#1 | ADDED: Transmitter concept for hooking Sending Function.

TitanShark.Thresher.Core.Tests/InMemoryRecorderTests.cs

@@ -22,7 +22,7 @@ public async Task InMemoryRecorder_Works_WithSingleCall()
             // prepares
             var persistence = new InMemoryRecordsPersistence();
             var recorder = new Recorder(persistence);
-            var handler = new SerialInterceptionHttpClientHandler(recorder);
+            var handler = new SerialInterceptionHttpClientHandler(interceptors: recorder);
             var sut = new HttpClient(handler);
 
             // acts
@@ -48,7 +48,7 @@ public async Task InMemoryRecorder_Works_WithMultipleCalls()
             // prepares
             var persistence = new InMemoryRecordsPersistence();
             var recorder = new Recorder(persistence);
-            var handler = new SerialInterceptionHttpClientHandler(recorder);
+            var handler = new SerialInterceptionHttpClientHandler(interceptors: recorder);
             var sut = new HttpClient(handler);
 
             const int numberOfCalls = 100;

TitanShark.Thresher.Core.Tests/TransmitterTests.cs

@@ -0,0 +1,47 @@
+using FluentAssertions;
+using System.Net.Http;
+using System.Threading.Tasks;
+using Xunit;
+using Xunit.Abstractions;
+
+namespace TitanShark.Thresher.Core.Tests
+{
+    public class TransmitterTests
+    {
+        private readonly ITestOutputHelper _output;
+
+        public TransmitterTests(ITestOutputHelper output)
+        {
+            _output = output;
+        }
+
+        [Fact]
+        public async Task Custom_SendFunction_In_Transmitter_Is_Possible()
+        {
+            // prepares
+            const string responseContentText = "Hello World!";
+            var transmitter = new Transmitter
+                (
+                    (callId, request, cancellationToken) =>
+                    {
+                        _output.WriteLine($"Request to '{request.RequestUri}' was sent out.");
+
+                        return Task.FromResult(new HttpResponseMessage(System.Net.HttpStatusCode.Created) 
+                        { 
+                            Content = new StringContent(responseContentText) 
+                        });
+                    }
+                );
+            var handler = new SerialInterceptionHttpClientHandler(transmitter: transmitter);
+            var sut = new HttpClient(handler);
+
+            // acts
+            var response = await sut.GetAsync("https://testing.only").ConfigureAwait(false);
+            var content = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
+
+            // asserts
+            response.StatusCode.Should().Be(System.Net.HttpStatusCode.Created);
+            content.Should().Be(responseContentText);
+        }
+    }
+}

TitanShark.Thresher.Core/InterceptableHttpClientHandler.cs

@@ -10,10 +10,14 @@ public abstract class InterceptableHttpClientHandler : HttpClientHandler
     {
         internal IList<IInterceptor> Interceptors { get; } = new List<IInterceptor>();
 
+        internal Transmitter Transmitter { get; }
+
         public bool HasAnyInterceptor => Interceptors != null && Interceptors.Count > 0;
 
-        protected InterceptableHttpClientHandler(params IInterceptor[] interceptors)
+        protected InterceptableHttpClientHandler(Transmitter transmitter = null, params IInterceptor[] interceptors)
         {
+            Transmitter = transmitter ?? CreateDefaultTransmitter();
+
             if (interceptors != null && interceptors.Length > 0)
             {
                 foreach(var interceptor in interceptors) 
@@ -45,9 +49,24 @@ protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage
             }
         }
 
+        protected virtual Transmitter CreateDefaultTransmitter()
+        {
+            return new Transmitter
+            (
+                (callId, request, cancellationToken) => base.SendAsync(request, cancellationToken)
+            );
+        }
+
         protected virtual Task<HttpResponseMessage> OnSending(CallId callId, HttpRequestMessage request, CancellationToken cancellationToken)
         {
-            return base.SendAsync(request, cancellationToken);
+            var sendFunction = Transmitter?.SendFunction;
+
+            if (sendFunction != null)
+            {
+                return sendFunction(callId, request, cancellationToken);
+            }
+
+            return Task.FromResult(default(HttpResponseMessage));
         }
 
         protected abstract Task OnPreparing(CallId callId, HttpRequestMessage request, CancellationToken cancellationToken);

TitanShark.Thresher.Core/SerialInterceptionHttpClientHandler.cs

@@ -8,7 +8,7 @@ namespace TitanShark.Thresher.Core
 {
     public class SerialInterceptionHttpClientHandler : InterceptableHttpClientHandler
     {
-        public SerialInterceptionHttpClientHandler(params IInterceptor[] interceptors) : base(interceptors)
+        public SerialInterceptionHttpClientHandler(Transmitter transmitter = null, params IInterceptor[] interceptors) : base(transmitter, interceptors)
         {
         }
 

TitanShark.Thresher.Core/_Fundamentals/Transmitter.cs

@@ -0,0 +1,22 @@
+using System;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace TitanShark.Thresher.Core
+{
+    public class Transmitter
+    {
+        public Func<CallId, HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> SendFunction { get; }
+
+        public Transmitter(Func<CallId, HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> sendFunction)
+        {
+            if (sendFunction == null)
+            {
+                throw new ArgumentNullException(nameof(sendFunction));
+            }
+
+            SendFunction = sendFunction;
+        }
+    }
+}