The message handler gets passed to the Start method

Putting it in the constructor didn't make sense, because some message handlers may not be usable with DI.

Author: fubar-coder

README.md

@@ -14,12 +14,13 @@ The following example creates a PAM transaction and tries to authenticate a user
 // Create the service
 var pamService = new PamService(
     // The service options
-    new OptionsWrapper<PamSessionConfiguration>(new PamSessionConfiguration()),
-    // The PAM message handler
-    new ConsoleMessageHandler());
+    new OptionsWrapper<PamSessionConfiguration>(new PamSessionConfiguration()));
+
+// The PAM message handler
+var messageHandler = new ConsoleMessageHandler();
 
 // Create a PAM transaction
-using (var pamTransaction = pamService.Start())
+using (var pamTransaction = pamService.Start(messageHandler))
 {
     // Change the user prompt
     pamTransaction.UserPrompt = "my customized user login prompt: ";

samples/LoginSharp/Program.cs

@@ -57,7 +57,8 @@ private static void ExecuteLogin()
             while (true)
             {
                 var service = services.GetRequiredService<IPamService>();
-                using var transaction = service.Start();
+                var messageHandler = services.GetRequiredService<IPamMessageHandler>();
+                using var transaction = service.Start(messageHandler);
                 transaction.UserPrompt = $"{hostName} login: ";
                 transaction.UserName = null;
 

src/FubarDev.PamSharp/IPamService.cs

@@ -12,8 +12,11 @@ public interface IPamService
         /// <summary>
         /// Initializes a PAM transaction.
         /// </summary>
+        /// <param name="messageHandler">The message handler.</param>
         /// <param name="user">The user name.</param>
         /// <returns>The new PAM transaction.</returns>
-        IPamTransaction Start(string? user = null);
+        IPamTransaction Start(
+            IPamMessageHandler messageHandler,
+            string? user = null);
     }
 }

src/FubarDev.PamSharp/PamService.cs

@@ -17,8 +17,6 @@ namespace FubarDev.PamSharp
     /// </summary>
     public class PamService : IPamService
     {
-        private readonly IPamMessageHandler _messageHandler;
-
         private readonly ILogger<PamService>? _logger;
 
         private readonly PamSessionConfiguration _configuration;
@@ -27,23 +25,22 @@ public class PamService : IPamService
         /// Initializes a new instance of the <see cref="PamService"/> class.
         /// </summary>
         /// <param name="options">The options for the PAM service.</param>
-        /// <param name="messageHandler">The message handler.</param>
         /// <param name="logger">The logger.</param>
         public PamService(
             IOptions<PamSessionConfiguration> options,
-            IPamMessageHandler messageHandler,
             ILogger<PamService>? logger = null)
         {
-            _messageHandler = messageHandler;
             _logger = logger;
             _configuration = options.Value;
         }
 
         /// <inheritdoc/>
-        public IPamTransaction Start(string? user = null)
+        public IPamTransaction Start(
+            IPamMessageHandler messageHandler,
+            string? user = null)
         {
-            var conversationHandler = _configuration.CreateMessaging?.Invoke(_messageHandler)
-                ?? new PamConversationHandler(_messageHandler);
+            var conversationHandler = _configuration.CreateMessaging?.Invoke(messageHandler)
+                ?? new PamConversationHandler(messageHandler);
 
             PamStatus ConversationCallback(int messageCount, IntPtr messages, out IntPtr responseArrayPtr, IntPtr appDataPtr)
             {

test/FubarDev.PamSharp.Tests/PamTransactionTests.cs

@@ -27,8 +27,9 @@ public void CanRequestTransaction()
             IPamTransaction pamTransaction;
             using (var scope = _serviceProvider.CreateScope())
             {
+                var messageHandler = scope.ServiceProvider.GetRequiredService<IPamMessageHandler>();
                 var service = scope.ServiceProvider.GetRequiredService<IPamService>();
-                pamTransaction = service.Start();
+                pamTransaction = service.Start(messageHandler);
             }
 
             Assert.NotEqual(IntPtr.Zero, pamTransaction.Handle);
@@ -43,8 +44,9 @@ public void CanStartAndStopTransaction()
         {
             using (var scope = _serviceProvider.CreateScope())
             {
+                var messageHandler = scope.ServiceProvider.GetRequiredService<IPamMessageHandler>();
                 var service = scope.ServiceProvider.GetRequiredService<IPamService>();
-                using (service.Start())
+                using (service.Start(messageHandler))
                 {
                     // Do nothing
                 }