Fixed #30 Test if new Tapeti async consumer runs parallel

Alternative fix for #29 Deserialization errors due to not buffering RabbitMQ Client's body

07-ParallelizationTest/07-ParallelizationTest.csproj

@@ -0,0 +1,20 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+    <RootNamespace>_07_ParallelizationTest</RootNamespace>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="SimpleInjector" Version="5.3.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\Examples\ExampleLib\ExampleLib.csproj" />
+    <ProjectReference Include="..\Examples\Messaging.TapetiExample\Messaging.TapetiExample.csproj" />
+    <ProjectReference Include="..\Tapeti.SimpleInjector\Tapeti.SimpleInjector.csproj" />
+    <ProjectReference Include="..\Tapeti\Tapeti.csproj" />
+  </ItemGroup>
+
+</Project>

07-ParallelizationTest/IMessageParallelization.cs

@@ -0,0 +1,9 @@
+using System.Threading.Tasks;
+
+namespace _07_ParallelizationTest
+{
+    public interface IMessageParallelization
+    {
+        Task WaitForBatch();
+    }
+}

07-ParallelizationTest/ParallelizationMessageController.cs

@@ -0,0 +1,24 @@
+using System.Threading.Tasks;
+using Messaging.TapetiExample;
+using Tapeti.Annotations;
+
+namespace _07_ParallelizationTest
+{
+    [MessageController]
+    [DynamicQueue("tapeti.example.07")]
+    public class ParallelizationMessageController
+    {
+        private readonly IMessageParallelization messageParallelization;
+
+        public ParallelizationMessageController(IMessageParallelization messageParallelization)
+        {
+            this.messageParallelization = messageParallelization;
+        }
+
+
+        public async Task HandleSpeedTestMessage(SpeedTestMessage message)
+        {
+            await messageParallelization.WaitForBatch();
+        }
+    }
+}

07-ParallelizationTest/Program.cs

@@ -0,0 +1,148 @@
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using ExampleLib;
+using Messaging.TapetiExample;
+using SimpleInjector;
+using Tapeti;
+using Tapeti.Default;
+using Tapeti.SimpleInjector;
+
+namespace _07_ParallelizationTest
+{
+    public class Program
+    {
+        private const int MessageCount = 3000;
+        private const int RepeatBatch = 4;
+
+
+        public static void Main()
+        {
+            var container = new Container();
+            var dependencyResolver = new SimpleInjectorDependencyResolver(container);
+
+            container.Register<ILogger, ConsoleLogger>();
+
+            var helper = new ExampleConsoleApp(dependencyResolver);
+            helper.Run(MainAsync);
+        }
+
+
+        internal static async Task MainAsync(IDependencyResolver dependencyResolver, Func<Task> waitForDone)
+        {
+            var doneCount = 0;
+            
+            var container = (IDependencyContainer) dependencyResolver;
+            container.RegisterDefaultSingleton<IMessageParallelization>(new MessageParallelization(MessageCount, () =>
+            {
+                doneCount++;
+                Console.WriteLine($"Processed batch #{doneCount}");
+                
+                if (doneCount != RepeatBatch) 
+                    return false;
+                
+                var exampleState = dependencyResolver.Resolve<IExampleState>();
+                exampleState.Done();
+                return true;
+            }, count =>
+            {
+                Console.WriteLine($"Timeout while processing batch after processing {count} messages");
+                
+                var exampleState = dependencyResolver.Resolve<IExampleState>();
+                exampleState.Done();
+            }));
+
+
+
+            var config = new TapetiConfig(dependencyResolver)
+                .RegisterAllControllers()
+                .Build();
+
+
+            await using var connection = new TapetiConnection(config)
+            {
+                Params = new TapetiConnectionParams
+                {
+                    // Default is 50, which means we'll get a timeout after 50 messages
+                    PrefetchCount = MessageCount
+                }
+            };
+            
+            var subscriber = await connection.Subscribe(false);
+
+
+            var publisher = dependencyResolver.Resolve<IPublisher>();
+            Console.WriteLine($"Publishing {MessageCount * RepeatBatch} messages...");
+
+            await PublishMessages(publisher, MessageCount * RepeatBatch);
+
+
+
+            Console.WriteLine("Consuming messages...");
+            await subscriber.Resume();
+            await waitForDone();
+        }
+
+
+        internal static async Task PublishMessages(IPublisher publisher, int messageCount)
+        {
+            for (var i = 0; i < messageCount; i++)
+            {
+                await publisher.Publish(new SpeedTestMessage
+                {
+                    PublishCount = i
+                });
+            }
+        }
+    }
+
+
+    internal class MessageParallelization : IMessageParallelization
+    {
+        private readonly int max;
+        private readonly Func<bool> done;
+        private readonly Action<int> timeout;
+        private int count;
+        private readonly object waitLock = new object();
+        private TaskCompletionSource<bool> batchReachedTask = new TaskCompletionSource<bool>();
+        private Timer messageExpectedTimer;
+        private readonly TimeSpan messageExpectedTimeout = TimeSpan.FromMilliseconds(5000);
+
+
+        public MessageParallelization(int max, Func<bool> done, Action<int> timeout)
+        {
+            this.max = max;
+            this.done = done;
+            this.timeout = timeout;
+        }
+
+
+        public Task WaitForBatch()
+        {
+            lock (waitLock)
+            {
+                if (messageExpectedTimer == null)
+                    messageExpectedTimer = new Timer(state =>
+                    {
+                        timeout(count);
+                    }, null, messageExpectedTimeout, Timeout.InfiniteTimeSpan);
+                else
+                    messageExpectedTimer.Change(messageExpectedTimeout, Timeout.InfiniteTimeSpan);
+
+                count++;
+                if (count != max)
+                    return batchReachedTask.Task;
+
+                if (done())
+                    messageExpectedTimer.Dispose();
+                    
+                count = 0;
+
+                batchReachedTask.SetResult(true);
+                batchReachedTask = new TaskCompletionSource<bool>();
+
+                return Task.CompletedTask;
+            }
+        }
+    }
+}

Tapeti.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio 15
+# Visual Studio Version 16
-VisualStudioVersion = 15.0.27703.2026
+VisualStudioVersion = 16.0.31005.135
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Tapeti.Annotations", "Tapeti.Annotations\Tapeti.Annotations.csproj", "{4B742AB2-59DD-4792-8E0F-D80B5366B844}"
 EndProject
@@ -57,7 +57,9 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Tools", "Tools", "{62002327
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Tapeti.Cmd", "Tapeti.Cmd\Tapeti.Cmd.csproj", "{C8728BFC-7F97-41BC-956B-690A57B634EC}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "06-StatelessRequestResponse", "Examples\06-StatelessRequestResponse\06-StatelessRequestResponse.csproj", "{152227AA-3165-4550-8997-6EA80C84516E}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "06-StatelessRequestResponse", "Examples\06-StatelessRequestResponse\06-StatelessRequestResponse.csproj", "{152227AA-3165-4550-8997-6EA80C84516E}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "07-ParallelizationTest", "07-ParallelizationTest\07-ParallelizationTest.csproj", "{E69E6BA5-68E7-4A4D-A38C-B2526AA66E96}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -157,6 +159,10 @@ Global
 		{152227AA-3165-4550-8997-6EA80C84516E}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{152227AA-3165-4550-8997-6EA80C84516E}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{152227AA-3165-4550-8997-6EA80C84516E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{E69E6BA5-68E7-4A4D-A38C-B2526AA66E96}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{E69E6BA5-68E7-4A4D-A38C-B2526AA66E96}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{E69E6BA5-68E7-4A4D-A38C-B2526AA66E96}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{E69E6BA5-68E7-4A4D-A38C-B2526AA66E96}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -184,6 +190,7 @@ Global
 		{29478B10-FC53-4E93-ADEF-A775D9408131} = {99380F97-AD1A-459F-8AB3-D404E1E6AD4F}
 		{C8728BFC-7F97-41BC-956B-690A57B634EC} = {62002327-46B0-4B72-B95A-594CE7F8C80D}
 		{152227AA-3165-4550-8997-6EA80C84516E} = {266B9B94-A4D2-41C2-860C-24A7C3B63B56}
+		{E69E6BA5-68E7-4A4D-A38C-B2526AA66E96} = {266B9B94-A4D2-41C2-860C-24A7C3B63B56}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {B09CC2BF-B2AF-4CB6-8728-5D1D8E5C50FA}

Tapeti/Connection/TapetiBasicConsumer.cs

@@ -32,11 +32,19 @@ namespace Tapeti.Connection
             IBasicProperties properties,
             ReadOnlyMemory<byte> body)
         {
+            // RabbitMQ.Client 6+ re-uses the body memory. Unfortunately Newtonsoft.Json does not support deserializing
+            // from Span/ReadOnlyMemory yet so we still need to use ToArray and allocate heap memory for it. When support
+            // is implemented we need to rethink the way the body is passed around and maybe deserialize it sooner
+            // (which changes exception handling, which is now done in TapetiConsumer exclusively).
+            //
+            // See also: https://github.com/JamesNK/Newtonsoft.Json/issues/1761
+            var bodyArray = body.ToArray();
+            
             Task.Run(async () =>
             {
                 try
                 {
-                    var response = await consumer.Consume(exchange, routingKey, new RabbitMQMessageProperties(properties), body.ToArray());
+                    var response = await consumer.Consume(exchange, routingKey, new RabbitMQMessageProperties(properties), bodyArray);
                     await onRespond(deliveryTag, response);
                 }
                 catch