Eliminated GrainState

src/Orleans/CodeGeneration/TypeUtils.cs

@@ -442,17 +442,7 @@ public static bool IsGrainMethodInvokerType(Type type)
             }
             return generalType.GetTypeInfo().IsAssignableFrom(type) && TypeHasAttribute(type, typeof(MethodInvokerAttribute));        
         }
-
-        public static bool IsGrainStateType(Type type)
-        {
-            var generalType = typeof(GrainState);
-            if (type.Assembly.ReflectionOnly)
-            {
-                generalType = ToReflectionOnlyType(generalType);
-            }
-            return generalType.GetTypeInfo().IsAssignableFrom(type) && TypeHasAttribute(type, typeof(GrainStateAttribute));
-        }
-
+
         public static Type ResolveType(string fullName)
         {
             return CachedTypeResolver.Instance.ResolveType(fullName);

src/Orleans/Core/Grain.cs

@@ -41,7 +41,7 @@ public abstract class Grain : IAddressable
     {
         private IGrainRuntime runtime;
 
-        internal GrainState GrainState { get; set; }
+        internal object GrainState { get; set; }
 
         internal IStorage Storage { get; set; }
 
@@ -278,8 +278,8 @@ internal string CaptureRuntimeEnvironment()
     /// Base class for a Grain with declared persistent state.
     /// </summary>
     /// <typeparam name="TGrainState">The class of the persistent state object</typeparam>
-    public class Grain<TGrainState> : Grain
-        where TGrainState : GrainState
+    public class Grain<TGrainState> : Grain 
+        where TGrainState : class
     {
 
         /// <summary>
@@ -310,7 +310,7 @@ protected Grain(IGrainIdentity identity, IGrainRuntime runtime, TGrainState stat
         /// </summary>
         protected TGrainState State
         {
-            get { return base.GrainState as TGrainState; }
+            get { return (TGrainState)GrainState; }
         }
 
         protected virtual Task ClearStateAsync()

src/Orleans/Core/GrainStateStorageBridge.cs

@@ -37,6 +37,7 @@ internal class GrainStateStorageBridge : IStorage
         private readonly IStorageProvider store;
         private readonly Grain grain;
         private readonly string grainTypeName;
+        private string eTag;
 
         public GrainStateStorageBridge(string grainTypeName, Grain grain, IStorageProvider store)
         {
@@ -68,8 +69,13 @@ public async Task ReadStateAsync()
             GrainReference grainRef = grain.GrainReference;
             try
             {
-                await store.ReadStateAsync(grainTypeName, grainRef, grain.GrainState);
-
+                var etagged = await store.ReadStateAsync(grainTypeName, grainRef, grain.GrainState);
+                grain.GrainState = etagged.State;
+                if (!string.IsNullOrEmpty(etagged.ETag))
+                {
+                    eTag = etagged.ETag;
+                }
+
                 StorageStatisticsGroup.OnStorageRead(store, grainTypeName, grainRef, sw.Elapsed);
             }
             catch (Exception exc)
@@ -97,8 +103,7 @@ public async Task WriteStateAsync()
             Exception errorOccurred;
             try
             {
-                await store.WriteStateAsync(grainTypeName, grainRef, grain.GrainState);
-
+                eTag = await store.WriteStateAsync(grainTypeName, grainRef, new ETagged<object>(grain.GrainState, eTag));
                 StorageStatisticsGroup.OnStorageWrite(store, grainTypeName, grainRef, sw.Elapsed);
                 errorOccurred = null;
             }
@@ -152,9 +157,10 @@ public async Task ClearStateAsync()
             try
             {
                 // Clear (most likely Delete) state from external storage
-                await store.ClearStateAsync(grainTypeName, grainRef, grain.GrainState);
+                eTag = await store.ClearStateAsync(grainTypeName, grainRef, new ETagged<object>(grain.GrainState, eTag));
+
                 // Null out the in-memory copy of the state
-                grain.GrainState.SetAll(null);
+                grain.GrainState = null;
 
                 // Update counters
                 StorageStatisticsGroup.OnStorageDelete(store, grainTypeName, grainRef, sw.Elapsed);

src/Orleans/Orleans.csproj

@@ -90,14 +90,14 @@
     <Compile Include="Async\UnobservedExceptionsHandlerClass.cs" />
     <Compile Include="Async\TaskExtensions.cs" />
     <Compile Include="CodeGeneration\CodeGeneratorManager.cs" />
-    <Compile Include="CodeGeneration\GrainState.cs" />
     <Compile Include="CodeGeneration\ICodeGeneratorCache.cs" />
     <Compile Include="CodeGeneration\IGrainMethodInvoker.cs" />
     <Compile Include="CodeGeneration\IRuntimeCodeGenerator.cs" />
     <Compile Include="CodeGeneration\ISourceCodeGenerator.cs" />
     <Compile Include="CodeGeneration\Language.cs" />
     <Compile Include="CodeGeneration\OrleansCodeGenerationTargetAttribute.cs" />
     <Compile Include="CodeGeneration\SkipCodeGenerationAttribute.cs" />
+    <Compile Include="Runtime\ETagged.cs" />
     <Compile Include="Serialization\IExternalSerializer.cs" />
     <Compile Include="Configuration\LimitNames.cs" />
     <Compile Include="Configuration\LimitValue.cs" />
@@ -416,4 +416,4 @@
     <Message Text="[OrleansDllBootstrapUsingCodeGen] - Invoking Code Generator" />
     <Exec Command="&quot;$(BootstrapOutputPath)ClientGenerator.exe&quot; &quot;@$(ArgsFile)&quot;" />
   </Target>
-</Project>
+</Project>

src/Orleans/Providers/IMemoryStorageGrain.cs

@@ -23,6 +23,7 @@ MIT License
 
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Orleans.Runtime;
 
 namespace Orleans.Storage
 {
@@ -37,7 +38,7 @@ public interface IMemoryStorageGrain : IGrainWithIntegerKey
         /// <param name="grainType">Type of this grain [fully qualified class name]</param>
         /// <param name="grainId">Grain id for this grain.</param>
         /// <returns>Value promise for the currently stored grain state for the specified grain.</returns>
-        Task<IDictionary<string, object>> ReadStateAsync(string grainType, string grainId);
+        Task<ETagged<object>> ReadStateAsync(string grainType, string grainId);
 
         /// <summary>
         /// Async method to cause update of the specified grain state data into memory store.
@@ -46,14 +47,14 @@ public interface IMemoryStorageGrain : IGrainWithIntegerKey
         /// <param name="grainId">Grain id for this grain.</param>
         /// <param name="grainState">New state data to be stored for this grain.</param>
         /// <returns>Completion promise for the update operation for stored grain state for the specified grain.</returns>
-        Task WriteStateAsync(string grainType, string grainId, IDictionary<string, object> grainState);
+        Task WriteStateAsync(string grainType, string grainId, ETagged<object> grainState);
 
         /// <summary>
         /// Async method to cause deletion of the specified grain state data from memory store.
         /// </summary>
         /// <param name="grainType">Type of this grain [fully qualified class name]</param>
         /// <param name="grainId">Grain id for this grain.</param>
         /// <returns>Completion promise for the update operation for stored grain state for the specified grain.</returns>
-        Task DeleteStateAsync(string grainType, string grainId);
+        Task DeleteStateAsync(string grainType, string grainId, string etag);
     }
 }

src/Orleans/Providers/IStorageProvider.cs

@@ -25,7 +25,7 @@ MIT License
 using System.Net;
 using System.Runtime.Serialization;
 using System.Threading.Tasks;
-
+using Orleans.Core;
 using Orleans.Runtime;
 using Orleans.Providers;
 
@@ -46,21 +46,21 @@ public interface IStorageProvider : IProvider
         /// <param name="grainReference">Grain reference object for this grain.</param>
         /// <param name="grainState">State data object to be populated for this grain.</param>
         /// <returns>Completion promise for the Read operation on the specified grain.</returns>
-        Task ReadStateAsync(string grainType, GrainReference grainReference, GrainState grainState);
+        Task<ETagged<TState>> ReadStateAsync<TState>(string grainType, GrainReference grainReference, TState grainState);
 
         /// <summary>Write data function for this storage provider instance.</summary>
         /// <param name="grainType">Type of this grain [fully qualified class name]</param>
         /// <param name="grainReference">Grain reference object for this grain.</param>
         /// <param name="grainState">State data object to be written for this grain.</param>
         /// <returns>Completion promise for the Write operation on the specified grain.</returns>
-        Task WriteStateAsync(string grainType, GrainReference grainReference, GrainState grainState);
+        Task<string> WriteStateAsync(string grainType, GrainReference grainReference, ETagged<object> grainState);
 
         /// <summary>Delete / Clear data function for this storage provider instance.</summary>
         /// <param name="grainType">Type of this grain [fully qualified class name]</param>
         /// <param name="grainReference">Grain reference object for this grain.</param>
         /// <param name="grainState">Copy of last-known state data object for this grain.</param>
         /// <returns>Completion promise for the Delete operation on the specified grain.</returns>
-        Task ClearStateAsync(string grainType, GrainReference grainReference, GrainState grainState);
+        Task<string> ClearStateAsync(string grainType, GrainReference grainReference, ETagged<object> grainState);
     }
 
     /// <summary>