NH-3724 - Added support for notification handlers

src/NHibernate.Test/CfgTest/Loquacious/ConfigurationFixture.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Data;
 using System.Data.SqlClient;
 using System.IO;
@@ -11,12 +12,26 @@
 using NHibernate.Hql.Ast.ANTLR;
 using NHibernate.Type;
 using NUnit.Framework;
+using Environment = NHibernate.Cfg.Environment;
 
 namespace NHibernate.Test.CfgTest.Loquacious
 {
 	[TestFixture]
 	public class ConfigurationFixture
 	{
+		[Test]
+		public void CanSetNotificationHandler()
+		{
+			//NH-3724
+			EventHandler<SqlInfoMessageEventArgs> handler = (s, e) => {};
+			var cfg = new Configuration().DataBaseIntegration(x =>
+			{
+				x.WithNotificationHandler(handler);
+			}).Configure();
+
+			Assert.IsNotNull(cfg.NotificationHandler);
+		}
+
 		[Test]
 		public void CompleteConfiguration()
 		{

src/NHibernate.Test/NHSpecificTest/GH1547/Fixture.cs

@@ -179,6 +179,11 @@ void IDriver.Configure(IDictionary<string, string> settings)
 			_driverImplementation.Configure(settings);
 		}
 
+		public void AddNotificationHandler(DbConnection con, Delegate handler)
+		{
+			_driverImplementation.AddNotificationHandler(con, handler);
+		}
+
 		DbConnection IDriver.CreateConnection()
 		{
 			return _driverImplementation.CreateConnection();

src/NHibernate.Test/TypesTest/AbstractDateTimeTypeFixture.cs

@@ -630,6 +630,11 @@ void IDriver.Configure(IDictionary<string, string> settings)
 			_driverImplementation.Configure(settings);
 		}
 
+		public void AddNotificationHandler(DbConnection con, Delegate handler)
+		{
+			_driverImplementation.AddNotificationHandler(con, handler);
+		}
+
 		DbConnection IDriver.CreateConnection()
 		{
 			return _driverImplementation.CreateConnection();

src/NHibernate/AdoNet/ConnectionManager.cs

@@ -240,6 +240,11 @@ public DbConnection GetConnection()
 				if (_ownConnection)
 				{
 					_connection = Factory.ConnectionProvider.GetConnection();
+					//NH-3724
+					if (Factory.Settings.NotificationHandler != null)
+					{
+						Factory.ConnectionProvider.Driver.AddNotificationHandler(_connection, Factory.Settings.NotificationHandler);
+					}
 					// Will fail if the connection is already enlisted in another transaction.
 					// Probable case: nested transaction scope with connection auto-enlistment enabled.
 					// That is an user error.

src/NHibernate/Async/AdoNet/ConnectionManager.cs

@@ -62,6 +62,11 @@ async Task<DbConnection> InternalGetConnectionAsync()
 					if (_ownConnection)
 					{
 						_connection = await (Factory.ConnectionProvider.GetConnectionAsync(cancellationToken)).ConfigureAwait(false);
+						//NH-3724
+						if (Factory.Settings.NotificationHandler != null)
+						{
+							Factory.ConnectionProvider.Driver.AddNotificationHandler(_connection, Factory.Settings.NotificationHandler);
+						}
 						// Will fail if the connection is already enlisted in another transaction.
 						// Probable case: nested transaction scope with connection auto-enlistment enabled.
 						// That is an user error.

src/NHibernate/Cfg/Configuration.cs

@@ -183,6 +183,7 @@ protected void Reset()
 			tableNameBinding = new Dictionary<string, Mappings.TableDescription>();
 			columnNameBindingPerTable = new Dictionary<Table, Mappings.ColumnNames>();
 			filtersSecondPasses = new Queue<FilterSecondPassArgs>();
+			NotificationHandler = null;
 		}
 
 		[Serializable]
@@ -1405,6 +1406,14 @@ public Configuration SetDefaultNamespace(string newDefaultNamespace)
 			return this;
 		}
 
+		//NH-3724
+
+		public Delegate NotificationHandler
+		{
+			get => _notificationHandler;
+			set => _notificationHandler = value;
+		}
+
 		/// <summary>
 		/// Sets the default interceptor for use by all sessions.
 		/// </summary>
@@ -1763,6 +1772,8 @@ private Settings BuildSettings()
 			// NH : Set configuration for IdGenerator SQL logging
 			PersistentIdGeneratorParmsNames.SqlStatementLogger.FormatSql = result.SqlStatementLogger.FormatSql;
 			PersistentIdGeneratorParmsNames.SqlStatementLogger.LogToStdout = result.SqlStatementLogger.LogToStdout;
+			//NH-3724
+			result.NotificationHandler = NotificationHandler;
 			return result;
 		}
 
@@ -1928,6 +1939,9 @@ protected virtual string GetDefaultConfigurationFilePath()
 		#endregion
 
 		private XmlSchemas schemas;
+
+		[NonSerialized]
+		private Delegate _notificationHandler;
 
 		private XmlSchemas Schemas
 		{

src/NHibernate/Cfg/Loquacious/DbIntegrationConfigurationProperties.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Data;
 using NHibernate.AdoNet;
 using NHibernate.Connection;
@@ -19,6 +20,12 @@ public DbIntegrationConfigurationProperties(Configuration configuration)
 
 		#region Implementation of IDbIntegrationConfigurationProperties
 
+		public void WithNotificationHandler(Delegate handler)
+		{
+			//NH-3724
+			configuration.NotificationHandler = handler;
+		}
+
 		public void Dialect<TDialect>() where TDialect : Dialect.Dialect
 		{
 			configuration.SetProperty(Environment.Dialect, typeof(TDialect).AssemblyQualifiedName);

src/NHibernate/Cfg/Loquacious/IDbIntegrationConfigurationProperties.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Data;
 using NHibernate.AdoNet;
 using NHibernate.Connection;
@@ -15,6 +16,9 @@ public interface IDbIntegrationConfigurationProperties
 		bool LogSqlInConsole { set; }
 		bool LogFormattedSql { set; }
 
+		//NH-3724
+		void WithNotificationHandler(Delegate handler);
+
 		void ConnectionProvider<TProvider>() where TProvider : IConnectionProvider;
 		void Driver<TDriver>() where TDriver : IDriver;
 		IsolationLevel IsolationLevel { set; }

src/NHibernate/Cfg/Settings.cs

@@ -31,6 +31,9 @@ public Settings()
 		//private int jdbcFetchSize;
 
 		#endregion
+
+		public Delegate NotificationHandler { get; internal set; }
+
 		public SqlStatementLogger SqlStatementLogger { get; internal set; }
 
 		public int MaximumFetchDepth { get; internal set; }

src/NHibernate/Driver/DriverBase.cs

@@ -21,6 +21,22 @@ public abstract class DriverBase : IDriver, ISqlParameterFormatter
 		private int commandTimeout;
 		private bool prepareSql;
 
+		public virtual void AddNotificationHandler(DbConnection con, Delegate handler)
+		{
+			//NH-3724
+			if (handler != null)
+			{
+				var prop = con.GetType().GetEvent("InfoMessage");
+
+				if (prop == null)
+				{
+					throw new NotSupportedException("Current driver does not support notifications.");
+				}
+
+				prop.AddEventHandler(con, handler);
+			}
+		}
+
 		public virtual void Configure(IDictionary<string, string> settings)
 		{
 			// Command timeout

src/NHibernate/Driver/IDriver.cs

@@ -37,6 +37,14 @@ public interface IDriver
 		/// </summary>
 		void Configure(IDictionary<string, string> settings);
 
+		//NH-3724
+		/// <summary>
+		/// Attaches an event handler for the notification event (InfoMessage in most ADO.NET drivers).
+		/// </summary>
+		/// <param name="con"></param>
+		/// <param name="handler"></param>
+		void AddNotificationHandler(DbConnection con, Delegate handler);
+
 		/// <summary>
 		/// Creates an uninitialized DbConnection object for the specific Driver
 		/// </summary>

src/NHibernate/Driver/IfxDriver.cs

@@ -1,3 +1,6 @@
+using System;
+using System.Data;
+
 namespace NHibernate.Driver
 {
 	/// <summary>

src/NHibernate/Driver/NpgsqlDriver.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Data;
 using System.Data.Common;
 using NHibernate.AdoNet;
@@ -41,6 +42,12 @@ public NpgsqlDriver() : base(
 		{
 		}
 
+		public override void AddNotificationHandler(DbConnection con, Delegate handler)
+		{
+			//NH-3724
+			con.GetType().GetEvent("Notification").AddEventHandler(con, handler);
+		}
+
 		public override bool UseNamedPrefixInSql => true;
 
 		public override bool UseNamedPrefixInParameter => true;

src/NHibernate/Driver/OdbcDriver.cs

@@ -38,6 +38,7 @@ public override void Configure(IDictionary<string, string> settings)
 			}
 		}
 
+
 #if !NETFX
 		public OdbcDriver() 
 			: base("System.Data.Odbc", "System.Data.Odbc.OdbcConnection", "System.Data.Odbc.OdbcCommand")
@@ -49,6 +50,12 @@ public override DbConnection CreateConnection()
 			return new System.Data.Odbc.OdbcConnection();
 		}
 
+		public override void AddNotificationHandler(DbConnection con, Delegate handler)
+		{
+			//NH-3724
+			(con as System.Data.Odbc.OdbcConnection).InfoMessage += (System.Data.Odbc.OdbcInfoMessageEventHandler) handler;
+		}
+
 		public override DbCommand CreateCommand()
 		{
 			return new System.Data.Odbc.OdbcCommand();

src/NHibernate/Driver/OleDbDriver.cs

@@ -28,6 +28,12 @@ public override DbConnection CreateConnection()
 			return new System.Data.OleDb.OleDbConnection();
 		}
 
+		public override void AddNotificationHandler(DbConnection con, Delegate handler)
+		{
+			//NH-3724
+			(con as System.Data.OleDb.OleDbConnection).InfoMessage += (System.Data.OleDb.OleDbInfoMessageEventHandler) handler;
+		}
+
 		public override DbCommand CreateCommand()
 		{
 			return new System.Data.OleDb.OleDbCommand();

src/NHibernate/Driver/SqlClientDriver.cs

@@ -9,7 +9,6 @@
 using NHibernate.Dialect;
 using NHibernate.Engine;
 using NHibernate.SqlTypes;
-using NHibernate.Type;
 
 namespace NHibernate.Driver
 {
@@ -88,6 +87,12 @@ public override DbConnection CreateConnection()
 			return new SqlConnection();
 		}
 
+		public override void AddNotificationHandler(DbConnection con, Delegate handler)
+		{
+			//NH-3724
+			(con as SqlConnection).InfoMessage += (SqlInfoMessageEventHandler) handler;
+		}
+
 		/// <summary>
 		/// Creates an uninitialized <see cref="DbCommand" /> object for
 		/// the SqlClientDriver.