Change the base class of PrimitiveSerializers to SerializerWithString…

…Manifest (akkadotnet#4989)

* Change the base class of PrimitiveSerializers to SerializerWithStringManifest

* Add backward compatibility to the wire format

* Update API Approver list

src/core/Akka.API.Tests/CoreAPISpec.ApproveRemote.approved.txt

@@ -434,11 +434,11 @@ namespace Akka.Remote.Serialization
         public override string Manifest(object obj) { }
         public override byte[] ToBinary(object obj) { }
     }
-    public sealed class PrimitiveSerializers : Akka.Serialization.Serializer
+    public sealed class PrimitiveSerializers : Akka.Serialization.SerializerWithStringManifest
     {
         public PrimitiveSerializers(Akka.Actor.ExtendedActorSystem system) { }
-        public override bool IncludeManifest { get; }
-        public override object FromBinary(byte[] bytes, System.Type type) { }
+        public override object FromBinary(byte[] bytes, string manifest) { }
+        public override string Manifest(object obj) { }
         public override byte[] ToBinary(object obj) { }
     }
     public class ProtobufSerializer : Akka.Serialization.Serializer

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

@@ -8,6 +8,7 @@
 using Akka.Configuration;
 using Akka.Remote.Configuration;
 using Akka.Remote.Serialization;
+using Akka.Serialization;
 using Akka.TestKit;
 using FluentAssertions;
 using Xunit;
@@ -57,16 +58,29 @@ public void Can_serialize_String(string value)
 
         private T AssertAndReturn<T>(T message)
         {
-            var serializer = Sys.Serialization.FindSerializerFor(message);
+            var serializer = (SerializerWithStringManifest)Sys.Serialization.FindSerializerFor(message);
             serializer.Should().BeOfType<PrimitiveSerializers>();
             var serializedBytes = serializer.ToBinary(message);
-            return (T)serializer.FromBinary(serializedBytes, typeof(T));
+            var manifest = serializer.Manifest(message);
+            return (T)serializer.FromBinary(serializedBytes, manifest);
+        }
+
+        private T AssertCrossPlatformAndReturn<T>(T message)
+        {
+            var serializer = (SerializerWithStringManifest)Sys.Serialization.FindSerializerFor(message);
+            serializer.Should().BeOfType<PrimitiveSerializers>();
+            var serializedBytes = serializer.ToBinary(message);
+            // GetType() will make sure that each namespace is compatible with the serializer
+            // as the test is run on each platform.
+            return (T)serializer.FromBinary(serializedBytes, message.GetType());
         }
 
         private void AssertEqual<T>(T message)
         {
             var deserialized = AssertAndReturn(message);
             Assert.Equal(message, deserialized);
+            deserialized = AssertCrossPlatformAndReturn(message);
+            Assert.Equal(message, deserialized);
         }
     }
 }

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

@@ -13,8 +13,22 @@
 
 namespace Akka.Remote.Serialization
 {
-    public sealed class PrimitiveSerializers : Serializer
+    public sealed class PrimitiveSerializers : SerializerWithStringManifest
     {
+        internal const string StringManifest = "S";
+        internal const string Int32Manifest = "I";
+        internal const string Int64Manifest = "L";
+
+        // .Net Core manifests
+        internal const string StringManifestNetCore = "System.String, System.Private.CoreLib";
+        internal const string Int32ManifestNetCore = "System.Int32, System.Private.CoreLib";
+        internal const string Int64ManifestNetCore = "System.Int64, System.Private.CoreLib";
+
+        // .Net Framework manifests
+        internal const string StringManifestNetFx = "System.String, mscorlib";
+        internal const string Int32ManifestNetFx = "System.Int32, mscorlib";
+        internal const string Int64ManifestNetFx = "System.Int64, mscorlib";
+
         /// <summary>
         /// Initializes a new instance of the <see cref="PrimitiveSerializers" /> class.
         /// </summary>
@@ -23,28 +37,58 @@ public PrimitiveSerializers(ExtendedActorSystem system) : base(system)
         {
         }
 
-        /// <inheritdoc />
-        public override bool IncludeManifest { get; } = true;
-
         /// <inheritdoc />
         public override byte[] ToBinary(object obj)
         {
-            var str = obj as string;
-            if (str != null) return Encoding.UTF8.GetBytes(str);
-            if (obj is int) return BitConverter.GetBytes((int)obj);
-            if (obj is long) return BitConverter.GetBytes((long)obj);
-
-            throw new ArgumentException($"Cannot serialize object of type [{obj.GetType().TypeQualifiedName()}]");
+            switch (obj)
+            {
+                case string s:
+                    return Encoding.UTF8.GetBytes(s);
+                case int i:
+                    return BitConverter.GetBytes(i);
+                case long l:
+                    return BitConverter.GetBytes(l);
+                default:
+                    throw new ArgumentException($"Cannot serialize object of type [{obj.GetType()}]");
+            }
         }
 
         /// <inheritdoc />
-        public override object FromBinary(byte[] bytes, Type type)
+        public override object FromBinary(byte[] bytes, string manifest)
         {
-            if (type == typeof(string)) return Encoding.UTF8.GetString(bytes);
-            if (type == typeof(int)) return BitConverter.ToInt32(bytes, 0);
-            if (type == typeof(long)) return BitConverter.ToInt64(bytes, 0);
+            switch (manifest)
+            {
+                case StringManifest:
+                case StringManifestNetCore:
+                case StringManifestNetFx:
+                    return Encoding.UTF8.GetString(bytes);
+                case Int32Manifest:
+                case Int32ManifestNetCore:
+                case Int32ManifestNetFx:
+                    return BitConverter.ToInt32(bytes, 0);
+                case Int64Manifest:
+                case Int64ManifestNetCore:
+                case Int64ManifestNetFx:
+                    return BitConverter.ToInt64(bytes, 0);
+                default:
+                    throw new ArgumentException($"Unimplemented deserialization of message with manifest [{manifest}] in [${GetType()}]");
+            }
+        }
 
-            throw new ArgumentException($"Unimplemented deserialization of message with manifest [{type.TypeQualifiedName()}] in [${nameof(PrimitiveSerializers)}]");
+        /// <inheritdoc />
+        public override string Manifest(object obj)
+        {
+            switch (obj)
+            {
+                case string _:
+                    return StringManifest;
+                case int _:
+                    return Int32Manifest;
+                case long _:
+                    return Int64Manifest;
+                default:
+                    throw new ArgumentException($"Cannot serialize object of type [{obj.GetType()}] in [{GetType()}]");
+            }
         }
     }
 }