Merge pull request #278 from Simon-Campbell/expose-default-fault-tran…

…sformer

Make a default FaultExceptionTransformer

src/SoapCore/DefaultFaultExceptionTransformer.cs

@@ -0,0 +1,35 @@
+using System;
+using System.ServiceModel.Channels;
+
+namespace SoapCore
+{
+	/// <summary>
+	/// The default implementation of the fault provider when an unexpected exception occurs. This can be replaced or
+	/// extended by registering your own IFaultExceptionTransformer in the service collection on startup.
+	/// </summary>
+	public class DefaultFaultExceptionTransformer : IFaultExceptionTransformer
+	{
+		private readonly ExceptionTransformer _exceptionTransformer;
+
+		public DefaultFaultExceptionTransformer()
+		{
+			_exceptionTransformer = null;
+		}
+
+		public DefaultFaultExceptionTransformer(ExceptionTransformer exceptionTransformer)
+		{
+			_exceptionTransformer = exceptionTransformer;
+		}
+
+		public Message ProvideFault(Exception exception, MessageVersion messageVersion)
+		{
+			var bodyWriter = _exceptionTransformer == null ?
+				new FaultBodyWriter(exception, messageVersion) :
+				new FaultBodyWriter(exception, messageVersion, faultStringOverride: _exceptionTransformer.Transform(exception));
+
+			var soapCoreFaultMessage = Message.CreateMessage(messageVersion, null, bodyWriter);
+
+			return new CustomMessage(soapCoreFaultMessage);
+		}
+	}
+}

src/SoapCore/ExceptionTransformer.cs

@@ -1,11 +1,8 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading.Tasks;
+using System;
 
 namespace SoapCore
 {
-	internal class ExceptionTransformer
+	public class ExceptionTransformer
 	{
 		private readonly Func<Exception, string> _transformer;
 

src/SoapCore/SoapEndpointExtensions.cs

@@ -59,6 +59,8 @@ public static IApplicationBuilder UseSoapEndpoint(this IApplicationBuilder build
 		public static IServiceCollection AddSoapCore(this IServiceCollection serviceCollection)
 		{
 			serviceCollection.TryAddSingleton<IOperationInvoker, DefaultOperationInvoker>();
+			serviceCollection.TryAddSingleton<IFaultExceptionTransformer, DefaultFaultExceptionTransformer>();
+
 			return serviceCollection;
 		}
 

src/SoapCore/SoapEndpointMiddleware.cs

@@ -663,25 +663,8 @@ private Message WriteErrorResponseMessage(
 			MessageEncoder messageEncoder,
 			HttpContext httpContext)
 		{
-			Message faultMessage;
-
-			var faultExceptionTransformer = serviceProvider.GetService<IFaultExceptionTransformer>();
-
-			if (faultExceptionTransformer != null)
-			{
-				faultMessage = faultExceptionTransformer.ProvideFault(exception, messageEncoder.MessageVersion);
-			}
-			else
-			{
-				var transformer = serviceProvider.GetService<ExceptionTransformer>();
-
-				var bodyWriter = transformer == null ?
-					new FaultBodyWriter(exception, messageEncoder.MessageVersion) :
-					new FaultBodyWriter(exception, messageEncoder.MessageVersion, faultStringOverride: transformer.Transform(exception));
-
-				var soapCoreFaultMessage = Message.CreateMessage(messageEncoder.MessageVersion, null, bodyWriter);
-				faultMessage = new CustomMessage(soapCoreFaultMessage);
-			}
+			var faultExceptionTransformer = serviceProvider.GetRequiredService<IFaultExceptionTransformer>();
+			var faultMessage = faultExceptionTransformer.ProvideFault(exception, messageEncoder.MessageVersion);
 
 			httpContext.Response.ContentType = httpContext.Request.ContentType;
 			httpContext.Response.Headers["SOAPAction"] = faultMessage.Headers.Action;