Fix for connections to replica sets with 1 secondary and 1 arbiter

lib/mongo/connection.rb

@@ -629,9 +629,9 @@ module Mongo
 
     private
 
-    # Pick a node randomly from the set of possibly secondaries.
+    # Pick a node randomly from the set of possible secondaries.
     def pick_secondary_for_read
-      if (size = @secondary_pools.size) > 1
+      if (size = @secondary_pools.size) > 0
         @read_pool = @secondary_pools[rand(size)]
       end
     end
@@ -715,9 +715,7 @@ module Mongo
         if config['secondary']
           host, port = *node
           @secondaries << node unless @secondaries.include?(node)
-          if @read_secondary
           @secondary_pools << Pool.new(self, host, port, :size => @pool_size, :timeout => @timeout)
-          end
         elsif config['arbiterOnly']
           @arbiters << node unless @arbiters.include?(node)
         end

test/replica_sets/connect_test.rb

@@ -3,44 +3,45 @@ require 'mongo'
 require 'test/unit'
 require './test/test_helper'
 
-# NOTE: This test expects a replica set of three nodes to be running on local host.
+# NOTE: This test expects a replica set of three nodes to be running on TEST_HOST,
+# on ports TEST_PORT, TEST_PORT + 1, and TEST + 2.
 class ConnectTest < Test::Unit::TestCase
   include Mongo
 
   def test_connect_bad_name
     assert_raise_error(ReplicaSetConnectionError, "expected 'wrong-repl-set-name'") do
-      Mongo::Connection.multi([['localhost', 27017], ['localhost', 27018], ['localhost', 27019]],
+      Mongo::Connection.multi([[TEST_HOST, TEST_PORT], [TEST_HOST, TEST_PORT + 1], [TEST_HOST, TEST_PORT + 2]],
         :rs_name => "wrong-repl-set-name")
     end
   end
 
   def test_connect
-    @conn = Mongo::Connection.multi([['localhost', 27017], ['localhost', 27018], ['localhost', 27019]],
+    @conn = Mongo::Connection.multi([[TEST_HOST, TEST_PORT], [TEST_HOST, TEST_PORT + 1], [TEST_HOST, TEST_PORT + 2]],
                                     :name => "foo")
     assert @conn.connected?
   end
 
   def test_connect_with_first_node_down
-    puts "Please kill the node at 27017."
+    puts "Please kill the node at #{TEST_PORT}."
     gets
 
-    @conn = Mongo::Connection.multi([['localhost', 27017], ['localhost', 27018], ['localhost', 27019]])
+    @conn = Mongo::Connection.multi([[TEST_HOST, TEST_PORT], [TEST_HOST, TEST_PORT + 1], [TEST_HOST, TEST_PORT + 2]])
     assert @conn.connected?
   end
 
   def test_connect_with_second_node_down
-    puts "Please kill the node at 27018."
+    puts "Please kill the node at #{TEST_PORT + 1}."
     gets
 
-    @conn = Mongo::Connection.multi([['localhost', 27017], ['localhost', 27018], ['localhost', 27019]])
+    @conn = Mongo::Connection.multi([[TEST_HOST, TEST_PORT], [TEST_HOST, TEST_PORT + 1], [TEST_HOST, TEST_PORT + 2]])
     assert @conn.connected?
   end
 
   def test_connect_with_third_node_down
-    puts "Please kill the node at 27019."
+    puts "Please kill the node at #{TEST_PORT + 2}."
     gets
 
-    @conn = Mongo::Connection.multi([['localhost', 27017], ['localhost', 27018], ['localhost', 27019]])
+    @conn = Mongo::Connection.multi([[TEST_HOST, TEST_PORT], [TEST_HOST, TEST_PORT + 1], [TEST_HOST, TEST_PORT + 2]])
     assert @conn.connected?
   end
 end

test/test_helper.rb

@@ -25,13 +25,20 @@ unless defined? MONGO_TEST_DB
   MONGO_TEST_DB = 'ruby-test-' + BSON::ObjectId.new.to_s
 end
 
+unless defined? TEST_PORT
+  TEST_PORT = ENV['MONGO_RUBY_DRIVER_PORT'].to_i || Connection::DEFAULT_PORT
+end
+
+unless defined? TEST_HOST
+  TEST_HOST = ENV['MONGO_RUBY_DRIVER_HOST'] || 'localhost'
+end
+
 class Test::Unit::TestCase
   include Mongo
   include BSON
 
   def self.standard_connection(options={})
-    Connection.new(ENV['MONGO_RUBY_DRIVER_HOST'] || 'localhost',
+    Connection.new(TEST_HOST, TEST_PORT, options)
-      ENV['MONGO_RUBY_DRIVER_PORT'] || Connection::DEFAULT_PORT, options)
   end
 
   def standard_connection(options={})
@@ -43,11 +50,11 @@ class Test::Unit::TestCase
   end
 
   def self.mongo_host
-    ENV['MONGO_RUBY_DRIVER_HOST'] || 'localhost'
+    TEST_HOST
   end
 
   def self.mongo_port
-    ENV['MONGO_RUBY_DRIVER_PORT'] ? ENV['MONGO_RUBY_DRIVER_PORT'].to_i : 27017
+    TEST_PORT
   end
 
   def host_port