Orleans: System.TypeAccessException: Named type "..." is invalid: Type string "..." cannot be resolved.

[alexandrnikitin]

I believe I encounter a bug. It seems Orleans doesn't work well with generic type that is located in another project. Could be related to #4012
I've prepared a minimal repro project for the case: https://github.com/alexandrnikitin/orleans-repro-4188

To reproduce:

cd \samples\GoogleHashcode2018
>BuildAndRun.ps1

Observe Client console app output. The following exception appears:

System.AggregateException: One or more errors occurred. (Named type "DMCTS.Grains.NodeView`1<Rides.MakeRideAction>" is invalid: Type string "Rides.MakeRideAction" cannot be resolved.) ---> System.TypeAccessException: Named type "DMCTS.Grains.NodeView`1<Rides.MakeRideAction>" is invalid: Type string "Rides.MakeRideAction" cannot be resolved.
   at Orleans.Serialization.BinaryTokenStreamReaderExtensinons.ReadSpecifiedTypeHeader(IBinaryTokenStreamReader this, SerializationManager serializationManager)
   at Orleans.Serialization.SerializationManager.DeserializeInner(Type expected, IDeserializationContext context)
   at Orleans.Serialization.BuiltInTypes.DeserializeOrleansResponse(Type expected, IDeserializationContext context)
   at Orleans.Serialization.SerializationManager.DeserializeInner(Type expected, IDeserializationContext context)
   at Orleans.Serialization.SerializationManager.Deserialize(Type t, IBinaryTokenStreamReader stream)
   at Orleans.Runtime.Message.GetDeserializedBody(SerializationManager serializationManager)
   at Orleans.Runtime.GrainReferenceRuntime.ResponseCallback(Message message, TaskCompletionSource`1 context)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Orleans.OrleansTaskExtentions.<<ToTypedTask>g__ConvertAsync4_0>d`1.MoveNext()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at Rides.Client.Program.<DoClientWork>d__3.MoveNext() in C:\projects\my\DistributedMonteCarloTreeSearch.NET\samples\GoogleHashcode2018\Rides.Client\Program.cs:line 81
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Rides.Client.Program.<RunMainAsync>d__1.MoveNext() in C:\projects\my\DistributedMonteCarloTreeSearch.NET\samples\GoogleHashcode2018\Rides.Client\Program.cs:line 26
---> (Inner Exception #0) System.TypeAccessException: Named type "DMCTS.Grains.NodeView`1<Rides.MakeRideAction>" is invalid: Type string "Rides.MakeRideAction" cannot be resolved.
   at Orleans.Serialization.BinaryTokenStreamReaderExtensinons.ReadSpecifiedTypeHeader(IBinaryTokenStreamReader this, SerializationManager serializationManager)
   at Orleans.Serialization.SerializationManager.DeserializeInner(Type expected, IDeserializationContext context)
   at Orleans.Serialization.BuiltInTypes.DeserializeOrleansResponse(Type expected, IDeserializationContext context)
   at Orleans.Serialization.SerializationManager.DeserializeInner(Type expected, IDeserializationContext context)
   at Orleans.Serialization.SerializationManager.Deserialize(Type t, IBinaryTokenStreamReader stream)
   at Orleans.Runtime.Message.GetDeserializedBody(SerializationManager serializationManager)
   at Orleans.Runtime.GrainReferenceRuntime.ResponseCallback(Message message, TaskCompletionSource`1 context)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Orleans.OrleansTaskExtentions.<<ToTypedTask>g__ConvertAsync4_0>d`1.MoveNext()<---

[ReubenBond]

@alexandrnikitin there are 3 ways you can fix this:

1. The project containing MakeRideAction can include Microsoft.Orleans.OrleansCodeGenerator.Build and Microsoft.Orleans.Core.Abstractions packages.

2. The client/silo projects can have an assembly level attribute to instruct the code generator to generate code for Rides also, like so:
   ```C#
   [assembly: KnownAssembly(typeof(Rides.MakeRideAction))]

// on the builder:
.ConfigureApplicationParts(parts => parts.AddApplicationPart(typeof(ITreeGrain<>).Assembly))
.ConfigureApplicationParts(parts => parts.AddApplicationPart(typeof(NodeView<>).Assembly))
.ConfigureApplicationParts(parts => parts.AddApplicationPart(typeof(Program).Assembly))

3. You can generate code for `Rides` during startup by installing `Microsoft.Orleans.OrleansCodeGenerator`  into the client/silo and using `WithCodeGeneration()` on both client and silo during configuration time, like so:
```C#
.ConfigureApplicationParts(parts => parts.AddApplicationPart(typeof(MakeRideAction).Assembly).WithCodeGeneration())

This requires that Rides includes Microsoft.Orleans.Core.Abstractions, since we filter it out otherwise.

Assuming you don't want to modify Rides.csproj, your best option out of these is the second: use KnownAssembly to generate code into a different project (you could also generate it into a special purpose project and then include that using ApplicationParts, or generate it into your interfaces project).

Hope that helps

[alexandrnikitin]

Great! It helped! Thank you for the prompt response.