Akka.Persistence: Made DateTime.UtcNow the default timestamp for SnapshotMetdata

src/contrib/persistence/Akka.Persistence.Sql.Common/Snapshot/QueryExecutor.cs

@@ -463,7 +463,7 @@ public virtual async Task DeleteAsync(
             await connection.ExecuteInTransaction(WriteIsolationLevel, cancellationToken, async (tx, token) =>
             {
                 var sql = timestamp.HasValue
-                    ? DeleteSnapshotRangeSql + " AND { Configuration.TimestampColumnName} = @Timestamp"
+                    ? DeleteSnapshotSql + $" AND {Configuration.TimestampColumnName} <= @Timestamp"
                     : DeleteSnapshotSql;
 
                 using var command = GetCommand(connection, sql); 

src/core/Akka.API.Tests/verify/CoreAPISpec.ApprovePersistence.DotNet.verified.txt

@@ -587,7 +587,8 @@ namespace Akka.Persistence
     }
     public sealed class SnapshotMetadata : System.IEquatable<Akka.Persistence.SnapshotMetadata>
     {
-        public static System.DateTime TimestampNotSpecified;
+        [System.ObsoleteAttribute("This constructor is deprecated and will be removed in v1.6. Use the constructor w" +
+            "ith the timestamp parameter instead. Since v1.5.28", true)]
         public SnapshotMetadata(string persistenceId, long sequenceNr) { }
         [Newtonsoft.Json.JsonConstructorAttribute()]
         public SnapshotMetadata(string persistenceId, long sequenceNr, System.DateTime timestamp) { }

src/core/Akka.API.Tests/verify/CoreAPISpec.ApprovePersistence.Net.verified.txt

@@ -587,7 +587,8 @@ namespace Akka.Persistence
     }
     public sealed class SnapshotMetadata : System.IEquatable<Akka.Persistence.SnapshotMetadata>
     {
-        public static System.DateTime TimestampNotSpecified;
+        [System.ObsoleteAttribute("This constructor is deprecated and will be removed in v1.6. Use the constructor w" +
+            "ith the timestamp parameter instead. Since v1.5.28", true)]
         public SnapshotMetadata(string persistenceId, long sequenceNr) { }
         [Newtonsoft.Json.JsonConstructorAttribute()]
         public SnapshotMetadata(string persistenceId, long sequenceNr, System.DateTime timestamp) { }

src/core/Akka.Persistence.TCK.Tests/LocalSnapshotStoreSpec.cs

@@ -42,7 +42,7 @@ protected override void AfterAll()
         public void LocalSnapshotStore_can_snapshot_actors_with_PersistenceId_containing_invalid_path_characters()
         {
             var pid = @"p\/:*?-1";
-            SnapshotStore.Tell(new SaveSnapshot(new SnapshotMetadata(pid, 1), "sample data"), TestActor);
+            SnapshotStore.Tell(new SaveSnapshot(new SnapshotMetadata(pid, 1, Sys.Scheduler.Now.DateTime), "sample data"), TestActor);
             ExpectMsg<SaveSnapshotSuccess>();
 
             SnapshotStore.Tell(new LoadSnapshot(pid, SnapshotSelectionCriteria.Latest, long.MaxValue), TestActor);

src/core/Akka.Persistence.TCK/Query/PersistenceIdsSpec.cs

@@ -247,7 +247,7 @@ protected IActorRef WriteSnapshot(string persistenceId, int n)
                 ExpectMsg($"{persistenceId}-{i}-done");
             }
 
-            var metadata = new SnapshotMetadata(persistenceId, n + 10);
+            var metadata = new SnapshotMetadata(persistenceId, n + 10, Sys.Scheduler.Now.DateTime);
             SnapshotStore.Tell(new SaveSnapshot(metadata, $"s-{n}"), _senderProbe.Ref);
             _senderProbe.ExpectMsg<SaveSnapshotSuccess>();
 

src/core/Akka.Persistence.TCK/Serialization/SnapshotStoreSerializationSpec.cs

@@ -69,7 +69,7 @@ public virtual void SnapshotStore_should_serialize_Payload()
 
             var snapshot = new Test.MySnapshot("a");
 
-            var metadata = new SnapshotMetadata(Pid, 1);
+            var metadata = new SnapshotMetadata(Pid, 1, Sys.Scheduler.Now.DateTime);
             SnapshotStore.Tell(new SaveSnapshot(metadata, snapshot), probe.Ref);
             probe.ExpectMsg<SaveSnapshotSuccess>();
 
@@ -85,7 +85,7 @@ public virtual void SnapshotStore_should_serialize_Payload_with_string_manifest(
 
             var snapshot = new Test.MySnapshot2("a");
 
-            var metadata = new SnapshotMetadata(Pid, 1);
+            var metadata = new SnapshotMetadata(Pid, 1, Sys.Scheduler.Now.DateTime);
             SnapshotStore.Tell(new SaveSnapshot(metadata, snapshot), probe.Ref);
             probe.ExpectMsg<SaveSnapshotSuccess>();
 
@@ -107,7 +107,7 @@ public virtual void SnapshotStore_should_serialize_AtLeastOnceDeliverySnapshot()
             };
             var atLeastOnceDeliverySnapshot = new AtLeastOnceDeliverySnapshot(17, unconfirmed);
 
-            var metadata = new SnapshotMetadata(Pid, 2);
+            var metadata = new SnapshotMetadata(Pid, 2, Sys.Scheduler.Now.DateTime);
             SnapshotStore.Tell(new SaveSnapshot(metadata, atLeastOnceDeliverySnapshot), probe.Ref);
             probe.ExpectMsg<SaveSnapshotSuccess>();
 
@@ -123,7 +123,7 @@ public virtual void SnapshotStore_should_serialize_AtLeastOnceDeliverySnapshot_w
             var unconfirmed = Array.Empty<UnconfirmedDelivery>();
             var atLeastOnceDeliverySnapshot = new AtLeastOnceDeliverySnapshot(13, unconfirmed);
 
-            var metadata = new SnapshotMetadata(Pid, 2);
+            var metadata = new SnapshotMetadata(Pid, 2, Sys.Scheduler.Now.DateTime);
             SnapshotStore.Tell(new SaveSnapshot(metadata, atLeastOnceDeliverySnapshot), probe.Ref);
             probe.ExpectMsg<SaveSnapshotSuccess>();
 
@@ -138,7 +138,7 @@ public virtual void SnapshotStore_should_serialize_PersistentFSMSnapshot()
 
             var persistentFSMSnapshot = new PersistentFSM.PersistentFSMSnapshot<string>("mystate", "mydata", TimeSpan.FromDays(4));
 
-            var metadata = new SnapshotMetadata(Pid, 2);
+            var metadata = new SnapshotMetadata(Pid, 2, Sys.Scheduler.Now.DateTime);
             SnapshotStore.Tell(new SaveSnapshot(metadata, persistentFSMSnapshot), probe.Ref);
             probe.ExpectMsg<SaveSnapshotSuccess>();
 

src/core/Akka.Persistence.TCK/Snapshot/SnapshotStoreSpec.cs

@@ -14,6 +14,7 @@
 using Akka.Persistence.Fsm;
 using Akka.Persistence.TCK.Serialization;
 using Akka.TestKit;
+using FluentAssertions.Extensions;
 using Xunit;
 using Xunit.Abstractions;
 
@@ -100,7 +101,7 @@ private IEnumerable<SnapshotMetadata> WriteSnapshots()
         {
             for (int i = 1; i <= 5; i++)
             {
-                var metadata = new SnapshotMetadata(Pid, i + 10);
+                var metadata = new SnapshotMetadata(Pid, i + 10, Sys.Scheduler.Now.DateTime);
                 SnapshotStore.Tell(new SaveSnapshot(metadata, $"s-{i}"), _senderProbe.Ref);
                 yield return _senderProbe.ExpectMsg<SaveSnapshotSuccess>().Metadata;
             }
@@ -177,11 +178,13 @@ public virtual void SnapshotStore_should_load_the_most_recent_snapshot_matching_
                 && result.Snapshot.Snapshot.ToString() == "s-3");
         }
 
+        // Issue #7312
+        // Backward compatibility check, SnapshotMetadata .ctor should work if we pass in UtcNow
         [Fact]
         public virtual void SnapshotStore_should_delete_a_single_snapshot_identified_by_SequenceNr_in_snapshot_metadata()
         {
             var md = Metadata[2];
-            md = new SnapshotMetadata(md.PersistenceId, md.SequenceNr); // don't care about timestamp for delete of a single snap
+            md = new SnapshotMetadata(md.PersistenceId, md.SequenceNr, Sys.Scheduler.Now.DateTime);
             var command = new DeleteSnapshot(md);
             var sub = CreateTestProbe();
 
@@ -198,6 +201,54 @@ public virtual void SnapshotStore_should_delete_a_single_snapshot_identified_by_
                 && result.Snapshot.Snapshot.ToString() == "s-2");
         }
 
+        // Issue #7312
+        // Backward compatibility check, old SnapshotMetadata .ctor default value should work as expected
+        [Fact]
+        public virtual void SnapshotStore_should_delete_a_single_snapshot_identified_by_SequenceNr_in_snapshot_metadata_if_timestamp_is_MinValue()
+        {
+            var md = Metadata[2];
+            // In previous incarnation, timestamp argument defaults to DateTime.MinValue
+            md = new SnapshotMetadata(md.PersistenceId, md.SequenceNr, DateTime.MinValue);
+            var command = new DeleteSnapshot(md);
+            var sub = CreateTestProbe();
+
+            Subscribe<DeleteSnapshot>(sub.Ref);
+            SnapshotStore.Tell(command, _senderProbe.Ref);
+            sub.ExpectMsg(command);
+            _senderProbe.ExpectMsg<DeleteSnapshotSuccess>();
+
+            SnapshotStore.Tell(new LoadSnapshot(Pid, new SnapshotSelectionCriteria(md.SequenceNr), long.MaxValue), _senderProbe.Ref);
+            _senderProbe.ExpectMsg<LoadSnapshotResult>(result =>
+                result.ToSequenceNr == long.MaxValue
+                && result.Snapshot != null
+                && result.Snapshot.Metadata.Equals(Metadata[1])
+                && result.Snapshot.Snapshot.ToString() == "s-2");
+        }
+
+        // Issue #7312, this is a side effect of the ctor signature changes
+        // DeleteSnapshot should not delete snapshot if timestamp value does not meet deletion criteria
+        [Fact]
+        public virtual void SnapshotStore_should_not_delete_snapshot_identified_by_SequenceNr_if_metadata_timestamp_is_less_than_stored_timestamp()
+        {
+            var md = Metadata[2];
+            // timestamp argument is less than the actual metadata data stored in the database, no deletion occured
+            md = new SnapshotMetadata(md.PersistenceId, md.SequenceNr, md.Timestamp - 2.Seconds());
+            var command = new DeleteSnapshot(md);
+            var sub = CreateTestProbe();
+
+            Subscribe<DeleteSnapshot>(sub.Ref);
+            SnapshotStore.Tell(command, _senderProbe.Ref);
+            sub.ExpectMsg(command);
+            _senderProbe.ExpectMsg<DeleteSnapshotSuccess>();
+
+            SnapshotStore.Tell(new LoadSnapshot(Pid, new SnapshotSelectionCriteria(md.SequenceNr), long.MaxValue), _senderProbe.Ref);
+            _senderProbe.ExpectMsg<LoadSnapshotResult>(result =>
+                result.ToSequenceNr == long.MaxValue
+                && result.Snapshot != null
+                && result.Snapshot.Metadata.Equals(Metadata[2])
+                && result.Snapshot.Snapshot.ToString() == "s-3");
+        }
+
         [Fact]
         public virtual void SnapshotStore_should_delete_all_snapshots_matching_upper_sequence_number_and_timestamp_bounds()
         {
@@ -260,7 +311,7 @@ public virtual void SnapshotStore_should_save_and_overwrite_snapshot_with_same_s
         [Fact]
         public virtual void SnapshotStore_should_save_bigger_size_snapshot()
         {
-            var metadata = new SnapshotMetadata(Pid, 100);
+            var metadata = new SnapshotMetadata(Pid, 100, Sys.Scheduler.Now.DateTime);
             var bigSnapshot = new byte[SnapshotByteSizeLimit];
             new Random().NextBytes(bigSnapshot);
             SnapshotStore.Tell(new SaveSnapshot(metadata, bigSnapshot), _senderProbe.Ref);
@@ -274,7 +325,7 @@ public virtual void ShouldSerializeSnapshots()
             if (!SupportsSerialization) return;
 
             var probe = CreateTestProbe();
-            var metadata = new SnapshotMetadata(Pid, 100L);
+            var metadata = new SnapshotMetadata(Pid, 100L, Sys.Scheduler.Now.DateTime);
             var snap = new TestPayload(probe.Ref);
 
             SnapshotStore.Tell(new SaveSnapshot(metadata, snap), _senderProbe.Ref);

src/core/Akka.Persistence/Eventsourced.cs

@@ -218,7 +218,7 @@ public void LoadSnapshot(string persistenceId, SnapshotSelectionCriteria criteri
         /// <param name="snapshot">TBD</param>
         public void SaveSnapshot(object snapshot)
         {
-            SnapshotStore.Tell(new SaveSnapshot(new SnapshotMetadata(SnapshotterId, SnapshotSequenceNr), snapshot));
+            SnapshotStore.Tell(new SaveSnapshot(new SnapshotMetadata(SnapshotterId, SnapshotSequenceNr, Context.System.Scheduler.Now.Date), snapshot));
         }
 
         /// <summary>
@@ -230,7 +230,7 @@ public void SaveSnapshot(object snapshot)
         /// <param name="sequenceNr">TBD</param>
         public void DeleteSnapshot(long sequenceNr)
         {
-            SnapshotStore.Tell(new DeleteSnapshot(new SnapshotMetadata(SnapshotterId, sequenceNr)));
+            SnapshotStore.Tell(new DeleteSnapshot(new SnapshotMetadata(SnapshotterId, sequenceNr, DateTime.MinValue)));
         }
 
         /// <summary>

src/core/Akka.Persistence/SnapshotProtocol.cs

@@ -52,32 +52,28 @@ public int Compare(SnapshotMetadata x, SnapshotMetadata y)
         }
 
         /// <summary>
-        /// TBD
+        /// The singleton comparer instance.
         /// </summary>
         public static IComparer<SnapshotMetadata> Comparer { get; } = new SnapshotMetadataComparer();
 
-        /// <summary>
-        /// TBD
-        /// </summary>
-        public static DateTime TimestampNotSpecified = DateTime.MinValue;
-
         /// <summary>
         /// Initializes a new instance of the <see cref="SnapshotMetadata"/> class.
         /// </summary>
         /// <param name="persistenceId">The id of the persistent actor fro which the snapshot was taken.</param>
         /// <param name="sequenceNr">The sequence number at which the snapshot was taken.</param>
+        [Obsolete("This constructor is deprecated and will be removed in v1.6. Use the constructor with the timestamp parameter instead. Since v1.5.28", true)]
         public SnapshotMetadata(string persistenceId, long sequenceNr)
-            : this(persistenceId, sequenceNr, TimestampNotSpecified)
+            : this(persistenceId, sequenceNr, DateTime.UtcNow)
         {
         }
 
         /// <summary>
         /// Initializes a new instance of the <see cref="SnapshotMetadata"/> class.
         /// </summary>
-        /// <param name="persistenceId">The id of the persistent actor fro mwhich the snapshot was taken.</param>
+        /// <param name="persistenceId">The id of the persistent actor from which the snapshot was taken.</param>
         /// <param name="sequenceNr">The sequence number at which the snapshot was taken.</param>
         /// <param name="timestamp">The time at which the snapshot was saved.</param>
-        [JsonConstructor]
+        [JsonConstructor] // TODO: remove this
         public SnapshotMetadata(string persistenceId, long sequenceNr, DateTime timestamp)
         {
             PersistenceId = persistenceId;
@@ -100,7 +96,13 @@ public SnapshotMetadata(string persistenceId, long sequenceNr, DateTime timestam
         /// </summary>
         public DateTime Timestamp { get; }
 
-
+        /// <summary>
+        /// We will probably use nullable in the future, but for the time being
+        /// we use <see cref="DateTime.MinValue"/> to represent "no timestamp"
+        /// </summary>
+        internal static DateTime TimestampNotSpecified => DateTime.MinValue;
+
+
         public override bool Equals(object obj) => Equals(obj as SnapshotMetadata);
 
 

src/core/Akka/Actor/Scheduler/SchedulerBase.cs

@@ -98,7 +98,7 @@ void IActionScheduler.ScheduleRepeatedly(TimeSpan initialDelay, TimeSpan interva
         DateTimeOffset ITimeProvider.Now { get { return TimeNow; } }
 
         /// <summary>
-        /// TBD
+        /// The current time in UTC.
         /// </summary>
         protected abstract DateTimeOffset TimeNow { get; }