infrastructure for dealing with client cache invalidation in a multi-user environment

Oqtane.Server/Infrastructure/SyncManager.cs

@@ -0,0 +1,44 @@
+using Microsoft.Extensions.DependencyInjection;
+using Oqtane.Models;
+using Oqtane.Repository;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace Oqtane.Infrastructure
+{
+    public class SyncManager : ISyncManager
+    {
+        private readonly IServiceScopeFactory ServiceScopeFactory;
+        private List<SyncEvent> SyncEvents { get; set; }
+
+        public SyncManager(IServiceScopeFactory ServiceScopeFactory)
+        {
+            this.ServiceScopeFactory = ServiceScopeFactory;
+            SyncEvents = new List<SyncEvent>();
+        }
+
+        private int TenantId
+        {
+            get 
+            {
+                using (var scope = ServiceScopeFactory.CreateScope())
+                {
+                    return scope.ServiceProvider.GetRequiredService<ITenantResolver>().GetTenant().TenantId;
+                }
+            }
+        }
+
+        public List<SyncEvent> GetSyncEvents(DateTime LastSyncDate)
+        {
+            return SyncEvents.Where(item => item.TenantId == TenantId && item.ModifiedOn >= LastSyncDate).ToList();
+        }
+
+        public void AddSyncEvent(string EntityName, int EntityId)
+        {
+            SyncEvents.Add(new SyncEvent { TenantId = TenantId, EntityName = EntityName, EntityId = EntityId, ModifiedOn = DateTime.Now });
+            // trim sync events 
+            SyncEvents.RemoveAll(item => item.ModifiedOn < DateTime.Now.AddHours(-1));
+        }
+    }
+}