Initialize MongoShardedClient with MONGODB_URI.

This fixes the errors that were occurring when instantiating a
MongoShardedClient when a MONGODB_URI environment variable is present.
This also fixes MongoShardedClient.from_uri to properly get a
MongoShardedClient connection from the URIParser.

[ RUBY-541 ]

Author: durran

lib/mongo/mongo_sharded_client.rb

@@ -16,11 +16,8 @@ def initialize(*args)
 
       if nodes.empty? and ENV.has_key?('MONGODB_URI')
         parser = URIParser.new ENV['MONGODB_URI']
-        if parser.direct?
-          raise MongoArgumentError, "Mongo::MongoShardedClient.new called with no arguments, but ENV['MONGODB_URI'] implies a direct connection."
-        end
         opts = parser.connection_options.merge! opts
-        nodes = [parser.nodes]
+        nodes = parser.node_strings
       end
 
       unless nodes.length > 0
@@ -61,7 +58,7 @@ def initialize(*args)
     end
 
     def valid_opts
-      GENERIC_OPTS + SHARDED_CLUSTER_OPTS
+      GENERIC_OPTS + SHARDED_CLUSTER_OPTS + READ_PREFERENCE_OPTS + WRITE_CONCERN_OPTS
     end
 
     def inspect
@@ -135,5 +132,17 @@ def checkout(&block)
         tries < 2 ? retry : raise
       end
     end
+
+    # Initialize a connection to MongoDB using the MongoDB URI spec.
+    #
+    # @param uri [ String ]  string of the format:
+    #   mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/database]
+    #
+    # @param opts [ Hash ] Any of the options available for MongoShardedClient.new
+    #
+    # @return [ Mongo::MongoShardedClient ] The sharded client.
+    def self.from_uri(uri = ENV['MONGODB_URI'], options = {})
+      URIParser.new(uri).connection(options, false, true)
+    end
   end
 end

lib/mongo/util/uri_parser.rb

@@ -140,16 +140,18 @@ def initialize(uri)
     # @note Don't confuse this with attribute getter method #connect.
     #
     # @return [MongoClient,MongoReplicaSetClient]
-    def connection(extra_opts, legacy=false)
-      opts = connection_options.merge! extra_opts
+    def connection(extra_opts, legacy = false, sharded = false)
+      opts = connection_options.merge!(extra_opts)
       if(legacy)
         if replicaset?
           ReplSetConnection.new(node_strings, opts)
         else
           Connection.new(host, port, opts)
         end
       else
-        if replicaset?
+        if sharded
+          MongoShardedClient.new(node_strings, opts)
+        elsif replicaset?
           MongoReplicaSetClient.new(node_strings, opts)
         else
           MongoClient.new(host, port, opts)

test/functional/uri_test.rb

@@ -174,4 +174,27 @@ def test_read_preference_when_no_replica_set
     parser = Mongo::URIParser.new("mongodb://localhost:27018?readPreference=nearest")
     assert_nil parser.connection_options[:read]
   end
+
+  def test_connection_when_sharded_with_no_options
+    parser = Mongo::URIParser.new("mongodb://localhost:27017,localhost:27018")
+    client = parser.connection({}, false, true)
+    assert_equal [[ "localhost", 27017 ], [ "localhost", 27018 ]], client.seeds
+    assert_true client.mongos?
+  end
+
+  def test_connection_when_sharded_with_options
+    parser = Mongo::URIParser.new("mongodb://localhost:27017,localhost:27018")
+    client = parser.connection({ :refresh_interval => 10 }, false, true)
+    assert_equal [[ "localhost", 27017 ], [ "localhost", 27018 ]], client.seeds
+    assert_equal 10, client.refresh_interval
+    assert_true client.mongos?
+  end
+
+  def test_connection_when_sharded_with_uri_options
+    parser = Mongo::URIParser.new("mongodb://localhost:27017,localhost:27018?readPreference=nearest")
+    client = parser.connection({}, false, true)
+    assert_equal [[ "localhost", 27017 ], [ "localhost", 27018 ]], client.seeds
+    assert_equal :nearest, client.read
+    assert_true client.mongos?
+  end
 end

test/unit/mongo_sharded_client_test.rb

@@ -0,0 +1,32 @@
+require "test_helper"
+
+class MongoShardedClientTest < Test::Unit::TestCase
+  include Mongo
+
+  def setup
+    ENV["MONGODB_URI"] = nil
+  end
+
+  def test_initialize_with_single_mongos_uri
+    ENV["MONGODB_URI"] = "mongodb://localhost:27017"
+    client = MongoShardedClient.new
+    assert_equal [[ "localhost", 27017 ]], client.seeds
+  end
+
+  def test_initialize_with_multiple_mongos_uris
+    ENV["MONGODB_URI"] = "mongodb://localhost:27017,localhost:27018"
+    client = MongoShardedClient.new
+    assert_equal [[ "localhost", 27017 ], [ "localhost", 27018 ]], client.seeds
+  end
+
+  def test_from_uri_with_string
+    client = MongoShardedClient.from_uri("mongodb://localhost:27017,localhost:27018")
+    assert_equal [[ "localhost", 27017 ], [ "localhost", 27018 ]], client.seeds
+  end
+
+  def test_from_uri_with_env_variable
+    ENV["MONGODB_URI"] = "mongodb://localhost:27017,localhost:27018"
+    client = MongoShardedClient.from_uri
+    assert_equal [[ "localhost", 27017 ], [ "localhost", 27018 ]], client.seeds
+  end
+end