Restore behavior of _Server_ and _Port_ in client options (#2009)

* Restore old server and port behavior

* Fix unit test

.github/workflows/ReleaseNotes.md

@@ -1,2 +1 @@
-* [Client] Fix _None of the discovered or specified addresses match the socket address family._ (#1997).
-* [Client] Remove the obsolete attribute from the _WithConnectionUri_ methods (#1979).
+* [Client] Restored _Server_ and _Port_ behavior of client options (#2005).

Source/MQTTnet.Tests/Clients/MqttClient/MqttClient_Tests.cs

@@ -6,6 +6,7 @@ using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
+using System.Net;
 using System.Net.Sockets;
 using System.Text;
 using System.Threading;
@@ -925,5 +926,54 @@ namespace MQTTnet.Tests.Clients.MqttClient
                 Assert.IsFalse(disconnectedFired);
             }
         }
+
+        [TestMethod]
+        public void Backward_compatible_TCP_options()
+        {
+            var options = new MqttClientOptionsBuilder().WithTcpServer("host", 3).Build();
+
+            Assert.AreEqual("host", ((MqttClientTcpOptions)options.ChannelOptions).Server);
+            Assert.AreEqual(3, ((MqttClientTcpOptions)options.ChannelOptions).Port);
+
+            options = new MqttClientOptions
+            {
+                ChannelOptions = new MqttClientTcpOptions
+                {
+                    Server = "host",
+                    Port = 3
+                }
+            };
+
+            Assert.AreEqual("host:3", options.ChannelOptions.ToString());
+            Assert.AreEqual("host", ((MqttClientTcpOptions)options.ChannelOptions).Server);
+            Assert.AreEqual(3, ((MqttClientTcpOptions)options.ChannelOptions).Port);
+
+            options = new MqttClientOptionsBuilder().WithEndPoint(new DnsEndPoint("host", 3)).Build();
+            Assert.AreEqual("Unspecified/host:3", options.ChannelOptions.ToString());
+            Assert.AreEqual("host", ((MqttClientTcpOptions)options.ChannelOptions).Server);
+            Assert.AreEqual(3, ((MqttClientTcpOptions)options.ChannelOptions).Port);
+
+            options = new MqttClientOptionsBuilder().WithTcpServer("host").Build();
+
+            Assert.AreEqual("host", ((MqttClientTcpOptions)options.ChannelOptions).Server);
+            Assert.AreEqual(1883, ((MqttClientTcpOptions)options.ChannelOptions).Port);
+            Assert.AreEqual("Unspecified/host:1883", options.ChannelOptions.ToString());
+
+            options = new MqttClientOptionsBuilder().WithTlsOptions(o => o.UseTls()).WithTcpServer("host").Build();
+
+            Assert.AreEqual("host", ((MqttClientTcpOptions)options.ChannelOptions).Server);
+            Assert.AreEqual(8883, ((MqttClientTcpOptions)options.ChannelOptions).Port);
+
+            options = new MqttClientOptions
+            {
+                ChannelOptions = new MqttClientTcpOptions
+                {
+                    Server = "host"
+                }
+            };
+
+            Assert.AreEqual("host", ((MqttClientTcpOptions)options.ChannelOptions).Server);
+            Assert.AreEqual(null, ((MqttClientTcpOptions)options.ChannelOptions).Port);
+        }
     }
 }

Source/MQTTnet/Client/Options/MqttClientTcpOptions.cs

@@ -5,11 +5,13 @@
 using System;
 using System.Net;
 using System.Net.Sockets;
+using MQTTnet.Protocol;
 
 namespace MQTTnet.Client
 {
     public sealed class MqttClientTcpOptions : IMqttClientChannelOptions
     {
+        EndPoint _remoteEndpoint;
         public AddressFamily AddressFamily { get; set; } = AddressFamily.Unspecified;
 
         public int BufferSize { get; set; } = 8192;
@@ -49,13 +51,56 @@ namespace MQTTnet.Client
         /// </summary>
         public ProtocolType ProtocolType { get; set; } = ProtocolType.Tcp;
 
-        public EndPoint RemoteEndpoint { get; set; }
+        public EndPoint RemoteEndpoint
+        {
+            get => _remoteEndpoint;
+            set
+            {
+                _remoteEndpoint = value;
+
+                if (_remoteEndpoint is DnsEndPoint dnsEndPoint)
+                {
+                    Server = dnsEndPoint.Host;
+                    Port = dnsEndPoint.Port;
+                }
+                else if (_remoteEndpoint is IPEndPoint ipEndPoint)
+                {
+                    Server = ipEndPoint.Address.ToString();
+                    Port = ipEndPoint.Port;
+                }
+            }
+        }
 
         public MqttClientTlsOptions TlsOptions { get; set; } = new MqttClientTlsOptions();
 
         public override string ToString()
         {
-            return RemoteEndpoint?.ToString() ?? string.Empty;
+            if (RemoteEndpoint != null)
+            {
+                return RemoteEndpoint.ToString();
+            }
+
+            if (!string.IsNullOrEmpty(Server))
+            {
+                return $"{Server}:{GetPort()}";
+            }
+
+            return string.Empty;
+        }
+
+        int GetPort()
+        {
+            if (Port.HasValue)
+            {
+                return Port.Value;
+            }
+
+            if (TlsOptions?.UseTls == true)
+            {
+                return MqttPorts.Secure;
+            }
+
+            return MqttPorts.Default;
         }
     }
 }