rebus-org#1154 Error handler not having access to the original except…

…ions - DefaultRetryStep using ExceptionInfo factory to create ExceptionInfo instead of newing it up; when configuring Rebus with InMemExceptionInfoFactory [Configure.With(activator).Errors(e => e.UseInMemExceptionInfos())],

an error handler will get an instance of InMemExceptionInfo in HandlePoisonMessage method, with InMemExceptionInfo storing all exceptions within AggregateException; not tested - tests will be added in a subsequent commit when this approach is approved

Rebus/Retry/IExceptionInfoFactory.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 
 namespace Rebus.Retry;
 
@@ -13,4 +14,13 @@ public interface IExceptionInfoFactory
     /// <param name="exception">Source exception.</param>
     /// <returns>An <see cref="ExceptionInfo"/> containing information from the supplied exception.</returns>
     ExceptionInfo CreateInfo(Exception exception);
+
+    /// <summary>
+    /// Create an <see cref="ExceptionInfo"/> from a collection of exception infos.
+    /// </summary>
+    /// <param name="exceptionInfos">Collection of exception infos</param>
+    /// <param name="message">Message</param>
+    /// <param name="details">Details</param>
+    /// <returns></returns>
+    ExceptionInfo CreateInfo(IEnumerable<ExceptionInfo> exceptionInfos, string message, string details);
 }

Rebus/Retry/Info/InMemExceptionInfo.cs

@@ -1,5 +1,7 @@
 using Rebus.Extensions;
 using System;
+using System.Collections.Generic;
+using System.Linq;
 
 namespace Rebus.Retry.Info;
 
@@ -21,6 +23,21 @@ public InMemExceptionInfo(Exception exception) : base(
         Exception = exception ?? throw new ArgumentNullException(nameof(exception));
     }
 
+    /// <summary>
+    /// Constructs a new in-memory exception info from a collection of exception infos, with an option to override the message and details.
+    /// </summary>
+    /// <param name="exceptionInfos">Collection of exception infos</param>
+    /// <param name="Message">Message</param>
+    /// <param name="Details">Details</param>
+    public InMemExceptionInfo(IEnumerable<ExceptionInfo> exceptionInfos, string Message, string Details) : base(
+        typeof(AggregateException).GetSimpleAssemblyQualifiedName(),
+        Message,
+        Details,
+        DateTimeOffset.Now)
+    {
+        Exception = new AggregateException(exceptionInfos.OfType<InMemExceptionInfo>().Select(x => x.Exception));
+    }
+
     /// <summary>
     /// Gets or sets the original exception.
     /// </summary>

Rebus/Retry/Info/InMemExceptionInfoFactory.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 
 namespace Rebus.Retry.Info;
 
@@ -17,4 +18,16 @@ public class InMemExceptionInfoFactory : IExceptionInfoFactory
     /// <param name="exception">Source exception.</param>
     /// <returns>An <see cref="ExceptionInfo"/> containing information from the supplied exception.</returns>
     public ExceptionInfo CreateInfo(Exception exception) => new InMemExceptionInfo(exception);
+
+    /// <summary>
+    /// Create an <see cref="ExceptionInfo"/> from a collection of exception infos and store the original exceptions.
+    /// </summary>
+    /// <param name="exceptionInfos">Collection of exception infos</param>
+    /// <param name="message">Message</param>
+    /// <param name="details">Details</param>
+    /// <returns></returns>
+    public ExceptionInfo CreateInfo(IEnumerable<ExceptionInfo> exceptionInfos, string message, string details)
+    {
+        return new InMemExceptionInfo(exceptionInfos, message, details);
+    }
 }

Rebus/Retry/Info/ToStringExceptionInfoFactory.cs

@@ -1,4 +1,6 @@
 using System;
+using System.Collections.Generic;
+using Rebus.Extensions;
 
 namespace Rebus.Retry.Info;
 
@@ -13,4 +15,21 @@ public class ToStringExceptionInfoFactory : IExceptionInfoFactory
     /// <param name="exception">Source exception.</param>
     /// <returns>An <see cref="ExceptionInfo"/> containing information from the supplied exception.</returns>
     public ExceptionInfo CreateInfo(Exception exception) => ExceptionInfo.FromException(exception);
+
+    /// <summary>
+    /// Create an <see cref="ExceptionInfo"/> from a collection of exception infos.
+    /// </summary>
+    /// <param name="exceptionInfos">Collection of exception infos</param>
+    /// <param name="message">Message</param>
+    /// <param name="details">Details</param>
+    /// <returns></returns>
+    public ExceptionInfo CreateInfo(IEnumerable<ExceptionInfo> exceptionInfos, string message, string details)
+    {
+        return new ExceptionInfo(
+            Type: typeof(AggregateException).GetSimpleAssemblyQualifiedName(),
+            Message: message,
+            Details: details,
+            Time: DateTimeOffset.Now
+        );
+    }
 }

Rebus/Retry/Simple/DefaultRetryStep.cs

@@ -206,14 +206,13 @@ async Task PassToErrorHandler(StepContext context, ExceptionInfo exception)
         await scope.CompleteAsync();
     }
 
-    static ExceptionInfo GetAggregateException(IEnumerable<ExceptionInfo> exceptions)
+    ExceptionInfo GetAggregateException(IEnumerable<ExceptionInfo> exceptions)
     {
         var list = exceptions.ToList();
 
-        return new(typeof(AggregateException).GetSimpleAssemblyQualifiedName(),
+        return _exceptionInfoFactory.CreateInfo(list,
             $"{list.Count} unhandled exceptions",
-            string.Join(Environment.NewLine + Environment.NewLine, list.Select(e => e.GetFullErrorDescription())),
-            DateTimeOffset.Now
+            string.Join(Environment.NewLine + Environment.NewLine, list.Select(e => e.GetFullErrorDescription()))
         );
     }
 }