Add Support for Single DNS Gossip Seed

.github/workflows/ci.yml

@@ -50,7 +50,7 @@ jobs:
       run: |
         docker pull docker.pkg.github.com/eventstore/eventstore/eventstore:${{ matrix.docker-tag }}
     - name: Install Dotnet
-      uses: actions/setup-dotnet@v1.4.0
+      uses: actions/setup-dotnet@v1
       with:
         dotnet-version: ${{ env.DOTNET_SDK_VERSION }}
     - name: Compile
@@ -103,7 +103,7 @@ jobs:
       run: |
         git fetch --prune --unshallow
     - name: Setup Dotnet
-      uses: actions/setup-dotnet@v1.4.0
+      uses: actions/setup-dotnet@v1
       with:
         dotnet-version: ${{ env.DOTNET_SDK_VERSION }}
     - name: Dotnet Pack

.github/workflows/regression.yml

@@ -49,7 +49,7 @@ jobs:
       run: |
         git fetch --prune --unshallow
     - name: Install Dotnet
-      uses: actions/setup-dotnet@v1.4.0
+      uses: actions/setup-dotnet@v1
       with:
         dotnet-version: ${{ env.DOTNET_SDK_VERSION }}
     - name: Compile

src/EventStore.Client/ClusterAwareHttpHandler.cs

@@ -65,7 +65,7 @@ protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage
 				return await base.SendAsync(request, cancellationToken).ConfigureAwait(false);
 			} catch (Exception) {
 				Interlocked.CompareExchange(ref _endpoint,
-					new Lazy<Task<EndPoint>>(() => _endpointDiscoverer.DiscoverAsync(),
+					new Lazy<Task<EndPoint>>(_endpointDiscoverer.DiscoverAsync,
 						LazyThreadSafetyMode.ExecutionAndPublication), endpointResolver);
 
 				throw;

src/EventStore.Client/EventStoreClientSettings.ConnectionString.cs

@@ -24,21 +24,35 @@ private static class ConnectionStringParser {
 			private const string Ampersand = "&";
 			private const string Equal = "=";
 			private const string QuestionMark = "?";
-			private static readonly string[] Schemes = { "esdb" };
+
+			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 UriSchemeDiscover = "esdb+discover";
+
+			private static readonly string[] Schemes = {"esdb", UriSchemeDiscover};
 			private static readonly int DefaultPort = EventStoreClientConnectivitySettings.Default.Address.Port;
 			private static readonly bool DefaultUseTls = true;
 
-			private static readonly Dictionary<string, Type> SettingsType = new Dictionary<string, Type> (StringComparer.InvariantCultureIgnoreCase) {
-				{"ConnectionName", typeof(string)},
-				{"MaxDiscoverAttempts", typeof(int)},
-				{"DiscoveryInterval", typeof(int)},
-				{"GossipTimeout", typeof(int)},
-				{"NodePreference", typeof(string)},
-				{"Tls", typeof(bool)},
-				{"TlsVerifyCert", typeof(bool)},
-				{"OperationTimeout", typeof(int)},
-				{"ThrowOnAppendFailure", typeof(bool)}
-			};
+			private static readonly Dictionary<string, Type> SettingsType =
+				new Dictionary<string, Type>(StringComparer.InvariantCultureIgnoreCase) {
+					{ConnectionName, typeof(string)},
+					{MaxDiscoverAttempts, typeof(int)},
+					{DiscoveryInterval, typeof(int)},
+					{GossipTimeout, typeof(int)},
+					{NodePreference, typeof(string)},
+					{Tls, typeof(bool)},
+					{TlsVerifyCert, typeof(bool)},
+					{OperationTimeout, typeof(int)},
+					{ThrowOnAppendFailure, typeof(bool)}
+				};
 
 			public static EventStoreClientSettings Parse(string connectionString) {
 				var currentIndex = 0;
@@ -57,23 +71,26 @@ public static EventStoreClientSettings Parse(string connectionString) {
 
 
 				var slashIndex = connectionString.IndexOf(Slash, currentIndex, StringComparison.Ordinal);
-				var questionMarkIndex = connectionString.IndexOf(QuestionMark, Math.Max(currentIndex, slashIndex), StringComparison.Ordinal);
+				var questionMarkIndex = connectionString.IndexOf(QuestionMark, Math.Max(currentIndex, slashIndex),
+					StringComparison.Ordinal);
 				var endIndex = connectionString.Length;
 
 				//for simpler substring operations:
 				if (slashIndex == -1) slashIndex = int.MaxValue;
 				if (questionMarkIndex == -1) questionMarkIndex = int.MaxValue;
 
 				var hostSeparatorIndex = Math.Min(Math.Min(slashIndex, questionMarkIndex), endIndex);
-				var hosts = ParseHosts(connectionString.Substring(currentIndex,hostSeparatorIndex - currentIndex));
+				var hosts = ParseHosts(connectionString.Substring(currentIndex, hostSeparatorIndex - currentIndex));
 				currentIndex = hostSeparatorIndex;
 
 				string path = "";
 				if (slashIndex != int.MaxValue)
-					path = connectionString.Substring(currentIndex,Math.Min(questionMarkIndex, endIndex) - currentIndex);
+					path = connectionString.Substring(currentIndex,
+						Math.Min(questionMarkIndex, endIndex) - currentIndex);
 
 				if (path != "" && path != "/")
-					throw new ConnectionStringParseException($"The specified path must be either an empty string or a forward slash (/) but the following path was found instead: '{path}'");
+					throw new ConnectionStringParseException(
+						$"The specified path must be either an empty string or a forward slash (/) but the following path was found instead: '{path}'");
 
 				var options = new Dictionary<string, string>();
 				if (questionMarkIndex != int.MaxValue) {
@@ -84,7 +101,8 @@ public static EventStoreClientSettings Parse(string connectionString) {
 				return CreateSettings(scheme, userInfo, hosts, options);
 			}
 
-			private static EventStoreClientSettings CreateSettings(string scheme, (string user, string pass) userInfo, EndPoint[] hosts, Dictionary<string, string> options) {
+			private static EventStoreClientSettings CreateSettings(string scheme, (string user, string pass) userInfo,
+				EndPoint[] hosts, Dictionary<string, string> options) {
 				var settings = new EventStoreClientSettings {
 					ConnectivitySettings = EventStoreClientConnectivitySettings.Default,
 					OperationOptions = EventStoreClientOperationOptions.Default
@@ -94,61 +112,52 @@ private static EventStoreClientSettings CreateSettings(string scheme, (string us
 					settings.DefaultCredentials = new UserCredentials(userInfo.user, userInfo.pass);
 
 				var typedOptions = new Dictionary<string, object>(StringComparer.InvariantCultureIgnoreCase);
-				foreach (var option in options) {
-					if (!SettingsType.TryGetValue(option.Key, out var type)) throw new InvalidSettingException($"Unknown option: {option.Key}");
-					if(type == typeof(int)){
-						if (!int.TryParse(option.Value, out var intValue))
-							throw new InvalidSettingException($"{option.Key} must be an integer value");
-						typedOptions.Add(option.Key, intValue);
+				foreach (var (key, value) in options) {
+					if (!SettingsType.TryGetValue(key, out var type))
+						throw new InvalidSettingException($"Unknown option: {key}");
+					if (type == typeof(int)) {
+						if (!int.TryParse(value, out var intValue))
+							throw new InvalidSettingException($"{key} must be an integer value");
+						typedOptions.Add(key, intValue);
 					} else if (type == typeof(bool)) {
-						if (!bool.TryParse(option.Value, out var boolValue))
-							throw new InvalidSettingException($"{option.Key} must be either true or false");
-						typedOptions.Add(option.Key, boolValue);
+						if (!bool.TryParse(value, out var boolValue))
+							throw new InvalidSettingException($"{key} must be either true or false");
+						typedOptions.Add(key, boolValue);
 					} else if (type == typeof(string)) {
-						typedOptions.Add(option.Key, option.Value);
+						typedOptions.Add(key, value);
 					}
 				}
 
-				if (typedOptions.TryGetValue("ConnectionName", out object connectionName))
-					settings.ConnectionName = (string) connectionName;
+				if (typedOptions.TryGetValue(ConnectionName, out object connectionName))
+					settings.ConnectionName = (string)connectionName;
 
 				var connSettings = settings.ConnectivitySettings;
 
-				if (typedOptions.TryGetValue("MaxDiscoverAttempts", out object maxDiscoverAttempts))
+				if (typedOptions.TryGetValue(MaxDiscoverAttempts, out object maxDiscoverAttempts))
 					connSettings.MaxDiscoverAttempts = (int)maxDiscoverAttempts;
 
-				if (typedOptions.TryGetValue("DiscoveryInterval", out object discoveryInterval))
+				if (typedOptions.TryGetValue(DiscoveryInterval, out object discoveryInterval))
 					connSettings.DiscoveryInterval = TimeSpan.FromMilliseconds((int)discoveryInterval);
 
-				if (typedOptions.TryGetValue("GossipTimeout", out object gossipTimeout))
+				if (typedOptions.TryGetValue(GossipTimeout, out object gossipTimeout))
 					connSettings.GossipTimeout = TimeSpan.FromMilliseconds((int)gossipTimeout);
 
-				if (typedOptions.TryGetValue("NodePreference", out object nodePreference)) {
-					var nodePreferenceLowerCase = ((string)nodePreference).ToLowerInvariant();
-					switch (nodePreferenceLowerCase) {
-						case "leader":
-							connSettings.NodePreference = NodePreference.Leader;
-							break;
-						case "follower":
-							connSettings.NodePreference = NodePreference.Follower;
-							break;
-						case "random":
-							connSettings.NodePreference = NodePreference.Random;
-							break;
-						case "readonlyreplica":
-							connSettings.NodePreference = NodePreference.ReadOnlyReplica;
-							break;
-						default:
-							throw new InvalidSettingException($"Invalid NodePreference: {nodePreference}");
-					}
+				if (typedOptions.TryGetValue(NodePreference, out object nodePreference)) {
+					connSettings.NodePreference = ((string)nodePreference).ToLowerInvariant() switch {
+						"leader" => EventStore.Client.NodePreference.Leader,
+						"follower" => EventStore.Client.NodePreference.Follower,
+						"random" => EventStore.Client.NodePreference.Random,
+						"readonlyreplica" => EventStore.Client.NodePreference.ReadOnlyReplica,
+						_ => throw new InvalidSettingException($"Invalid NodePreference: {nodePreference}")
+					};
 				}
 
 				var useTls = DefaultUseTls;
-				if(typedOptions.TryGetValue("Tls", out object tls)) {
+				if (typedOptions.TryGetValue(Tls, out object tls)) {
 					useTls = (bool)tls;
 				}
 
-				if (typedOptions.TryGetValue("TlsVerifyCert", out object tlsVerifyCert)) {
+				if (typedOptions.TryGetValue(TlsVerifyCert, out object tlsVerifyCert)) {
 					if (!(bool)tlsVerifyCert) {
 #if NETCOREAPP3_1
 						settings.CreateHttpMessageHandler = () => new SocketsHttpHandler {
@@ -164,32 +173,31 @@ private static EventStoreClientSettings CreateSettings(string scheme, (string us
 					}
 				}
 
-				if(typedOptions.TryGetValue("OperationTimeout", out object operationTimeout))
-					settings.OperationOptions.TimeoutAfter = TimeSpan.FromMilliseconds((int) operationTimeout);
+				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(ThrowOnAppendFailure, out object throwOnAppendFailure))
+					settings.OperationOptions.ThrowOnAppendFailure = (bool)throwOnAppendFailure;
 
-				if (hosts.Length == 1) {
-					connSettings.Address = new Uri(hosts[0].ToHttpUrl(useTls?Uri.UriSchemeHttps:Uri.UriSchemeHttp));
+				if (hosts.Length == 1 && scheme != UriSchemeDiscover) {
+					connSettings.Address = new Uri(hosts[0].ToHttpUrl(useTls ? Uri.UriSchemeHttps : Uri.UriSchemeHttp));
 				} else {
 					if (hosts.Any(x => x is DnsEndPoint))
-						connSettings.DnsGossipSeeds = hosts.Select(x => new DnsEndPoint(x.GetHost(), x.GetPort())).ToArray();
+						connSettings.DnsGossipSeeds =
+							Array.ConvertAll(hosts, x => new DnsEndPoint(x.GetHost(), x.GetPort()));
 					else
-						connSettings.IpGossipSeeds = hosts.Select(x => x as IPEndPoint).ToArray();
+						connSettings.IpGossipSeeds = Array.ConvertAll(hosts, x => x as IPEndPoint);
 
 					connSettings.GossipOverHttps = useTls;
 				}
 
 				return settings;
 			}
 
-			private static string ParseScheme(string s) {
-				if (!Schemes.Contains(s)) throw new InvalidSchemeException(s, Schemes);
-				return s;
-			}
+			private static string ParseScheme(string s) =>
+				!Schemes.Contains(s) ? throw new InvalidSchemeException(s, Schemes) : s;
 
-			private static (string,string) ParseUserInfo(string s) {
+			private static (string, string) ParseUserInfo(string s) {
 				var tokens = s.Split(Colon);
 				if (tokens.Length != 2) throw new InvalidUserCredentialsException(s);
 				return (tokens[0], tokens[1]);
@@ -202,14 +210,12 @@ private static EndPoint[] ParseHosts(string s) {
 					var hostPortToken = hostToken.Split(Colon);
 					string host;
 					int port;
-					switch (hostPortToken.Length)
-					{
+					switch (hostPortToken.Length) {
 						case 1:
 							host = hostPortToken[0];
 							port = DefaultPort;
 							break;
-						case 2:
-						{
+						case 2: {
 							host = hostPortToken[0];
 							if (!int.TryParse(hostPortToken[1], out port))
 								throw new InvalidHostException(hostToken);
@@ -244,10 +250,11 @@ private static Dictionary<string, string> ParseKeyValuePairs(string s) {
 						throw new DuplicateKeyException(key);
 					}
 				}
+
 				return options;
 			}
 
-			private static (string,string) ParseKeyValuePair(string s) {
+			private static (string, string) ParseKeyValuePair(string s) {
 				var keyValueToken = s.Split(Equal);
 				if (keyValueToken.Length != 2) {
 					throw new InvalidKeyValuePairException(s);

test/EventStore.Client.Tests.Common/EventStoreClientFixtureBase.cs

@@ -72,25 +72,14 @@ protected EventStoreClientFixtureBase(EventStoreClientSettings? clientSettings,
 			IDictionary<string, string>? env = null) {
 			_disposables = new List<IDisposable>();
 			ServicePointManager.ServerCertificateValidationCallback = delegate { return true; };
-			Settings = clientSettings ?? new EventStoreClientSettings {
-				CreateHttpMessageHandler = () => new SocketsHttpHandler {
-					SslOptions = {
-						RemoteCertificateValidationCallback = delegate { return true; }
-					}
-				},
-				OperationOptions = {
-					TimeoutAfter = Debugger.IsAttached
-						? new TimeSpan?()
-						: TimeSpan.FromSeconds(30)
-				},
-				ConnectivitySettings = {
-					Address = new UriBuilder {
-						Scheme = Uri.UriSchemeHttps,
-						Port = 2113
-					}.Uri
-				},
-				LoggerFactory = new SerilogLoggerFactory()
-			};
+
+			Settings = clientSettings ?? EventStoreClientSettings.Create("esdb://localhost:2113/?tlsVerifyCert=false");
+
+			Settings.OperationOptions.TimeoutAfter = Debugger.IsAttached
+				? new TimeSpan?()
+				: TimeSpan.FromSeconds(30);
+
+			Settings.LoggerFactory ??= new SerilogLoggerFactory();
 
 			TestServer = new EventStoreTestServer(Settings.ConnectivitySettings.Address, env);
 		}