Make all ConnectionStringBuilder properties non-null. Fixes #837

Author: bgrainger

src/MySqlConnector/Core/ConnectionSettings.cs

@@ -21,6 +21,7 @@ public ConnectionSettings(MySqlConnectionStringBuilder csb)
 					throw new MySqlException("Cannot find Unix Socket at " + csb.Server);
 				ConnectionProtocol = MySqlConnectionProtocol.UnixSocket;
 				UnixSocket = Path.GetFullPath(csb.Server);
+				PipeName = "";
 			}
 			else if (csb.ConnectionProtocol == MySqlConnectionProtocol.NamedPipe)
 			{
@@ -40,6 +41,7 @@ public ConnectionSettings(MySqlConnectionStringBuilder csb)
 				HostNames = csb.Server.Split(',');
 				LoadBalance = csb.LoadBalance;
 				Port = (int) csb.Port;
+				PipeName = "";
 			}
 
 			UserID = csb.UserID;
@@ -56,7 +58,7 @@ public ConnectionSettings(MySqlConnectionStringBuilder csb)
 			CertificateStoreLocation = csb.CertificateStoreLocation;
 			CertificateThumbprint = csb.CertificateThumbprint;
 
-			if (csb.TlsVersion is null)
+			if (csb.TlsVersion.Length == 0)
 			{
 				TlsVersions = Utility.GetDefaultSslProtocols();
 			}
@@ -155,21 +157,21 @@ private static MySqlGuidFormat GetEffectiveGuidFormat(MySqlGuidFormat guidFormat
 		public IReadOnlyList<string>? HostNames { get; }
 		public MySqlLoadBalance LoadBalance { get; }
 		public int Port { get; }
-		public string? PipeName { get; }
+		public string PipeName { get; }
 		public string? UnixSocket { get; }
 		public string UserID { get; }
 		public string Password { get; }
 		public string Database { get; }
 
 		// SSL/TLS Options
 		public MySqlSslMode SslMode { get; }
-		public string? CertificateFile { get; }
-		public string? CertificatePassword { get; }
-		public string? CACertificateFile { get; }
-		public string? SslCertificateFile { get; }
-		public string? SslKeyFile { get; }
+		public string CertificateFile { get; }
+		public string CertificatePassword { get; }
+		public string CACertificateFile { get; }
+		public string SslCertificateFile { get; }
+		public string SslKeyFile { get; }
 		public MySqlCertificateStoreLocation CertificateStoreLocation { get; }
-		public string? CertificateThumbprint { get; }
+		public string CertificateThumbprint { get; }
 		public SslProtocols TlsVersions { get; }
 
 		// Connection Pooling Options
@@ -186,7 +188,7 @@ private static MySqlGuidFormat GetEffectiveGuidFormat(MySqlGuidFormat guidFormat
 		public bool AllowPublicKeyRetrieval { get; }
 		public bool AllowUserVariables { get; }
 		public bool AllowZeroDateTime { get; }
-		public string? ApplicationName { get; }
+		public string ApplicationName { get; }
 		public bool AutoEnlist { get; }
 		public int ConnectionTimeout { get; }
 		public bool ConvertZeroDateTime { get; }
@@ -200,8 +202,8 @@ private static MySqlGuidFormat GetEffectiveGuidFormat(MySqlGuidFormat guidFormat
 		public uint Keepalive { get; }
 		public bool NoBackslashEscapes { get; }
 		public bool PersistSecurityInfo { get; }
-		public string? ServerRsaPublicKeyFile { get; }
-		public string? ServerSPN { get; }
+		public string ServerRsaPublicKeyFile { get; }
+		public string ServerSPN { get; }
 		public bool TreatTinyAsBoolean { get; }
 		public bool UseAffectedRows { get; }
 		public bool UseCompression { get; }

src/MySqlConnector/Core/ServerSession.cs

@@ -685,7 +685,7 @@ private async Task<PayloadData> SendEncryptedPasswordAsync(
 
 		private async Task<string> GetRsaPublicKeyAsync(string switchRequestName, ConnectionSettings cs, IOBehavior ioBehavior, CancellationToken cancellationToken)
 		{
-			if (!string.IsNullOrEmpty(cs.ServerRsaPublicKeyFile))
+			if (cs.ServerRsaPublicKeyFile.Length != 0)
 			{
 				try
 				{
@@ -1022,7 +1022,7 @@ private async Task<bool> OpenNamedPipeAsync(ConnectionSettings cs, int startTick
 #else
 			if (Log.IsInfoEnabled())
 				Log.Info("Session{0} connecting to NamedPipe '{1}' on Server '{2}'", m_logArguments[0], cs.PipeName, cs.HostNames![0]);
-			var namedPipeStream = new NamedPipeClientStream(cs.HostNames![0], cs.PipeName!, PipeDirection.InOut, PipeOptions.Asynchronous);
+			var namedPipeStream = new NamedPipeClientStream(cs.HostNames![0], cs.PipeName, PipeDirection.InOut, PipeOptions.Asynchronous);
 			var timeout = Math.Max(1, cs.ConnectionTimeoutMilliseconds - unchecked(Environment.TickCount - startTickCount));
 			try
 			{
@@ -1076,7 +1076,7 @@ private async Task InitSslAsync(ProtocolCapabilities serverCapabilities, Connect
 					var store = new X509Store(StoreName.My, storeLocation);
 					store.Open(OpenFlags.ReadOnly | OpenFlags.OpenExistingOnly);
 
-					if (cs.CertificateThumbprint is null)
+					if (cs.CertificateThumbprint.Length == 0)
 					{
 						if (store.Certificates.Count == 0)
 						{
@@ -1108,7 +1108,7 @@ private async Task InitSslAsync(ProtocolCapabilities serverCapabilities, Connect
 				}
 			}
 
-			if (cs.SslCertificateFile is not null && cs.SslKeyFile is not null)
+			if (cs.SslCertificateFile.Length != 0 && cs.SslKeyFile.Length != 0)
 			{
 #if !NETSTANDARD1_3 && !NETSTANDARD2_0
 				m_logArguments[1] = cs.SslKeyFile;
@@ -1182,7 +1182,7 @@ private async Task InitSslAsync(ProtocolCapabilities serverCapabilities, Connect
 				throw new NotSupportedException("SslCert and SslKey connection string options are not supported in netstandard1.3 or netstandard2.0.");
 #endif
 			}
-			else if (cs.CertificateFile is not null)
+			else if (cs.CertificateFile.Length != 0)
 			{
 				try
 				{
@@ -1208,7 +1208,7 @@ private async Task InitSslAsync(ProtocolCapabilities serverCapabilities, Connect
 			}
 
 			X509Chain? caCertificateChain = null;
-			if (cs.CACertificateFile is not null)
+			if (cs.CACertificateFile.Length != 0)
 			{
 				X509Chain? certificateChain = new()
 				{
@@ -1511,7 +1511,7 @@ private void VerifyState(State state1, State state2, State state3)
 
 		internal SslProtocols SslProtocol => m_sslStream?.SslProtocol ?? SslProtocols.None;
 
-		private byte[] CreateConnectionAttributes(string? programName)
+		private byte[] CreateConnectionAttributes(string programName)
 		{
 			Log.Debug("Session{0} creating connection attributes", m_logArguments);
 			var attributesWriter = new ByteBufferWriter();
@@ -1544,7 +1544,7 @@ private byte[] CreateConnectionAttributes(string? programName)
 			using var process = Process.GetCurrentProcess();
 			attributesWriter.WriteLengthEncodedString("_pid");
 			attributesWriter.WriteLengthEncodedString(process.Id.ToString(CultureInfo.InvariantCulture));
-			if (!string.IsNullOrEmpty(programName))
+			if (programName.Length != 0)
 			{
 				attributesWriter.WriteLengthEncodedString("program_name");
 				attributesWriter.WriteLengthEncodedString(programName!);