DeleteStateOnClear support for AdoNet storage provider

src/AdoNet/Orleans.Persistence.AdoNet/Options/AdoNetGrainStorageOptions.cs

@@ -35,6 +35,11 @@ public class AdoNetGrainStorageOptions : IStorageProviderSerializerOptions
 
         /// <inheritdoc/>
         public IGrainStorageSerializer GrainStorageSerializer { get; set; }
+
+        /// <summary>
+        /// Delete record row from db when state is cleared.
+        /// </summary>
+        public bool DeleteStateOnClear { get; set; } = false;
     }
 
     /// <summary>

src/AdoNet/Orleans.Persistence.AdoNet/PostgreSQL-Persistence.sql

@@ -180,3 +180,20 @@ VALUES
         AND Version IS NOT NULL AND Version = @GrainStateVersion AND @GrainStateVersion IS NOT NULL
     Returning Version as NewGrainStateVersion
 ');
+
+INSERT INTO OrleansQuery(QueryKey, QueryText)
+VALUES
+(
+    'DeleteStorageKey','
+    DELETE FROM OrleansStorage
+    WHERE
+        GrainIdHash = @GrainIdHash AND @GrainIdHash IS NOT NULL
+        AND GrainTypeHash = @GrainTypeHash AND @GrainTypeHash IS NOT NULL
+        AND GrainIdN0 = @GrainIdN0 AND @GrainIdN0 IS NOT NULL
+        AND GrainIdN1 = @GrainIdN1 AND @GrainIdN1 IS NOT NULL
+        AND GrainTypeString = @GrainTypeString AND @GrainTypeString IS NOT NULL
+        AND ((@GrainIdExtensionString IS NOT NULL AND GrainIdExtensionString IS NOT NULL AND GrainIdExtensionString = @GrainIdExtensionString) OR @GrainIdExtensionString IS NULL AND GrainIdExtensionString IS NULL)
+        AND ServiceId = @ServiceId AND @ServiceId IS NOT NULL
+        AND Version IS NOT NULL AND Version = @GrainStateVersion AND @GrainStateVersion IS NOT NULL
+    Returning Version + 1 as NewGrainStateVersion
+');

src/AdoNet/Orleans.Persistence.AdoNet/SQLServer-Persistence.sql

@@ -246,3 +246,24 @@ VALUES
         AND ServiceId = @ServiceId AND @ServiceId IS NOT NULL
         OPTION(FAST 1, OPTIMIZE FOR(@GrainIdHash UNKNOWN, @GrainTypeHash UNKNOWN));'
 );
+
+INSERT INTO OrleansQuery(QueryKey, QueryText)
+VALUES
+(
+    'DeleteStorageKey',
+    'BEGIN TRANSACTION;
+    SET XACT_ABORT, NOCOUNT ON;
+    DELETE FROM OrleansStorage OUTPUT DELETED.Version + 1
+    WHERE
+        GrainIdHash = @GrainIdHash AND @GrainIdHash IS NOT NULL
+        AND GrainTypeHash = @GrainTypeHash AND @GrainTypeHash IS NOT NULL
+        AND (GrainIdN0 = @GrainIdN0 OR @GrainIdN0 IS NULL)
+        AND (GrainIdN1 = @GrainIdN1 OR @GrainIdN1 IS NULL)
+        AND (GrainTypeString = @GrainTypeString OR @GrainTypeString IS NULL)
+        AND ((@GrainIdExtensionString IS NOT NULL AND GrainIdExtensionString IS NOT NULL AND GrainIdExtensionString = @GrainIdExtensionString) OR @GrainIdExtensionString IS NULL AND GrainIdExtensionString IS NULL)
+        AND ServiceId = @ServiceId AND @ServiceId IS NOT NULL
+        AND Version IS NOT NULL AND Version = @GrainStateVersion AND @GrainStateVersion IS NOT NULL
+        OPTION(FAST 1, OPTIMIZE FOR(@GrainIdHash UNKNOWN, @GrainTypeHash UNKNOWN));
+
+    COMMIT TRANSACTION;'
+);

src/AdoNet/Orleans.Persistence.AdoNet/Storage/Provider/AdoNetGrainStorage.cs

@@ -108,7 +108,7 @@ public class AdoNetGrainStorage: IGrainStorage, ILifecycleParticipant<ISiloLifec
         /// <summary>
         /// The default query to initialize this structure from the Orleans database.
         /// </summary>
-        public const string DefaultInitializationQuery = "SELECT QueryKey, QueryText FROM OrleansQuery WHERE QueryKey = 'WriteToStorageKey' OR QueryKey = 'ReadFromStorageKey' OR QueryKey = 'ClearStorageKey'";
+        public const string DefaultInitializationQuery = "SELECT QueryKey, QueryText FROM OrleansQuery WHERE QueryKey = 'WriteToStorageKey' OR QueryKey = 'ReadFromStorageKey' OR QueryKey = 'ClearStorageKey' OR QueryKey = 'DeleteStorageKey'";
 
         /// <summary>
         /// The queries currently used. When this is updated, the new queries will take effect immediately.
@@ -155,20 +155,29 @@ public async Task ClearStateAsync<T>(string grainType, GrainId grainReference, I
             {
                 logger.LogTrace(
                     (int)RelationalStorageProviderCodes.RelationalProviderClearing,
-                    "Clearing grain state: ServiceId={ServiceId} ProviderName={Name} GrainType={BaseGrainType} GrainId={GrainId} ETag={ETag}.",
+                    "Clearing grain state: ServiceId={ServiceId} ProviderName={Name} GrainType={BaseGrainType} GrainId={GrainId} ETag={ETag} DeleteStateOnClear={DeleteStateOnClear}.",
                     serviceId,
                     name,
                     baseGrainType,
                     grainId,
-                    grainState.ETag);
+                    grainState.ETag,
+                    options.DeleteStateOnClear);
             }
 
             string storageVersion = null;
             try
             {
                 var grainIdHash = HashPicker.PickHasher(serviceId, this.name, baseGrainType, grainReference, grainState).Hash(grainId.GetHashBytes());
                 var grainTypeHash = HashPicker.PickHasher(serviceId, this.name, baseGrainType, grainReference, grainState).Hash(Encoding.UTF8.GetBytes(baseGrainType));
-                var clearRecord = (await Storage.ReadAsync(CurrentOperationalQueries.ClearState, command =>
+
+                var queryText = options.DeleteStateOnClear ? CurrentOperationalQueries.DeleteState : CurrentOperationalQueries.ClearState;
+                //Backward compatibility checks in Init should handle this case and throw prior to reaching this state.
+                if (queryText is null)
+                {
+                    //We should not be here.
+                    throw new UnreachableException($"QueryText is null for options.DeleteStateOnClear={options.DeleteStateOnClear}");
+                }
+                var clearRecord = (await Storage.ReadAsync(queryText, command =>
                 {
                     command.AddParameter("GrainIdHash", grainIdHash);
                     command.AddParameter("GrainIdN0", grainId.N0Key);
@@ -202,8 +211,9 @@ public async Task ClearStateAsync<T>(string grainType, GrainId grainReference, I
                 throw inconsistentStateException;
             }
 
+            //if delete on clear is set, ETag should be set to null since record has been deleted, but db script returns deleted record version + 1 as storageVersion for CheckVersionInconsistency method.
             //No errors found, the version of the state held by the grain can be updated and also the state.
-            grainState.ETag = storageVersion;
+            grainState.ETag = options.DeleteStateOnClear ? null : storageVersion;
             grainState.RecordExists = false;
             if(logger.IsEnabled(LogLevel.Trace))
             {
@@ -409,10 +419,19 @@ private async Task Init(CancellationToken cancellationToken)
                 return Task.FromResult(Tuple.Create(selector.GetValue<string>("QueryKey"), selector.GetValue<string>("QueryText")));
             }).ConfigureAwait(false);
 
+            //This check is for backward compatibility:
+            //1. Some AdoNet storage invariants may not support delete on clear
+            //2. AdoNet invariant supports delete on clear but updated persistence scripts have not been deployed to management db.
+            var deleteStateQuery = queries.SingleOrDefault(i => i.Item1 == "DeleteStorageKey")?.Item2;
+            if (options.DeleteStateOnClear && deleteStateQuery is null)
+            {
+                throw new ArgumentException("DeleteStateOnClear=true option is not supported. Use options.DeleteStateOnClear=false instead or check persistence scripts.");
+            }
             CurrentOperationalQueries = new RelationalStorageProviderQueries(
                 queries.Single(i => i.Item1 == "WriteToStorageKey").Item2,
                 queries.Single(i => i.Item1 == "ReadFromStorageKey").Item2,
-                queries.Single(i => i.Item1 == "ClearStorageKey").Item2);
+                queries.Single(i => i.Item1 == "ClearStorageKey").Item2,
+                deleteStateQuery);
 
             logger.LogInformation(
                 (int)RelationalStorageProviderCodes.RelationalProviderInitProvider,

src/AdoNet/Orleans.Persistence.AdoNet/Storage/Provider/RelationalStorageProviderQueries.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 
 
 namespace Orleans.Storage
@@ -24,14 +24,19 @@ public class RelationalStorageProviderQueries
         /// </summary>
         public string ClearState { get; set; }
 
+        /// <summary>
+        /// The clause to clear the storage, deleting row in db.
+        /// </summary>
+        public string DeleteState { get; set; }
+
 
         /// <summary>
         /// Constructor.
         /// </summary>
         /// <param name="writeToStorage">The clause to write to a storage.</param>
         /// <param name="readFromStorage">The clause to read from a storage.</param>
         /// <param name="clearState">The clause to clear the storage.</param>
-        public RelationalStorageProviderQueries(string writeToStorage, string readFromStorage, string clearState)
+        public RelationalStorageProviderQueries(string writeToStorage, string readFromStorage, string clearState, string deleteState)
         {
             if(writeToStorage == null)
             {
@@ -48,9 +53,12 @@ public RelationalStorageProviderQueries(string writeToStorage, string readFromSt
                 throw new ArgumentNullException(nameof(clearState));
             }
 
+            //no null check on deleteState for backward compatibility
+
             WriteToStorage = writeToStorage;
             ReadFromStorage = readFromStorage;
             ClearState = clearState;
+            DeleteState = deleteState;
         }
     }
 }