From 9dbc5ede7510775ab9fc9d96b61e486089efd04f Mon Sep 17 00:00:00 2001
From: Sina Darbouy <sinadarbouy@gmail.com>
Date: Tue, 16 Jun 2026 15:31:52 +0200
Subject: [PATCH] fix: register MongoDB AWS authentication for Atlas IAM
 (driver 3.x) (#1324)

MongoDB.Driver 3.x moved MONGODB-AWS into MongoDB.Driver.Authentication.AWS
and requires explicit registration. Without it, Atlas IAM connection strings
fail at startup with "Unable to create an authenticator".

Co-authored-by: Cursor <cursoragent@cursor.com>
---
 backend/src/Squidex.Data.MongoDb/MongoClientFactory.cs    | 8 ++++++++
 .../src/Squidex.Data.MongoDb/Squidex.Data.MongoDb.csproj  | 1 +
 2 files changed, 9 insertions(+)

diff --git a/backend/src/Squidex.Data.MongoDb/MongoClientFactory.cs b/backend/src/Squidex.Data.MongoDb/MongoClientFactory.cs
index 2ae3301c4..586f8f323 100644
--- a/backend/src/Squidex.Data.MongoDb/MongoClientFactory.cs
+++ b/backend/src/Squidex.Data.MongoDb/MongoClientFactory.cs
@@ -8,6 +8,7 @@
 using System.Text.Json;
 using MongoDB.Bson;
 using MongoDB.Driver;
+using MongoDB.Driver.Authentication.AWS;
 using Squidex.Domain.Apps.Core.Contents;
 using Squidex.Domain.Apps.Entities;
 using Squidex.Domain.Apps.Entities.Assets;
@@ -23,6 +24,8 @@ namespace Squidex;
 
 public static class MongoClientFactory
 {
+    private static int awsAuthenticationRegistered;
+
     public static void SetupSerializer(JsonSerializerOptions jsonSerializerOptions, BsonType representation)
     {
         // Register the serializers first.
@@ -53,6 +56,11 @@ public static class MongoClientFactory
 
     public static MongoClient Create(string? connectionString, Action<MongoClientSettings>? configure = null)
     {
+        if (Interlocked.Exchange(ref awsAuthenticationRegistered, 1) == 0)
+        {
+            MongoClientSettings.Extensions.AddAWSAuthentication();
+        }
+
         var clientSettings = MongoClientSettings.FromConnectionString(connectionString);
 
         // If we really need custom config.
diff --git a/backend/src/Squidex.Data.MongoDb/Squidex.Data.MongoDb.csproj b/backend/src/Squidex.Data.MongoDb/Squidex.Data.MongoDb.csproj
index 6e32dfbfe..9504e6a67 100644
--- a/backend/src/Squidex.Data.MongoDb/Squidex.Data.MongoDb.csproj
+++ b/backend/src/Squidex.Data.MongoDb/Squidex.Data.MongoDb.csproj
@@ -21,6 +21,7 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
     <PackageReference Include="MongoDB.Driver" Version="3.8.0" />
+    <PackageReference Include="MongoDB.Driver.Authentication.AWS" Version="3.8.0" />
     <PackageReference Include="MongoDB.Driver.Core.Extensions.DiagnosticSources" Version="3.0.0" />
     <PackageReference Include="NodaTime.Serialization.SystemTextJson" Version="1.3.1" />
     <PackageReference Include="RefactoringEssentials" Version="5.6.0" PrivateAssets="all" />