CSHARP574: added secondary acceptable latency to connection strings and urls to support changin the default value.

Author: craiggwilson

Driver/Core/MongoConnectionStringBuilder.cs

@@ -55,6 +55,8 @@ public class MongoConnectionStringBuilder : DbConnectionStringBuilder
             { "readpreferencetags", "readPreferenceTags" },
             { "replicaset", "replicaSet" },
             { "safe", "safe" },
+            { "secondaryacceptablelatency", "secondaryAcceptableLatency" },
+            { "secondaryacceptablelatencyms", "secondaryAcceptableLatency" },
             { "server", "server" },
             { "servers", "server" },
             { "slaveok", "slaveOk" },
@@ -88,6 +90,7 @@ public class MongoConnectionStringBuilder : DbConnectionStringBuilder
         private ReadPreference _readPreference;
         private string _replicaSetName;
         private SafeMode _safeMode;
+        private TimeSpan _secondaryAcceptableLatency;
         private IEnumerable<MongoServerAddress> _servers;
         private bool? _slaveOk;
         private TimeSpan _socketTimeout;
@@ -362,6 +365,20 @@ public SafeMode SafeMode
             }
         }
 
+        /// <summary>
+        /// Gets or sets the acceptable latency for considering a replica set member for inclusion in load balancing
+        /// when using a read preference of Secondary, SecondaryPreferred, and Nearest.
+        /// </summary>
+        public TimeSpan SecondaryAcceptableLatency
+        {
+            get { return _secondaryAcceptableLatency; }
+            set
+            {
+                _secondaryAcceptableLatency = value;
+                base["SecondaryAcceptableLatency"] = MongoUrlBuilder.FormatTimeSpan(value);
+            }
+        }
+
         /// <summary>
         /// Gets or sets the address of the server (see also Servers if using more than one address).
         /// </summary>
@@ -617,6 +634,10 @@ public override object this[string keyword]
                         newSafeMode.Enabled = Convert.ToBoolean(value);
                         SafeMode = newSafeMode;
                         break;
+                    case "secondaryacceptablelatency":
+                    case "secondaryacceptablelatencyms":
+                        SecondaryAcceptableLatency = ToTimeSpan(keyword, value);
+                        break;
                     case "server":
                     case "servers":
                         Servers = ParseServersString((string)value);
@@ -704,7 +725,8 @@ public MongoServerSettings ToServerSettings()
             var readPreference = ReadPreference ?? ReadPreference.Primary;
             return new MongoServerSettings(_connectionMode, _connectTimeout, null, defaultCredentials, _guidRepresentation, _ipv6,
                 _maxConnectionIdleTime, _maxConnectionLifeTime, _maxConnectionPoolSize, _minConnectionPoolSize, readPreference, _replicaSetName,
-                _safeMode ?? MongoDefaults.SafeMode, _servers, _socketTimeout, _useSsl, _verifySslCertificate, ComputedWaitQueueSize, _waitQueueTimeout);
+                _safeMode ?? MongoDefaults.SafeMode, _secondaryAcceptableLatency, _servers, _socketTimeout, _useSsl, _verifySslCertificate, 
+                ComputedWaitQueueSize, _waitQueueTimeout);
         }
 
         // private methods
@@ -773,6 +795,7 @@ private void ResetValues()
             _readPreference = null;
             _replicaSetName = null;
             _safeMode = null;
+            _secondaryAcceptableLatency = MongoDefaults.SecondaryAcceptableLatency;
             _servers = null;
             _slaveOk = null;
             _socketTimeout = MongoDefaults.SocketTimeout;

Driver/Core/MongoServerSettings.cs

@@ -44,6 +44,7 @@ public class MongoServerSettings
         private ReadPreference _readPreference;
         private string _replicaSetName;
         private SafeMode _safeMode;
+        private TimeSpan _secondaryAcceptableLatency;
         private List<MongoServerAddress> _servers;
         private ReadOnlyCollection<MongoServerAddress> _serversReadOnly;
         private TimeSpan _socketTimeout;
@@ -76,6 +77,7 @@ public MongoServerSettings()
             _readPreference = ReadPreference.Primary;
             _replicaSetName = null;
             _safeMode = MongoDefaults.SafeMode;
+            _secondaryAcceptableLatency = TimeSpan.FromMilliseconds(15);
             _servers = new List<MongoServerAddress> { new MongoServerAddress("localhost") };
             _serversReadOnly = new ReadOnlyCollection<MongoServerAddress>(_servers);
             _socketTimeout = MongoDefaults.SocketTimeout;
@@ -121,6 +123,7 @@ public MongoServerSettings(
             ReadPreference readPreference,
             string replicaSetName,
             SafeMode safeMode,
+            TimeSpan secondaryAcceptableLatency,
             IEnumerable<MongoServerAddress> servers,
             TimeSpan socketTimeout,
             bool useSsl,
@@ -154,6 +157,7 @@ public MongoServerSettings(
             _readPreference = readPreference;
             _replicaSetName = replicaSetName;
             _safeMode = safeMode;
+            _secondaryAcceptableLatency = secondaryAcceptableLatency;
             _servers = new List<MongoServerAddress>(servers);
             _serversReadOnly = new ReadOnlyCollection<MongoServerAddress>(_servers);
             _socketTimeout = socketTimeout;
@@ -361,6 +365,20 @@ public SafeMode SafeMode
             }
         }
 
+        /// <summary>
+        /// Gets or sets the acceptable latency for considering a replica set member for inclusion in load balancing
+        /// when using a read preference of Secondary, SecondaryPreferred, and Nearest.
+        /// </summary>
+        public TimeSpan SecondaryAcceptableLatency
+        {
+            get { return _secondaryAcceptableLatency; }
+            set
+            {
+                if (_isFrozen) { throw new InvalidOperationException("MongoServerSettings is frozen."); }
+                _secondaryAcceptableLatency = value;
+            }
+        }
+
         /// <summary>
         /// Gets or sets the address of the server (see also Servers if using more than one address).
         /// </summary>
@@ -488,8 +506,8 @@ public MongoServerSettings Clone()
         {
             return new MongoServerSettings(_connectionMode, _connectTimeout, _credentialsStore.Clone(), _defaultCredentials,
                 _guidRepresentation, _ipv6, _maxConnectionIdleTime, _maxConnectionLifeTime, _maxConnectionPoolSize,
-                _minConnectionPoolSize, _readPreference, _replicaSetName, _safeMode, _servers, _socketTimeout, _useSsl, _verifySslCertificate,
-                _waitQueueSize, _waitQueueTimeout);
+                _minConnectionPoolSize, _readPreference, _replicaSetName, _safeMode, _secondaryAcceptableLatency, _servers, 
+                _socketTimeout, _useSsl, _verifySslCertificate, _waitQueueSize, _waitQueueTimeout);
         }
 
         /// <summary>
@@ -526,6 +544,7 @@ public override bool Equals(object obj)
                         _readPreference == rhs._readPreference &&
                         _replicaSetName == rhs._replicaSetName &&
                         _safeMode == rhs._safeMode &&
+                        _secondaryAcceptableLatency == rhs._secondaryAcceptableLatency &&
                         _servers.SequenceEqual(rhs._servers) &&
                         _socketTimeout == rhs._socketTimeout &&
                         _useSsl == rhs._useSsl &&
@@ -626,6 +645,7 @@ public override int GetHashCode()
             hash = 37 * hash + _readPreference.GetHashCode();
             hash = 37 * hash + ((_replicaSetName == null) ? 0 : _replicaSetName.GetHashCode());
             hash = 37 * hash +  _safeMode.GetHashCode();
+            hash = 37 * hash + _secondaryAcceptableLatency.GetHashCode();
             foreach (var server in _servers)
             {
                 hash = 37 * hash + server.GetHashCode();
@@ -663,6 +683,7 @@ public override string ToString()
             sb.AppendFormat("ReadPreference={0};", _readPreference);
             sb.AppendFormat("ReplicaSetName={0};", _replicaSetName);
             sb.AppendFormat("SafeMode={0};", _safeMode);
+            sb.AppendFormat("SecondaryAcceptableLatency={0};", _secondaryAcceptableLatency);
             sb.AppendFormat("Servers={0};", string.Join(",", _servers.Select(s => s.ToString()).ToArray()));
             sb.AppendFormat("SocketTimeout={0};", _socketTimeout);
             sb.AppendFormat("Ssl={0};", _useSsl);

Driver/Core/MongoUrlBuilder.cs

@@ -47,6 +47,7 @@ public class MongoUrlBuilder
         private ReadPreference _readPreference;
         private string _replicaSetName;
         private SafeMode _safeMode;
+        private TimeSpan _secondaryAcceptableLatency;
         private IEnumerable<MongoServerAddress> _servers;
         private bool? _slaveOk;
         private TimeSpan _socketTimeout;
@@ -231,6 +232,16 @@ public SafeMode SafeMode
             set { _safeMode = value; }
         }
 
+        /// <summary>
+        /// Gets or sets the acceptable latency for considering a replica set member for inclusion in load balancing
+        /// when using a read preference of Secondary, SecondaryPreferred, and Nearest.
+        /// </summary>
+        public TimeSpan SecondaryAcceptableLatency
+        {
+            get { return _secondaryAcceptableLatency; }
+            set { _secondaryAcceptableLatency = value; }
+        }
+
         /// <summary>
         /// Gets or sets the address of the server (see also Servers if using more than one address).
         /// </summary>
@@ -637,6 +648,10 @@ public void Parse(string url)
                                 if (_safeMode == null) { _safeMode = new SafeMode(false); }
                                 SafeMode.Enabled = ParseBoolean(name, value);
                                 break;
+                            case "secondaryacceptablelatency":
+                            case "secondaryacceptablelatencyms":
+                                _secondaryAcceptableLatency = ParseTimeSpan(name, value);
+                                break;
                             case "slaveok":
                                 _slaveOk = ParseBoolean(name, value);
                                 break;
@@ -706,7 +721,8 @@ public MongoServerSettings ToServerSettings()
             var readPreference = ReadPreference ?? ReadPreference.Primary;
             return new MongoServerSettings(_connectionMode, _connectTimeout, null, _defaultCredentials, _guidRepresentation, _ipv6,
                 _maxConnectionIdleTime, _maxConnectionLifeTime, _maxConnectionPoolSize, _minConnectionPoolSize, readPreference, _replicaSetName,
-                _safeMode ?? MongoDefaults.SafeMode, _servers, _socketTimeout, _useSsl, _verifySslCertificate, ComputedWaitQueueSize, _waitQueueTimeout);
+                _safeMode ?? MongoDefaults.SafeMode, _secondaryAcceptableLatency, _servers, _socketTimeout, _useSsl, _verifySslCertificate, 
+                ComputedWaitQueueSize, _waitQueueTimeout);
         }
 
         /// <summary>
@@ -827,6 +843,10 @@ public override string ToString()
             {
                 query.AppendFormat("minPoolSize={0};", _minConnectionPoolSize);
             }
+            if (_secondaryAcceptableLatency != MongoDefaults.SecondaryAcceptableLatency)
+            {
+                query.AppendFormat("secondaryAcceptableLatency={0};", FormatTimeSpan(_secondaryAcceptableLatency));
+            }
             if (_socketTimeout != MongoDefaults.SocketTimeout)
             {
                 query.AppendFormat("socketTimeout={0};", FormatTimeSpan(_socketTimeout));
@@ -876,6 +896,7 @@ private void ResetValues()
             _readPreference = null;
             _replicaSetName = null;
             _safeMode = null;
+            _secondaryAcceptableLatency = MongoDefaults.SecondaryAcceptableLatency;
             _servers = null;
             _slaveOk = null;
             _socketTimeout = MongoDefaults.SocketTimeout;

Driver/Internal/MultipleInstanceMongoServerProxy.cs

@@ -139,6 +139,15 @@ public MongoServerState State
             }
         }
 
+        //protected properties
+        /// <summary>
+        /// Gets the server.
+        /// </summary>
+        protected MongoServer Server
+        {
+            get { return _server; }
+        }
+
         // public methods
         /// <summary>
         /// Chooses the server instance.

Driver/Internal/ReplicaSetMongoServerProxy.cs

@@ -72,7 +72,7 @@ public string ReplicaSetName
         // protected methods
         protected override MongoServerInstance ChooseServerInstance(ConnectedInstanceCollection connectedInstances, ReadPreference readPreference)
         {
-            var secondaryAcceptableLatency = TimeSpan.FromMilliseconds(15); // TODO: make configurable
+            var secondaryAcceptableLatency = Server.Settings.SecondaryAcceptableLatency;
 
             switch (readPreference.ReadPreferenceMode)
             {
@@ -207,7 +207,7 @@ protected override void ProcessConnectedInstanceStateChange(MongoServerInstance
         /// <param name="readPreference">The read preference that must be matched.</param>
         /// <param name="secondaryAcceptableLatency">The maximum acceptable secondary latency.</param>
         /// <returns>A randomly selected matching instance.</returns>
-        public MongoServerInstance GetMatchingInstance(List<ConnectedInstanceCollection.InstanceWithPingTime> instancesWithPingTime, ReadPreference readPreference, TimeSpan secondaryAcceptableLatency)
+        private MongoServerInstance GetMatchingInstance(List<ConnectedInstanceCollection.InstanceWithPingTime> instancesWithPingTime, ReadPreference readPreference, TimeSpan secondaryAcceptableLatency)
         {
             var tagSets = readPreference.TagSets ?? new ReplicaSetTagSet[] { new ReplicaSetTagSet() };
             foreach (var tagSet in tagSets)

Driver/Internal/ShardedMongoServerProxy.cs

@@ -66,7 +66,7 @@ protected override MongoServerInstance ChooseServerInstance(ConnectedInstanceCol
             }
             else
             {
-                var secondaryAcceptableLatency = TimeSpan.FromMilliseconds(15); // TODO: make configurable
+                var secondaryAcceptableLatency = Server.Settings.SecondaryAcceptableLatency;
                 var minPingTime = instancesWithPingTime[0].CachedAveragePingTime;
                 var maxPingTime = minPingTime + secondaryAcceptableLatency;
                 var n = instancesWithPingTime.Count(i => i.CachedAveragePingTime <= maxPingTime);

Driver/MongoDefaults.cs

@@ -37,6 +37,7 @@ public static class MongoDefaults
         private static int __maxMessageLength = 16000000; // 16MB (not 16 MiB!)
         private static int __minConnectionPoolSize = 0;
         private static SafeMode __safeMode = SafeMode.False;
+        private static TimeSpan __secondaryAcceptableLatency = TimeSpan.FromMilliseconds(15);
         private static TimeSpan __socketTimeout = TimeSpan.Zero; // use operating system default (presumably infinite)
         private static int __tcpReceiveBufferSize = 64 * 1024; // 64KiB (note: larger than 2MiB fails on Mac using Mono)
         private static int __tcpSendBufferSize = 64 * 1024; // 64KiB (TODO: what is the optimum value for the buffers?)
@@ -153,6 +154,16 @@ public static SafeMode SafeMode
             set { __safeMode = value; }
         }
 
+        /// <summary>
+        /// Gets or sets the default acceptable latency for considering a replica set member for inclusion in load balancing
+        /// when using a read preference of Secondary, SecondaryPreferred, and Nearest.
+        /// </summary>
+        public static TimeSpan SecondaryAcceptableLatency
+        {
+            get { return __secondaryAcceptableLatency; }
+            set { __secondaryAcceptableLatency = value; }
+        }
+
         /// <summary>
         /// Gets or sets the socket timeout.
         /// </summary>