Refactor logging to allow a loggerfactory per session (#1673)

* Refactor logging to allow a loggerfactory per session specified in the ConnectionInfo.

This commit introduces an `ILoggerFactory` to various classes, replacing the static logger factory with an instance-based approach for more flexible and session-specific logging. These changes improve the logging framework's flexibility and maintainability and allow unit testing of logging.

* Improvements bases on feedback. Fixed tests. Added documentation.

* Update src/Renci.SshNet/ConnectionInfo.cs

---------

Co-authored-by: Rob Hague <[email protected]>

Author: desdesdes

docfx/logging.md

@@ -1,7 +1,31 @@
 Logging
 =================
 
-SSH.NET uses the [Microsoft.Extensions.Logging](https://learn.microsoft.com/dotnet/core/extensions/logging) API to log diagnostic messages. In order to access the log messages of SSH.NET in your own application for diagnosis, register your own `ILoggerFactory` before using the SSH.NET APIs, for example:
+SSH.NET uses the [Microsoft.Extensions.Logging](https://learn.microsoft.com/dotnet/core/extensions/logging) API to log diagnostic messages. 
+
+It is possible to specify a logger in the `ConnectionInfo`, for example:
+
+```cs
+using Microsoft.Extensions.Logging;
+
+ILoggerFactory loggerFactory = LoggerFactory.Create(builder =>
+{
+    builder.SetMinimumLevel(LogLevel.Debug);
+    builder.AddConsole();
+});
+
+var connectionInfo = new ConnectionInfo("sftp.foo.com",
+                                        "guest",
+                                        new PasswordAuthenticationMethod("guest", "pwd"));
+										
+connectionInfo.LoggerFactory = loggerFactory;
+using (var client = new SftpClient(connectionInfo))
+{
+    client.Connect();
+}
+```
+
+You can also register an application-wide `ILoggerFactory` before using the SSH.NET APIs, this will be used as a fallback if the `ConnectionInfo` is not set, for example:
 
 ```cs
 using Microsoft.Extensions.Logging;

src/Renci.SshNet/BaseClient.cs

@@ -192,7 +192,7 @@ private protected BaseClient(ConnectionInfo connectionInfo, bool ownsConnectionI
             _connectionInfo = connectionInfo;
             _ownsConnectionInfo = ownsConnectionInfo;
             _serviceFactory = serviceFactory;
-            _logger = SshNetLoggingConfiguration.LoggerFactory.CreateLogger(GetType());
+            _logger = (connectionInfo.LoggerFactory ?? SshNetLoggingConfiguration.LoggerFactory).CreateLogger(GetType());
             _keepAliveInterval = Timeout.InfiniteTimeSpan;
         }
 

src/Renci.SshNet/Channels/Channel.cs

@@ -84,7 +84,7 @@ protected Channel(ISession session, uint localChannelNumber, uint localWindowSiz
             LocalChannelNumber = localChannelNumber;
             LocalPacketSize = localPacketSize;
             LocalWindowSize = localWindowSize;
-            _logger = SshNetLoggingConfiguration.LoggerFactory.CreateLogger(GetType());
+            _logger = session.SessionLoggerFactory.CreateLogger(GetType());
 
             session.ChannelWindowAdjustReceived += OnChannelWindowAdjust;
             session.ChannelDataReceived += OnChannelData;

src/Renci.SshNet/Channels/ChannelDirectTcpip.cs

@@ -33,7 +33,7 @@ internal sealed class ChannelDirectTcpip : ClientChannel, IChannelDirectTcpip
         public ChannelDirectTcpip(ISession session, uint localChannelNumber, uint localWindowSize, uint localPacketSize)
             : base(session, localChannelNumber, localWindowSize, localPacketSize)
         {
-            _logger = SshNetLoggingConfiguration.LoggerFactory.CreateLogger<ChannelDirectTcpip>();
+            _logger = session.SessionLoggerFactory.CreateLogger<ChannelDirectTcpip>();
         }
 
         /// <summary>

src/Renci.SshNet/Channels/ChannelForwardedTcpip.cs

@@ -48,7 +48,7 @@ internal ChannelForwardedTcpip(ISession session,
                    remoteWindowSize,
                    remotePacketSize)
         {
-            _logger = SshNetLoggingConfiguration.LoggerFactory.CreateLogger<ChannelForwardedTcpip>();
+            _logger = session.SessionLoggerFactory.CreateLogger<ChannelForwardedTcpip>();
         }
 
         /// <summary>

src/Renci.SshNet/Connection/ConnectorBase.cs

@@ -16,12 +16,12 @@ internal abstract class ConnectorBase : IConnector
     {
         private readonly ILogger _logger;
 
-        protected ConnectorBase(ISocketFactory socketFactory)
+        protected ConnectorBase(ISocketFactory socketFactory, ILoggerFactory loggerFactory)
         {
             ThrowHelper.ThrowIfNull(socketFactory);
 
             SocketFactory = socketFactory;
-            _logger = SshNetLoggingConfiguration.LoggerFactory.CreateLogger(GetType());
+            _logger = loggerFactory.CreateLogger(GetType());
         }
 
         internal ISocketFactory SocketFactory { get; private set; }

src/Renci.SshNet/Connection/DirectConnector.cs

@@ -2,12 +2,14 @@
 using System.Net.Sockets;
 using System.Threading;
 
+using Microsoft.Extensions.Logging;
+
 namespace Renci.SshNet.Connection
 {
     internal sealed class DirectConnector : ConnectorBase
     {
-        public DirectConnector(ISocketFactory socketFactory)
-            : base(socketFactory)
+        public DirectConnector(ISocketFactory socketFactory, ILoggerFactory loggerFactory)
+            : base(socketFactory, loggerFactory)
         {
         }
 

src/Renci.SshNet/Connection/HttpConnector.cs

@@ -5,6 +5,8 @@
 using System.Net.Sockets;
 using System.Text.RegularExpressions;
 
+using Microsoft.Extensions.Logging;
+
 using Renci.SshNet.Abstractions;
 using Renci.SshNet.Common;
 
@@ -48,8 +50,8 @@ internal sealed partial class HttpConnector : ProxyConnector
         private static readonly Regex HttpHeaderRegex = new Regex(HttpHeaderPattern, RegexOptions.Compiled);
 #endif
 
-        public HttpConnector(ISocketFactory socketFactory)
-            : base(socketFactory)
+        public HttpConnector(ISocketFactory socketFactory, ILoggerFactory loggerFactory)
+            : base(socketFactory, loggerFactory)
         {
         }
 

src/Renci.SshNet/Connection/ProxyConnector.cs

@@ -4,6 +4,8 @@
 using System.Threading;
 using System.Threading.Tasks;
 
+using Microsoft.Extensions.Logging;
+
 namespace Renci.SshNet.Connection
 {
     /// <summary>
@@ -12,8 +14,8 @@ namespace Renci.SshNet.Connection
     /// </summary>
     internal abstract class ProxyConnector : ConnectorBase
     {
-        protected ProxyConnector(ISocketFactory socketFactory)
-            : base(socketFactory)
+        protected ProxyConnector(ISocketFactory socketFactory, ILoggerFactory loggerFactory)
+            : base(socketFactory, loggerFactory)
         {
         }
 

src/Renci.SshNet/Connection/Socks4Connector.cs

@@ -4,6 +4,8 @@
 using System.Net.Sockets;
 using System.Text;
 
+using Microsoft.Extensions.Logging;
+
 using Renci.SshNet.Abstractions;
 using Renci.SshNet.Common;
 
@@ -17,8 +19,8 @@ namespace Renci.SshNet.Connection
     /// </remarks>
     internal sealed class Socks4Connector : ProxyConnector
     {
-        public Socks4Connector(ISocketFactory socketFactory)
-            : base(socketFactory)
+        public Socks4Connector(ISocketFactory socketFactory, ILoggerFactory loggerFactory)
+            : base(socketFactory, loggerFactory)
         {
         }