Add details about generic-type parameters in IGrainStorage interface impl

docs/orleans/tutorials-and-samples/custom-grain-storage.md

@@ -1,15 +1,15 @@
 ---
 title: Custom grain storage sample project
 description: Explore a custom grain storage sample project written with .NET Orleans.
-ms.date: 12/08/2022
+ms.date: 02/27/2023
 zone_pivot_groups: orleans-version
 ---
 
 # Custom grain storage
 
 In the tutorial on declarative actor storage, we looked at allowing grains to store their state in an Azure table using one of the built-in storage providers. While Azure is a great place to squirrel away your data, there are many alternatives. There are so many that there was no way to support them all. Instead, Orleans is designed to let you easily add support for your form of storage by writing a grain storage.
 
-In this tutorial, we'll walk through how to write simple file-based grain storage. A file system is not the best place to store grains states as it is local, there can be issues with file locks and the last update date is not sufficient to prevent inconsistency. But it's an easy example to help us illustrate the implementation of a `Grain Storage`.
+In this tutorial, we'll walk through how to write simple file-based grain storage. A file system is not the best place to store grains states as it is local, there can be issues with file locks and the last update date is not sufficient to prevent inconsistency. But it's an easy example to help us illustrate the implementation of a _grain storage_.
 
 ## Get started
 
@@ -72,6 +72,14 @@ public sealed class FileGrainStorage : IGrainStorage, ILifecycleParticipant<ISil
 }
 ```
 
+Each method implements the corresponding method in the [IGrainStorage](xref:Orleans.Storage.IGrainStorage) interface, accepting a generic-type parameter for the underlying state type. The methods are:
+
+- <xref:Orleans.Storage.IGrainStorage.ReadStateAsync%2A?displayProperty=nameWithType>: to read the state of a grain.
+- <xref:Orleans.Storage.IGrainStorage.WriteStateAsync%2A?displayProperty=nameWithType>: to write the state of a grain.
+- <xref:Orleans.Storage.IGrainStorage.ClearStateAsync%2A?displayProperty=nameWithType>: to clear the state of a grain.
+
+The <xref:Orleans.ILifecycleParticipant%601.Participate%2A?displayProperty=nameWithType> method is used to subscribe to the lifecycle of the silo.
+
 Before starting the implementation, you'll create an options class containing the root directory where the grain state files are persisted. For that you'll create an options file named `FileGrainStorageOptions` containing the following:
 
 :::code source="snippets/custom-grain-storage/FileGrainStorageOptions.cs":::

docs/orleans/tutorials-and-samples/snippets/custom-grain-storage/FileGrainStorage.cs

@@ -34,10 +34,10 @@ public Task ClearStateAsync<T>(
         {
             if (fileInfo.LastWriteTimeUtc.ToString() != grainState.ETag)
             {
-                throw new InconsistentStateException($$"""
-                    Version conflict (ClearState): ServiceId={{_clusterOptions.ServiceId}}
-                    ProviderName={{_storageName}} GrainType={{typeof(T)}} 
-                    GrainReference={{grainId}}.
+                throw new InconsistentStateException($"""
+                    Version conflict (ClearState): ServiceId={_clusterOptions.ServiceId}
+                    ProviderName={_storageName} GrainType={typeof(T)}
+                    GrainReference={grainId}.
                     """);
             }
 
@@ -57,7 +57,7 @@ public async Task ReadStateAsync<T>(
         IGrainState<T> grainState)
     {
         var fName = GetKeyString(stateName, grainId);
-        var path = Path.Combine(_options.RootDirectory, fName!);        
+        var path = Path.Combine(_options.RootDirectory, fName!);
         var fileInfo = new FileInfo(path);
         if (fileInfo is { Exists: false })
         {
@@ -84,10 +84,10 @@ public async Task WriteStateAsync<T>(
         var fileInfo = new FileInfo(path);
         if (fileInfo.Exists && fileInfo.LastWriteTimeUtc.ToString() != grainState.ETag)
         {
-            throw new InconsistentStateException($$"""
-                Version conflict (WriteState): ServiceId={{_clusterOptions.ServiceId}}
-                ProviderName={{_storageName}} GrainType={{typeof(T)}} 
-                GrainReference={{grainId}}.
+            throw new InconsistentStateException($"""
+                Version conflict (WriteState): ServiceId={_clusterOptions.ServiceId}
+                ProviderName={_storageName} GrainType={typeof(T)}
+                GrainReference={grainId}.
                 """);
         }
 

docs/orleans/tutorials-and-samples/snippets/custom-grain-storage/FileGrainStorageFactory.cs

@@ -10,13 +10,13 @@ internal static class FileGrainStorageFactory
     internal static IGrainStorage Create(
         IServiceProvider services, string name)
     {
-        var optionsSnapshot =
-            services.GetRequiredService<IOptionsSnapshot<FileGrainStorageOptions>>();
+        var optionsMonitor =
+            services.GetRequiredService<IOptionsMonitor<FileGrainStorageOptions>>();
 
         return ActivatorUtilities.CreateInstance<FileGrainStorage>(
             services,
             name,
-            optionsSnapshot.Get(name),
+            optionsMonitor.Get(name),
             services.GetProviderClusterOptions(name));
     }
 }