Fix job scheduler race condition and enhance Blazor reconnection UI

DiunaBI.Infrastructure/Services/JobSchedulerService.cs

@@ -40,6 +40,7 @@ public class JobSchedulerService
         _logger.LogInformation("JobScheduler: Found {Count} import workers to schedule", importWorkers.Count);
 
         var jobsCreated = 0;
+        var scheduledLayerIds = new HashSet<Guid>(); // Track LayerIds scheduled in this batch
 
         foreach (var worker in importWorkers)
         {
@@ -61,7 +62,15 @@ public class JobSchedulerService
                 var maxRetriesStr = worker.Records?.FirstOrDefault(r => r.Code == "MaxRetries")?.Desc1;
                 var maxRetries = int.TryParse(maxRetriesStr, out var mr) ? mr : 3;
 
-                // Check if there's already a pending/running job for this layer
+                // Check in-memory: already scheduled in this batch?
+                if (scheduledLayerIds.Contains(worker.Id))
+                {
+                    _logger.LogDebug("JobScheduler: Job already scheduled in this batch for {LayerName} ({LayerId})",
+                        worker.Name, worker.Id);
+                    continue;
+                }
+
+                // Check if there's already a pending/running job for this layer in database
                 var existingJob = await _db.QueueJobs
                     .Where(j => j.LayerId == worker.Id &&
                                 (j.Status == JobStatus.Pending || j.Status == JobStatus.Running))
@@ -91,6 +100,7 @@ public class JobSchedulerService
                 };
 
                 _db.QueueJobs.Add(job);
+                scheduledLayerIds.Add(worker.Id); // Track that we've scheduled this layer
                 jobsCreated++;
 
                 _logger.LogInformation("JobScheduler: Created import job for {LayerName} ({LayerId}) with priority {Priority}",
@@ -129,6 +139,7 @@ public class JobSchedulerService
         _logger.LogInformation("JobScheduler: Found {Count} process workers to schedule", processWorkers.Count);
 
         var jobsCreated = 0;
+        var scheduledLayerIds = new HashSet<Guid>(); // Track LayerIds scheduled in this batch
 
         foreach (var worker in processWorkers)
         {
@@ -150,7 +161,15 @@ public class JobSchedulerService
                 var maxRetriesStr = worker.Records?.FirstOrDefault(r => r.Code == "MaxRetries")?.Desc1;
                 var maxRetries = int.TryParse(maxRetriesStr, out var mr) ? mr : 3;
 
-                // Check if there's already a pending/running job for this layer
+                // Check in-memory: already scheduled in this batch?
+                if (scheduledLayerIds.Contains(worker.Id))
+                {
+                    _logger.LogDebug("JobScheduler: Job already scheduled in this batch for {LayerName} ({LayerId})",
+                        worker.Name, worker.Id);
+                    continue;
+                }
+
+                // Check if there's already a pending/running job for this layer in database
                 var existingJob = await _db.QueueJobs
                     .Where(j => j.LayerId == worker.Id &&
                                 (j.Status == JobStatus.Pending || j.Status == JobStatus.Running))
@@ -180,6 +199,7 @@ public class JobSchedulerService
                 };
 
                 _db.QueueJobs.Add(job);
+                scheduledLayerIds.Add(worker.Id); // Track that we've scheduled this layer
                 jobsCreated++;
 
                 _logger.LogInformation("JobScheduler: Created process job for {LayerName} ({LayerId}) with priority {Priority}",