support keep alives

src/EventStore.Client/ChannelFactory.cs

@@ -1,11 +1,15 @@
 using System;
 using System.Net;
 using Grpc.Core;
+
 #if !GRPC_CORE
 using System.Net.Http;
 using System.Threading;
 using Grpc.Net.Client;
+#else
+using System.Collections.Generic;
 #endif
+
 #nullable enable
 namespace EventStore.Client {
 	internal static class ChannelFactory {
@@ -16,13 +20,13 @@ public static ChannelBase CreateChannel(EventStoreClientSettings settings, Uri?
 			address ??= settings.ConnectivitySettings.Address;
 
 #if !GRPC_CORE
-			if (address.Scheme == Uri.UriSchemeHttp ||
-			    !settings.ConnectivitySettings.GossipOverHttps) {
+			if (address.Scheme == Uri.UriSchemeHttp ||!settings.ConnectivitySettings.GossipOverHttps) {
 				//this must be switched on before creation of the HttpMessageHandler
 				AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);
 			}
+
 			return GrpcChannel.ForAddress(address, new GrpcChannelOptions {
-				HttpClient = new HttpClient(settings.CreateHttpMessageHandler?.Invoke() ?? new SocketsHttpHandler(),
+				HttpClient = new HttpClient(CreateHandler(),
 					true) {
 					Timeout = Timeout.InfiniteTimeSpan,
 					DefaultRequestVersion = new Version(2, 0),
@@ -31,8 +35,29 @@ public static ChannelBase CreateChannel(EventStoreClientSettings settings, Uri?
 				Credentials = settings.ChannelCredentials,
 				DisposeHttpClient = true
 			});
+
+			HttpMessageHandler CreateHandler() {
+				if (settings.CreateHttpMessageHandler != null) {
+					return settings.CreateHttpMessageHandler.Invoke();
+				}
+
+				var handler = new SocketsHttpHandler();
+				if (settings.ConnectivitySettings.KeepAlive.HasValue) {
+					handler.KeepAlivePingDelay = settings.ConnectivitySettings.KeepAlive.Value;
+				}
+
+				return handler;
+			}
 #else
-			return new Channel(address.Host, address.Port, settings.ChannelCredentials ?? ChannelCredentials.Insecure);
+			return new Channel(address.Host, address.Port, settings.ChannelCredentials ?? ChannelCredentials.Insecure,
+				GetChannelOptions());
+
+			IEnumerable<ChannelOption> GetChannelOptions() {
+				if (settings.ConnectivitySettings.KeepAlive.HasValue) {
+					yield return new ChannelOption("grpc.keepalive_time_ms",
+						(int)settings.ConnectivitySettings.KeepAlive.Value.TotalMilliseconds);
+				}
+			}
 #endif
 		}
 	}

src/EventStore.Client/EventStoreClientConnectivitySettings.cs

@@ -60,6 +60,10 @@ public class EventStoreClientConnectivitySettings {
 		/// </summary>
 		public NodePreference NodePreference { get; set; }
 
+		/// <summary>
+		/// The optional amount of time to wait after which a keepalive ping is sent on the transport.
+		/// </summary>
+		public TimeSpan? KeepAlive { get; set; }
 
 		/// <summary>
 		/// True if pointing to a single EventStoreDB node.

src/EventStore.Client/EventStoreClientSettings.ConnectionString.cs

@@ -13,9 +13,8 @@ public partial class EventStoreClientSettings {
 		/// </summary>
 		/// <param name="connectionString"></param>
 		/// <returns></returns>
-		public static EventStoreClientSettings Create(string connectionString) {
-			return ConnectionStringParser.Parse(connectionString);
-		}
+		public static EventStoreClientSettings Create(string connectionString) =>
+			ConnectionStringParser.Parse(connectionString);
 
 		private static class ConnectionStringParser {
 			private const string SchemeSeparator = "://";
@@ -28,14 +27,15 @@ private static class ConnectionStringParser {
 			private const string QuestionMark = "?";
 
 			private const string Tls = nameof(Tls);
-			private const string ConnectionName = "ConnectionName";
-			private const string MaxDiscoverAttempts = "MaxDiscoverAttempts";
-			private const string DiscoveryInterval = "DiscoveryInterval";
-			private const string GossipTimeout = "GossipTimeout";
-			private const string NodePreference = "NodePreference";
-			private const string TlsVerifyCert = "TlsVerifyCert";
-			private const string OperationTimeout = "OperationTimeout";
-			private const string ThrowOnAppendFailure = "ThrowOnAppendFailure";
+			private const string ConnectionName = nameof(ConnectionName);
+			private const string MaxDiscoverAttempts = nameof(MaxDiscoverAttempts);
+			private const string DiscoveryInterval = nameof(DiscoveryInterval);
+			private const string GossipTimeout = nameof(GossipTimeout);
+			private const string NodePreference = nameof(NodePreference);
+			private const string TlsVerifyCert = nameof(TlsVerifyCert);
+			private const string OperationTimeout = nameof(OperationTimeout);
+			private const string ThrowOnAppendFailure = nameof(ThrowOnAppendFailure);
+			private const string KeepAlive = nameof(KeepAlive);
 
 			private const string UriSchemeDiscover = "esdb+discover";
 
@@ -53,7 +53,8 @@ private static class ConnectionStringParser {
 					{Tls, typeof(bool)},
 					{TlsVerifyCert, typeof(bool)},
 					{OperationTimeout, typeof(int)},
-					{ThrowOnAppendFailure, typeof(bool)}
+					{ThrowOnAppendFailure, typeof(bool)},
+					{KeepAlive, typeof(int)}
 				};
 
 			public static EventStoreClientSettings Parse(string connectionString) {
@@ -159,24 +160,16 @@ private static EventStoreClientSettings CreateSettings(string scheme, (string us
 					useTls = (bool)tls;
 				}
 
-				if (typedOptions.TryGetValue(TlsVerifyCert, out object tlsVerifyCert)) {
-					if (!(bool)tlsVerifyCert) {
-#if !GRPC_CORE
-						settings.CreateHttpMessageHandler = () => new SocketsHttpHandler {
-							SslOptions = {
-								RemoteCertificateValidationCallback = delegate { return true; }
-							}
-						};
-#endif
-					}
-				}
-
 				if (typedOptions.TryGetValue(OperationTimeout, out object operationTimeout))
 					settings.OperationOptions.TimeoutAfter = TimeSpan.FromMilliseconds((int)operationTimeout);
 
 				if (typedOptions.TryGetValue(ThrowOnAppendFailure, out object throwOnAppendFailure))
 					settings.OperationOptions.ThrowOnAppendFailure = (bool)throwOnAppendFailure;
 
+				if (typedOptions.TryGetValue(KeepAlive, out var keepAliveMs)) {
+					settings.ConnectivitySettings.KeepAlive = TimeSpan.FromMilliseconds((int)keepAliveMs);
+				}
+
 				if (hosts.Length == 1 && scheme != UriSchemeDiscover) {
 					connSettings.Address = hosts[0].ToUri(useTls);
 				} else {
@@ -189,6 +182,22 @@ private static EventStoreClientSettings CreateSettings(string scheme, (string us
 					connSettings.GossipOverHttps = useTls;
 				}
 
+#if !GRPC_CORE
+				settings.CreateHttpMessageHandler = () => {
+					var handler = new SocketsHttpHandler();
+
+					if (typedOptions.TryGetValue(TlsVerifyCert, out var tlsVerifyCert) && !(bool)tlsVerifyCert) {
+						handler.SslOptions.RemoteCertificateValidationCallback = delegate { return true; };
+					}
+
+					if (settings.ConnectivitySettings.KeepAlive.HasValue) {
+						handler.KeepAlivePingDelay = settings.ConnectivitySettings.KeepAlive.Value;
+					}
+
+					return handler;
+				};
+#endif
+
 				return settings;
 			}
 

test/EventStore.Client.Tests/ConnectionStringTests.cs

@@ -89,7 +89,8 @@ public void connection_string_with_duplicate_key_should_throw(string connectionS
 		 InlineData("esdb://user:[email protected]/?discoveryInterval=abcd"),
 		 InlineData("esdb://user:[email protected]/?gossipTimeout=defg"),
 		 InlineData("esdb://user:[email protected]/?tlsVerifyCert=truee"),
-		 InlineData("esdb://user:[email protected]/?nodePreference=blabla")]
+		 InlineData("esdb://user:[email protected]/?nodePreference=blabla"),
+		 InlineData("esdb://user:[email protected]/?keepAlive=blabla")]
 		public void connection_string_with_invalid_settings_should_throw(string connectionString) {
 			Assert.Throws<InvalidSettingException>(() => EventStoreClientSettings.Create(connectionString));
 		}
@@ -107,10 +108,8 @@ public void with_different_node_preferences(string nodePreference, NodePreferenc
 
 		[Fact]
 		public void with_valid_single_node_connection_string() {
-			EventStoreClientSettings settings;
-
-			settings = EventStoreClientSettings.Create(
-				"esdb://user:[email protected]/?maxDiscoverAttempts=13&DiscoveryInterval=37&gossipTimeout=33&nOdEPrEfErence=FoLLoWer&tlsVerifyCert=false");
+			var settings = EventStoreClientSettings.Create(
+				"esdb://user:[email protected]/?maxDiscoverAttempts=13&DiscoveryInterval=37&gossipTimeout=33&nOdEPrEfErence=FoLLoWer&tlsVerifyCert=false&keepAlive=10");
 			Assert.Equal("user", settings.DefaultCredentials.Username);
 			Assert.Equal("pass", settings.DefaultCredentials.Password);
 			Assert.Equal("https://127.0.0.1:2113/", settings.ConnectivitySettings.Address.ToString());
@@ -121,14 +120,15 @@ public void with_valid_single_node_connection_string() {
 			Assert.Equal(37, settings.ConnectivitySettings.DiscoveryInterval.TotalMilliseconds);
 			Assert.Equal(33, settings.ConnectivitySettings.GossipTimeout.TotalMilliseconds);
 			Assert.Equal(NodePreference.Follower, settings.ConnectivitySettings.NodePreference);
+			Assert.Equal(TimeSpan.FromMilliseconds(10), settings.ConnectivitySettings.KeepAlive);
 #if !GRPC_CORE
 #if !GRPC_CORE
 			Assert.NotNull(settings.CreateHttpMessageHandler);
 #endif
 
 #endif
 			settings = EventStoreClientSettings.Create(
-				"esdb://127.0.0.1?connectionName=test&maxDiscoverAttempts=13&DiscoveryInterval=37&nOdEPrEfErence=FoLLoWer&tls=true&tlsVerifyCert=true&operationTimeout=330&throwOnAppendFailure=faLse");
+				"esdb://127.0.0.1?connectionName=test&maxDiscoverAttempts=13&DiscoveryInterval=37&nOdEPrEfErence=FoLLoWer&tls=true&tlsVerifyCert=true&operationTimeout=330&throwOnAppendFailure=faLse&KEepAlive=10");
 			Assert.Null(settings.DefaultCredentials);
 			Assert.Equal("test", settings.ConnectionName);
 			Assert.Equal("https://127.0.0.1:2113/", settings.ConnectivitySettings.Address.ToString());
@@ -139,8 +139,9 @@ public void with_valid_single_node_connection_string() {
 			Assert.Equal(13, settings.ConnectivitySettings.MaxDiscoverAttempts);
 			Assert.Equal(37, settings.ConnectivitySettings.DiscoveryInterval.TotalMilliseconds);
 			Assert.Equal(NodePreference.Follower, settings.ConnectivitySettings.NodePreference);
+			Assert.Equal(TimeSpan.FromMilliseconds(10), settings.ConnectivitySettings.KeepAlive);
 #if !GRPC_CORE
-			Assert.Null(settings.CreateHttpMessageHandler);
+			Assert.NotNull(settings.CreateHttpMessageHandler);
 #endif
 
 			Assert.Equal(330, settings.OperationOptions.TimeoutAfter.Value.TotalMilliseconds);
@@ -153,15 +154,15 @@ public void with_valid_single_node_connection_string() {
 			Assert.Null(settings.ConnectivitySettings.IpGossipSeeds);
 			Assert.Null(settings.ConnectivitySettings.DnsGossipSeeds);
 			Assert.True(settings.ConnectivitySettings.GossipOverHttps);
+			Assert.Null(settings.ConnectivitySettings.KeepAlive);
 #if !GRPC_CORE
-			Assert.Null(settings.CreateHttpMessageHandler);
+			Assert.NotNull(settings.CreateHttpMessageHandler);
 #endif
 		}
 
 		[Fact]
 		public void with_default_settings() {
-			EventStoreClientSettings settings;
-			settings = EventStoreClientSettings.Create("esdb://hostname:4321/");
+			var settings = EventStoreClientSettings.Create("esdb://hostname:4321/");
 
 			Assert.Null(settings.ConnectionName);
 			Assert.Equal(EventStoreClientConnectivitySettings.Default.Address.Scheme,
@@ -179,18 +180,18 @@ public void with_default_settings() {
 				settings.ConnectivitySettings.NodePreference);
 			Assert.Equal(EventStoreClientConnectivitySettings.Default.GossipOverHttps,
 				settings.ConnectivitySettings.GossipOverHttps);
-			Assert.Equal(EventStoreClientOperationOptions.Default.TimeoutAfter.Value.TotalMilliseconds,
-				settings.OperationOptions.TimeoutAfter.Value.TotalMilliseconds);
+			Assert.Equal(EventStoreClientOperationOptions.Default.TimeoutAfter!.Value.TotalMilliseconds,
+				settings.OperationOptions.TimeoutAfter!.Value.TotalMilliseconds);
 			Assert.Equal(EventStoreClientOperationOptions.Default.ThrowOnAppendFailure,
 				settings.OperationOptions.ThrowOnAppendFailure);
+			Assert.Equal(EventStoreClientConnectivitySettings.Default.KeepAlive,
+				settings.ConnectivitySettings.KeepAlive);
 		}
 
 		[Fact]
 		public void with_valid_cluster_connection_string() {
-			EventStoreClientSettings settings;
-
-			settings = EventStoreClientSettings.Create(
-				"esdb://user:[email protected],127.0.0.2:3321,127.0.0.3/?maxDiscoverAttempts=13&DiscoveryInterval=37&nOdEPrEfErence=FoLLoWer&tlsVerifyCert=false");
+			var settings = EventStoreClientSettings.Create(
+				"esdb://user:[email protected],127.0.0.2:3321,127.0.0.3/?maxDiscoverAttempts=13&DiscoveryInterval=37&nOdEPrEfErence=FoLLoWer&tlsVerifyCert=false&KEepAlive=10");
 			Assert.Equal("user", settings.DefaultCredentials.Username);
 			Assert.Equal("pass", settings.DefaultCredentials.Password);
 			Assert.NotEmpty(settings.ConnectivitySettings.GossipSeeds);
@@ -207,13 +208,14 @@ public void with_valid_cluster_connection_string() {
 			Assert.Equal(13, settings.ConnectivitySettings.MaxDiscoverAttempts);
 			Assert.Equal(37, settings.ConnectivitySettings.DiscoveryInterval.TotalMilliseconds);
 			Assert.Equal(NodePreference.Follower, settings.ConnectivitySettings.NodePreference);
+			Assert.Equal(TimeSpan.FromMilliseconds(10), settings.ConnectivitySettings.KeepAlive);
 #if !GRPC_CORE
 			Assert.NotNull(settings.CreateHttpMessageHandler);
 #endif
 
 
 			settings = EventStoreClientSettings.Create(
-				"esdb://user:pass@host1,host2:3321,127.0.0.3/?tls=false&maxDiscoverAttempts=13&DiscoveryInterval=37&nOdEPrEfErence=FoLLoWer&tlsVerifyCert=false");
+				"esdb://user:pass@host1,host2:3321,127.0.0.3/?tls=false&maxDiscoverAttempts=13&DiscoveryInterval=37&nOdEPrEfErence=FoLLoWer&tlsVerifyCert=false&KEepAlive=10");
 			Assert.Equal("user", settings.DefaultCredentials.Username);
 			Assert.Equal("pass", settings.DefaultCredentials.Password);
 			Assert.NotEmpty(settings.ConnectivitySettings.GossipSeeds);
@@ -230,6 +232,7 @@ public void with_valid_cluster_connection_string() {
 			Assert.Equal(13, settings.ConnectivitySettings.MaxDiscoverAttempts);
 			Assert.Equal(37, settings.ConnectivitySettings.DiscoveryInterval.TotalMilliseconds);
 			Assert.Equal(NodePreference.Follower, settings.ConnectivitySettings.NodePreference);
+			Assert.Equal(TimeSpan.FromMilliseconds(10), settings.ConnectivitySettings.KeepAlive);
 #if !GRPC_CORE
 			Assert.NotNull(settings.CreateHttpMessageHandler);
 #endif
@@ -264,19 +267,19 @@ public void with_different_tls_verify_cert_settings() {
 			EventStoreClientSettings settings;
 
 			settings = EventStoreClientSettings.Create("esdb://127.0.0.1/");
-			Assert.Null(settings.CreateHttpMessageHandler);
+			Assert.NotNull(settings.CreateHttpMessageHandler);
 
 			settings = EventStoreClientSettings.Create("esdb://127.0.0.1/?tlsVerifyCert=TrUe");
-			Assert.Null(settings.CreateHttpMessageHandler);
+			Assert.NotNull(settings.CreateHttpMessageHandler);
 
 			settings = EventStoreClientSettings.Create("esdb://127.0.0.1/?tlsVerifyCert=FaLsE");
 			Assert.NotNull(settings.CreateHttpMessageHandler);
 
 			settings = EventStoreClientSettings.Create("esdb://127.0.0.1,127.0.0.2:3321,127.0.0.3/");
-			Assert.Null(settings.CreateHttpMessageHandler);
+			Assert.NotNull(settings.CreateHttpMessageHandler);
 
 			settings = EventStoreClientSettings.Create("esdb://127.0.0.1,127.0.0.2:3321,127.0.0.3/?tlsVerifyCert=true");
-			Assert.Null(settings.CreateHttpMessageHandler);
+			Assert.NotNull(settings.CreateHttpMessageHandler);
 
 			settings = EventStoreClientSettings.Create(
 				"esdb://127.0.0.1,127.0.0.2:3321,127.0.0.3/?tlsVerifyCert=false");