implement ConnectionLifeTime. fixes #212

Author: caleblloyd

src/MySqlConnector/MySqlClient/ConnectionPool.cs

@@ -53,11 +53,26 @@ public async Task<MySqlSession> GetSessionAsync(IOBehavior ioBehavior, Cancellat
 			}
 		}
 
+		private bool SessionIsHealthy(MySqlSession session)
+		{
+			if (!session.IsConnected)
+				return false;
+			if (session.PoolGeneration != m_generation)
+				return false;
+			if (session.DatabaseOverride != null)
+				return false;
+			if (m_connectionSettings.ConnectionLifeTime > 0
+			    && (DateTime.UtcNow - session.CreatedUtc).TotalSeconds >= m_connectionSettings.ConnectionLifeTime)
+				return false;
+
+			return true;
+		}
+
 		public void Return(MySqlSession session)
 		{
 			try
 			{
-				if (session.IsConnected && session.PoolGeneration == m_generation && session.DatabaseOverride == null)
+				if (SessionIsHealthy(session))
 					m_sessions.Enqueue(session);
 				else
 					session.DisposeAsync(IOBehavior.Synchronous, CancellationToken.None).ConfigureAwait(false);

src/MySqlConnector/Serialization/MySqlSession.cs

@@ -23,13 +23,15 @@ public MySqlSession()
 
 		public MySqlSession(ConnectionPool pool, int poolGeneration)
 		{
+			CreatedUtc = DateTime.UtcNow;
 			Pool = pool;
 			PoolGeneration = poolGeneration;
 		}
 
 		public ServerVersion ServerVersion { get; set; }
 		public int ConnectionId { get; set; }
 		public byte[] AuthPluginData { get; set; }
+		public DateTime CreatedUtc { get; }
 		public ConnectionPool Pool { get; }
 		public int PoolGeneration { get; }
 		public string DatabaseOverride { get; set; }

tests/SideBySide/ConnectionPool.cs

@@ -159,6 +159,35 @@ public async Task WaitTimeout()
 			}
 		}
 
+		[Theory]
+		[InlineData(2u, 3u, true)]
+		[InlineData(180u, 3u, false)]
+		public async Task ConnectionLifeTime(uint lifeTime, uint delaySeconds, bool shouldTimeout)
+		{
+			var csb = AppConfig.CreateConnectionStringBuilder();
+			csb.Pooling = true;
+			csb.MinimumPoolSize = 0;
+			csb.MaximumPoolSize = 1;
+			csb.ConnectionLifeTime = lifeTime;
+			int serverThread;
+
+			using (var connection = new MySqlConnection(csb.ConnectionString))
+			{
+				await connection.OpenAsync();
+				serverThread = connection.ServerThread;
+				await Task.Delay(TimeSpan.FromSeconds(delaySeconds));
+			}
+
+			using (var connection = new MySqlConnection(csb.ConnectionString))
+			{
+				await connection.OpenAsync();
+				if (shouldTimeout)
+					Assert.NotEqual(serverThread, connection.ServerThread);
+				else
+					Assert.Equal(serverThread, connection.ServerThread);
+			}
+		}
+
 		[Fact]
 		public async Task CharacterSet()
 		{

tests/SideBySide/SideBySide.csproj

@@ -15,8 +15,9 @@
     <PreserveCompilationContext>true</PreserveCompilationContext>
     <AssemblyName>SideBySide</AssemblyName>
     <PackageId>SideBySide</PackageId>
-    <GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>
     <ServerGarbageCollection>true</ServerGarbageCollection>
+    <ConcurrentGarbageCollection>true</ConcurrentGarbageCollection>
+    <ThreadPoolMinThreads>64</ThreadPoolMinThreads>
   </PropertyGroup>
 
  <ItemGroup>