save progress

src/Scheduler/__Libraries/StellaOps.Scheduler.Queue/Nats/NatsSchedulerQueueBase.cs

@@ -9,6 +9,7 @@ using Microsoft.Extensions.Logging;
 using NATS.Client.Core;
 using NATS.Client.JetStream;
 using NATS.Client.JetStream.Models;
+using StellaOps.HybridLogicalClock;
 
 namespace StellaOps.Scheduler.Queue.Nats;
 
@@ -24,6 +25,7 @@ internal abstract class NatsSchedulerQueueBase<TMessage> : ISchedulerQueue<TMess
     private readonly INatsSchedulerQueuePayload<TMessage> _payload;
     private readonly ILogger _logger;
     private readonly TimeProvider _timeProvider;
+    private readonly IHybridLogicalClock? _hlc;
     private readonly SemaphoreSlim _connectionGate = new(1, 1);
     private readonly Func<NatsOpts, CancellationToken, ValueTask<NatsConnection>> _connectionFactory;
 
@@ -40,6 +42,7 @@ internal abstract class NatsSchedulerQueueBase<TMessage> : ISchedulerQueue<TMess
         INatsSchedulerQueuePayload<TMessage> payload,
         ILogger logger,
         TimeProvider timeProvider,
+        IHybridLogicalClock? hlc = null,
         Func<NatsOpts, CancellationToken, ValueTask<NatsConnection>>? connectionFactory = null)
     {
         _queueOptions = queueOptions ?? throw new ArgumentNullException(nameof(queueOptions));
@@ -48,6 +51,7 @@ internal abstract class NatsSchedulerQueueBase<TMessage> : ISchedulerQueue<TMess
         _payload = payload ?? throw new ArgumentNullException(nameof(payload));
         _logger = logger ?? throw new ArgumentNullException(nameof(logger));
         _timeProvider = timeProvider ?? TimeProvider.System;
+        _hlc = hlc;
         _connectionFactory = connectionFactory ?? ((opts, cancellationToken) => new ValueTask<NatsConnection>(new NatsConnection(opts)));
 
         if (string.IsNullOrWhiteSpace(_natsOptions.Url))
@@ -67,7 +71,11 @@ internal abstract class NatsSchedulerQueueBase<TMessage> : ISchedulerQueue<TMess
 
         var payloadBytes = _payload.Serialize(message);
         var idempotencyKey = _payload.GetIdempotencyKey(message);
-        var headers = BuildHeaders(message, idempotencyKey);
+
+        // Generate HLC timestamp if clock is available
+        var hlcTimestamp = _hlc?.Tick();
+
+        var headers = BuildHeaders(message, idempotencyKey, hlcTimestamp);
 
         var publishOptions = new NatsJSPubOpts
         {
@@ -531,6 +539,14 @@ internal abstract class NatsSchedulerQueueBase<TMessage> : ISchedulerQueue<TMess
             ? DateTimeOffset.FromUnixTimeMilliseconds(unix)
             : now;
 
+        // Parse HLC timestamp if present
+        HlcTimestamp? hlcTimestamp = null;
+        if (headers.TryGetValue(SchedulerQueueFields.HlcTimestamp, out var hlcValues) && hlcValues.Count > 0
+            && HlcTimestamp.TryParse(hlcValues[0], out var parsedHlc))
+        {
+            hlcTimestamp = parsedHlc;
+        }
+
         var leaseExpires = now.Add(leaseDuration);
         var runId = _payload.GetRunId(deserialized);
         var tenantId = _payload.GetTenantId(deserialized);
@@ -558,10 +574,11 @@ internal abstract class NatsSchedulerQueueBase<TMessage> : ISchedulerQueue<TMess
             attempt,
             enqueuedAt,
             leaseExpires,
-            consumer);
+            consumer,
+            hlcTimestamp);
     }
 
-    private NatsHeaders BuildHeaders(TMessage message, string idempotencyKey)
+    private NatsHeaders BuildHeaders(TMessage message, string idempotencyKey, HlcTimestamp? hlcTimestamp = null)
     {
         var headers = new NatsHeaders
         {
@@ -572,6 +589,12 @@ internal abstract class NatsSchedulerQueueBase<TMessage> : ISchedulerQueue<TMess
             { SchedulerQueueFields.EnqueuedAt, _timeProvider.GetUtcNow().ToUnixTimeMilliseconds().ToString() }
         };
 
+        // Include HLC timestamp if available
+        if (hlcTimestamp.HasValue)
+        {
+            headers.Add(SchedulerQueueFields.HlcTimestamp, hlcTimestamp.Value.ToSortableString());
+        }
+
         var scheduleId = _payload.GetScheduleId(message);
         if (!string.IsNullOrWhiteSpace(scheduleId))
         {