @retries) do
       begin
         return yield
         rescue Mongo::OperationFailure, Mongo::ConnectionFailure => ex