Exception serialization support for built-in messages (akkadotnet#6297

)

* added end to end spec to validate error serialization for remote actor supervision

* defined `.proto`s for `Status.Failure` and `Status.Success`

* added `Status.,Failure` and `Status.Success` support to the `MiscMessageSerializer`

* added tests to `MiscMessageSerializerSpec`

* close akkadotnet#3903

src/core/Akka.Remote.Tests/Serialization/Bugfix3903Spec.cs

@@ -0,0 +1,124 @@
+//-----------------------------------------------------------------------
+// <copyright file="Bugfix3903Specs.cs" company="Akka.NET Project">
+//     Copyright (C) 2009-2022 Lightbend Inc. <http://www.lightbend.com>
+//     Copyright (C) 2013-2022 .NET Foundation <https://github.com/akkadotnet/akka.net>
+// </copyright>
+//-----------------------------------------------------------------------
+
+using System;
+using System.Threading.Tasks;
+using Akka.Actor;
+using Akka.Configuration;
+using Akka.TestKit;
+using Akka.Util.Internal;
+using Xunit;
+using Xunit.Abstractions;
+using FluentAssertions;
+
+namespace Akka.Remote.Tests.Serialization
+{
+    public class Bugfix3903Spec : AkkaSpec
+    {
+        // hocon config enabling akka.remote
+        private static readonly Config Config = @"akka.actor.provider = remote
+                                                    akka.remote.dot-netty.tcp.hostname = localhost
+                                                    akka.remote.dot-netty.tcp.port = 0";
+
+        public Bugfix3903Spec(ITestOutputHelper outputHelper) : base(Config, outputHelper)
+        {
+        }
+
+        #region Internal Types
+
+        // parent actor type that will remotely deploy a child actor type onto a specific address
+        private class ParentActor : ReceiveActor
+        {
+            // message type that includes an Address
+            public class DeployChild
+            {
+                public DeployChild(Address address)
+                {
+                    Address = address;
+                }
+
+                public Address Address { get; }
+            }
+
+            public ParentActor()
+            {
+                Receive<DeployChild>(s =>
+                {
+                    // props to deploy an EchoActor at the address specified in DeployChild
+                    var props = Props.Create<EchoActor>().WithDeploy(new Deploy(new RemoteScope(s.Address)));
+                    var child = Context.ActorOf(props, "child");
+                    Sender.Tell(child);
+                });
+            }
+        }
+
+        internal class EchoActor : ReceiveActor
+        {
+            public class Fail
+            {
+                public static readonly Fail Instance = new Fail();
+                private Fail(){}
+            }
+
+            public EchoActor()
+            {
+                // receive message that will cause this actor to fail
+                Receive<Fail>(s =>
+                {
+                    throw new ApplicationException("fail");
+                });
+                ReceiveAny(o => Sender.Tell(o));
+            }
+        }
+
+        #endregion
+
+        // a test where Sys starts a ParentActor and has it remotely deploy an EchoActor onto a second ActorSystem
+        [Fact]
+        public async Task ParentActor_should_be_able_to_deploy_EchoActor_to_remote_system()
+        {
+            // create a second ActorSystem
+            var system2 = ActorSystem.Create(Sys.Name, Sys.Settings.Config);
+            InitializeLogger(system2);
+            try
+            {
+                // create a supervision strategy that will send a message to the TestActor including the exception of the child that failed
+                var strategy = new OneForOneStrategy(ex =>
+                {
+                    TestActor.Tell(ex);
+                    return Directive.Stop;
+                });
+
+                // create a ParentActor in the first ActorSystem
+                var parent = Sys.ActorOf(Props.Create<ParentActor>().WithSupervisorStrategy(strategy), "parent");
+
+                // have the ParentActor remotely deploy an EchoActor onto the second ActorSystem
+                var child = await parent
+                    .Ask<IActorRef>(new ParentActor.DeployChild(
+                        system2.AsInstanceOf<ExtendedActorSystem>().Provider.DefaultAddress), RemainingOrDefault).ConfigureAwait(false);
+
+                // assert that Child is a remote actor reference
+                child.Should().BeOfType<RemoteActorRef>();
+                Watch(child);
+
+                // send a message to the EchoActor and verify that it is received
+                (await child.Ask<string>("hello", RemainingOrDefault).ConfigureAwait(false)).Should().Be("hello");
+
+                // cause the child to crash
+                child.Tell(EchoActor.Fail.Instance);
+                var exception = ExpectMsg<ApplicationException>();
+                exception.Message.Should().Be("fail");
+                ExpectTerminated(child);
+            }
+            finally
+            {
+                // shut down the second ActorSystem
+                Shutdown(system2);
+            }
+        }
+    }
+}

src/core/Akka.Remote.Tests/Serialization/MiscMessageSerializerSpec.cs

@@ -76,6 +76,30 @@ public void Can_serialize_IdentifyWithNull()
             AssertEqual(identify);
         }
 
+        [Theory]
+        [InlineData(null)]
+        [InlineData(1)]
+        [InlineData("hi")]
+        public void Can_serialize_StatusSuccess(object payload)
+        {
+            var success = new Status.Success(payload);
+            AssertEqual(success);
+        }
+
+        [Theory]
+        [InlineData(null)]
+        [InlineData(1)]
+        [InlineData("hi")]
+        public void Can_serialize_StatusFailure(object payload)
+        {
+            var success = new Status.Failure(new ApplicationException("foo"),payload);
+            // can't use AssertEqual here since the Exception data isn't 100% identical after round-trip serialization
+            var deserialized = AssertAndReturn(success);
+            deserialized.State.Should().BeEquivalentTo(success.State);
+            deserialized.Cause.Message.Should().BeEquivalentTo(success.Cause.Message);
+            deserialized.Cause.Should().BeOfType(success.Cause.GetType());
+        }
+
         [Fact]
         public void Can_serialize_ActorIdentity()
         {
@@ -372,7 +396,7 @@ private T AssertAndReturn<T>(T message)
         private void AssertEqual<T>(T message)
         {
             var deserialized = AssertAndReturn(message);
-            Assert.Equal(message, deserialized);
+            deserialized.Should().BeEquivalentTo(message);
         }
     }
 }

src/core/Akka.Remote/Configuration/Remote.conf

@@ -39,6 +39,8 @@ akka {
       "Akka.Actor.PoisonPill, Akka" = akka-misc
       "Akka.Actor.Kill, Akka" = akka-misc
       "Akka.Actor.PoisonPill, Akka" = akka-misc
+      "Akka.Actor.Status+Failure, Akka" = akka-misc
+      "Akka.Actor.Status+Success, Akka" = akka-misc
       #"Akka.Actor.LocalScope, Akka" = akka-misc
       "Akka.Actor.RemoteScope, Akka" = akka-misc
       "Akka.Routing.FromConfig, Akka" = akka-misc

src/core/Akka.Remote/Serialization/ExceptionSupport.cs

@@ -150,7 +150,7 @@ public Exception ExceptionFromProtoNet(Proto.Msg.ExceptionData proto)
             return obj;
         }
 
-        private string ValueOrNull(string value)
+        private static string ValueOrNull(string value)
             => string.IsNullOrEmpty(value) ? null : value;
     }
 }

src/core/Akka.Remote/Serialization/MessageContainerSerializer.cs

@@ -9,7 +9,6 @@
 using System.Linq;
 using System.Runtime.Serialization;
 using Akka.Actor;
-using Akka.Remote.Serialization.Proto.Msg;
 using Akka.Serialization;
 using Akka.Util;
 using Google.Protobuf;
@@ -108,7 +107,7 @@ public override object FromBinary(byte[] bytes, Type type)
             return new ActorSelectionMessage(message, elements);
         }
 
-        private Proto.Msg.Selection BuildPattern(string matcher, Proto.Msg.Selection.Types.PatternType tpe)
+        private static Proto.Msg.Selection BuildPattern(string matcher, Proto.Msg.Selection.Types.PatternType tpe)
         {
             var selection = new Proto.Msg.Selection { Type = tpe };
             if (matcher != null)