From 196f0a0a178eae9d53bdeb2f08fdbe91c9350792 Mon Sep 17 00:00:00 2001
From: meysamhadeli <meysamhadeli@gmail.com>
Date: Sun, 29 Jan 2023 22:28:29 +0330
Subject: [PATCH 1/2] refactor: Refactor PersistMessageProcessor with locking

---
 .../Data/PersistMessageDbContext.cs               | 14 +++++++-------
 .../PersistMessageProcessor.cs                    | 15 ++++++++++++++-
 2 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/src/BuildingBlocks/PersistMessageProcessor/Data/PersistMessageDbContext.cs b/src/BuildingBlocks/PersistMessageProcessor/Data/PersistMessageDbContext.cs
index 9972b7d..fe57458 100644
--- a/src/BuildingBlocks/PersistMessageProcessor/Data/PersistMessageDbContext.cs
+++ b/src/BuildingBlocks/PersistMessageProcessor/Data/PersistMessageDbContext.cs
@@ -58,16 +58,16 @@ public class PersistMessageDbContext : DbContext, IPersistMessageDbContext
         {
             foreach (var entry in ex.Entries)
             {
-                var currentValues = entry.CurrentValues;
                 var databaseValues = await entry.GetDatabaseValuesAsync(cancellationToken);
 
-                _logger.LogInformation(
-                    "Entry to entity with database-value: {@databaseValues} and current-value: {@currentValues}",
-                    databaseValues,
-                    currentValues);
+                if (databaseValues == null)
+                {
+                    _logger.LogError("The record no longer exists in the database, The record has been deleted by another user.");
+                    throw;
+                }
 
-                // Refresh the original values with current values
-                entry.OriginalValues.SetValues(currentValues);
+                // Refresh the original values to bypass next concurrency check
+                entry.OriginalValues.SetValues(databaseValues);
             }
 
             return await base.SaveChangesAsync(cancellationToken);
diff --git a/src/BuildingBlocks/PersistMessageProcessor/PersistMessageProcessor.cs b/src/BuildingBlocks/PersistMessageProcessor/PersistMessageProcessor.cs
index 8dc5c6e..ce2c8eb 100644
--- a/src/BuildingBlocks/PersistMessageProcessor/PersistMessageProcessor.cs
+++ b/src/BuildingBlocks/PersistMessageProcessor/PersistMessageProcessor.cs
@@ -18,6 +18,7 @@ public class PersistMessageProcessor : IPersistMessageProcessor
     private readonly IMediator _mediator;
     private readonly IPersistMessageDbContext _persistMessageDbContext;
     private readonly IPublishEndpoint _publishEndpoint;
+    private static SemaphoreSlim Semaphore => new SemaphoreSlim(initialCount: 0, maxCount: 1);
 
     public PersistMessageProcessor(
         ILogger<PersistMessageProcessor> logger,
@@ -115,7 +116,19 @@ public class PersistMessageProcessor : IPersistMessageProcessor
             .Where(x => x.MessageStatus != MessageStatus.Processed)
             .ToListAsync(cancellationToken);
 
-        foreach (var message in messages) await ProcessAsync(message.Id, message.DeliveryType, cancellationToken);
+        foreach (var message in messages)
+        {
+            await Semaphore.WaitAsync(cancellationToken);
+
+            try
+            {
+                await ProcessAsync(message.Id, message.DeliveryType, cancellationToken);
+            }
+            finally
+            {
+                Semaphore.Release();
+            }
+        }
     }
 
     public async Task ProcessInboxAsync(long messageId, CancellationToken cancellationToken = default)

From a6957c272ccdfb60bdbbc3366ae892876cdb733d Mon Sep 17 00:00:00 2001
From: meysamhadeli <meysamhadeli@gmail.com>
Date: Sun, 29 Jan 2023 22:47:15 +0330
Subject: [PATCH 2/2] Update PersistMessageProcessor

---
 .../PersistMessageProcessor/PersistMessageProcessor.cs          | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/BuildingBlocks/PersistMessageProcessor/PersistMessageProcessor.cs b/src/BuildingBlocks/PersistMessageProcessor/PersistMessageProcessor.cs
index ce2c8eb..674a438 100644
--- a/src/BuildingBlocks/PersistMessageProcessor/PersistMessageProcessor.cs
+++ b/src/BuildingBlocks/PersistMessageProcessor/PersistMessageProcessor.cs
@@ -18,7 +18,7 @@ public class PersistMessageProcessor : IPersistMessageProcessor
     private readonly IMediator _mediator;
     private readonly IPersistMessageDbContext _persistMessageDbContext;
     private readonly IPublishEndpoint _publishEndpoint;
-    private static SemaphoreSlim Semaphore => new SemaphoreSlim(initialCount: 0, maxCount: 1);
+    private SemaphoreSlim Semaphore => new SemaphoreSlim(1);
 
     public PersistMessageProcessor(
         ILogger<PersistMessageProcessor> logger,