Add IMongoClient constructor support to MongoDbContext for .NET Aspire integration

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "8.0.402",
+    "version": "8.0.117",
     "rollForward": "latestFeature"
   }
 }

src/Context.Tests/MongoDbContextTests.cs

@@ -98,6 +98,110 @@ public void Constructor_MongoOptions_CanAccessWhenNotInitialize()
 
         #endregion
 
+        #region IMongoClient Constructor Tests
+
+        [Fact]
+        public void Constructor_WithIMongoClient_AutoInitialize_InitializationExecuted()
+        {
+            // Arrange
+            var mongoClient = new MongoClient(_mongoOptions.ConnectionString);
+            var databaseName = _mongoDatabase.DatabaseNamespace.DatabaseName;
+
+            // Act
+            var testMongoDbContext = new TestMongoDbContextWithClient(mongoClient, databaseName);
+
+            // Assert
+            Assert.True(testMongoDbContext.IsInitialized);
+            Assert.Equal(mongoClient, testMongoDbContext.Client);
+            Assert.Equal(databaseName, testMongoDbContext.Database.DatabaseNamespace.DatabaseName);
+        }
+
+        [Fact]
+        public void Constructor_WithIMongoClient_NoInitialize_InitializationNotExecuted()
+        {
+            // Arrange
+            var mongoClient = new MongoClient(_mongoOptions.ConnectionString);
+            var databaseName = _mongoDatabase.DatabaseNamespace.DatabaseName;
+
+            // Act
+            var testMongoDbContext = new TestMongoDbContextWithClient(mongoClient, databaseName, false);
+
+            // Assert
+            Assert.False(testMongoDbContext.IsInitialized);
+        }
+
+        [Fact]
+        public void Constructor_WithIMongoClient_NullClient_ThrowsArgumentNullException()
+        {
+            // Arrange
+            IMongoClient mongoClient = null!;
+            var databaseName = _mongoDatabase.DatabaseNamespace.DatabaseName;
+
+            // Act & Assert
+            Assert.Throws<ArgumentNullException>(() => new TestMongoDbContextWithClient(mongoClient, databaseName));
+        }
+
+        [Fact]
+        public void Constructor_WithIMongoClient_NullDatabaseName_ThrowsArgumentNullException()
+        {
+            // Arrange
+            var mongoClient = new MongoClient(_mongoOptions.ConnectionString);
+            string databaseName = null!;
+
+            // Act & Assert
+            Assert.Throws<ArgumentNullException>(() => new TestMongoDbContextWithClient(mongoClient, databaseName));
+        }
+
+        [Fact]
+        public void Constructor_WithIMongoClient_Database_AccessibleAfterInitialize()
+        {
+            // Arrange
+            var mongoClient = new MongoClient(_mongoOptions.ConnectionString);
+            var databaseName = _mongoDatabase.DatabaseNamespace.DatabaseName;
+            var testMongoDbContext = new TestMongoDbContextWithClient(mongoClient, databaseName, false);
+
+            // Act
+            testMongoDbContext.Initialize();
+
+            // Assert
+            Assert.NotNull(testMongoDbContext.Database);
+            Assert.Equal(databaseName, testMongoDbContext.Database.DatabaseNamespace.DatabaseName);
+        }
+
+        [Fact]
+        public void Constructor_WithIMongoClient_CreateCollection_WorksAfterInitialize()
+        {
+            // Arrange
+            var mongoClient = new MongoClient(_mongoOptions.ConnectionString);
+            var databaseName = _mongoDatabase.DatabaseNamespace.DatabaseName;
+            var testMongoDbContext = new TestMongoDbContextWithClient(mongoClient, databaseName, false);
+
+            // Act
+            testMongoDbContext.Initialize();
+            var collection = testMongoDbContext.CreateCollection<BsonDocument>();
+
+            // Assert
+            Assert.NotNull(collection);
+        }
+
+        [Fact]
+        public void Constructor_WithIMongoClient_MongoOptions_IsConfiguredCorrectly()
+        {
+            // Arrange
+            var mongoClient = new MongoClient(_mongoOptions.ConnectionString);
+            var databaseName = _mongoDatabase.DatabaseNamespace.DatabaseName;
+
+            // Act
+            var testMongoDbContext = new TestMongoDbContextWithClient(mongoClient, databaseName);
+
+            // Assert
+            Assert.NotNull(testMongoDbContext.MongoOptions);
+            Assert.Equal(databaseName, testMongoDbContext.MongoOptions.DatabaseName);
+            Assert.Equal("", testMongoDbContext.MongoOptions.ConnectionString); // Empty for IMongoClient path
+        }
+
+        #endregion
+
         #region Private Helpers
 
         private class TestMongoDbContext : MongoDbContext
@@ -119,6 +223,26 @@ protected override void OnConfiguring(IMongoDatabaseBuilder mongoDatabaseBuilder
             public bool IsInitialized { get; private set; }
         }
 
+        private class TestMongoDbContextWithClient : MongoDbContext
+        {
+            public TestMongoDbContextWithClient(IMongoClient mongoClient, string databaseName) 
+                : base(mongoClient, databaseName)
+            {
+            }
+
+            public TestMongoDbContextWithClient(IMongoClient mongoClient, string databaseName, bool enableAutoInit)
+                : base(mongoClient, databaseName, enableAutoInit)
+            {
+            }
+
+            protected override void OnConfiguring(IMongoDatabaseBuilder mongoDatabaseBuilder)
+            {
+                IsInitialized = true;
+            }
+
+            public bool IsInitialized { get; private set; }
+        }
+
         #endregion
     }
 }

src/Context/Internal/MongoDatabaseBuilder.cs

@@ -14,7 +14,9 @@ namespace MongoDB.Extensions.Context;
 
 internal class MongoDatabaseBuilder : IMongoDatabaseBuilder
 {
-    private readonly MongoOptions _mongoOptions;
+    private readonly MongoOptions? _mongoOptions;
+    private readonly IMongoClient? _existingMongoClient;
+    private readonly string? _databaseName;
     private readonly List<Action> _registrationConventionActions;
     private readonly List<Action> _registrationSerializerActions;
     private readonly List<Action<MongoClientSettings>> _mongoClientSettingsActions;
@@ -34,6 +36,20 @@ static MongoDatabaseBuilder()
     public MongoDatabaseBuilder(MongoOptions mongoOptions)
     {
         _mongoOptions = mongoOptions;
+        _existingMongoClient = null;
+        _databaseName = null;
+        _registrationConventionActions = new List<Action>();
+        _registrationSerializerActions = new List<Action>();
+        _mongoClientSettingsActions = new List<Action<MongoClientSettings>>();
+        _databaseConfigurationActions = new List<Action<IMongoDatabase>>();
+        _collectionActions = new List<Action<IMongoDatabase, IMongoCollections>>();
+    }
+
+    public MongoDatabaseBuilder(IMongoClient mongoClient, string databaseName)
+    {
+        _mongoOptions = null;
+        _existingMongoClient = mongoClient;
+        _databaseName = databaseName;
         _registrationConventionActions = new List<Action>();
         _registrationSerializerActions = new List<Action>();
         _mongoClientSettingsActions = new List<Action<MongoClientSettings>>();
@@ -44,13 +60,27 @@ public MongoDatabaseBuilder(MongoOptions mongoOptions)
     public IMongoDatabaseBuilder ConfigureConnection(
         Action<MongoClientSettings> mongoClientSettingsAction)
     {
+        if (_existingMongoClient != null)
+        {
+            // When using an existing IMongoClient, we cannot modify its settings
+            // This configuration will be ignored
+            return this;
+        }
+
         _mongoClientSettingsActions.Add(mongoClientSettingsAction);
         return this;
     }
 
     public IMongoDatabaseBuilder ConfigureClientSettings(
         Action<MongoClientSettings> mongoClientSettingsAction)
     {
+        if (_existingMongoClient != null)
+        {
+            // When using an existing IMongoClient, we cannot modify its settings
+            // This configuration will be ignored
+            return this;
+        }
+
         _mongoClientSettingsActions.Add(mongoClientSettingsAction);
         return this;
     }
@@ -196,24 +226,37 @@ internal MongoDbContextData Build()
             TryRegisterObjectSerializer();
         }
 
-        // create mongo client settings
-        var mongoClientSettings = MongoClientSettings
-            .FromConnectionString(_mongoOptions.ConnectionString);
-
-        // set default mongo client settings
-        mongoClientSettings = SetDefaultClientSettings(
-            mongoClientSettings);
-
-        // set specific mongo client settings
-        _mongoClientSettingsActions.ForEach(
-            settings => settings(mongoClientSettings));
-
-        // create mongo client
-        var mongoClient = new MongoClient(mongoClientSettings);
+        IMongoClient mongoClient;
+        IMongoDatabase mongoDatabase;
 
-        // create mongo database
-        IMongoDatabase mongoDatabase = mongoClient
-            .GetDatabase(_mongoOptions.DatabaseName);
+        if (_existingMongoClient != null)
+        {
+            // Use existing client path
+            mongoClient = _existingMongoClient;
+            mongoDatabase = mongoClient.GetDatabase(_databaseName!);
+        }
+        else
+        {
+            // Original MongoOptions path
+            // create mongo client settings
+            var mongoClientSettings = MongoClientSettings
+                .FromConnectionString(_mongoOptions!.ConnectionString);
+
+            // set default mongo client settings
+            mongoClientSettings = SetDefaultClientSettings(
+                mongoClientSettings);
+
+            // set specific mongo client settings
+            _mongoClientSettingsActions.ForEach(
+                settings => settings(mongoClientSettings));
+
+            // create mongo client
+            mongoClient = new MongoClient(mongoClientSettings);
+
+            // create mongo database
+            mongoDatabase = mongoClient
+                .GetDatabase(_mongoOptions.DatabaseName);
+        }
 
         // configure mongo database
         _databaseConfigurationActions.ForEach(

src/Context/MongoDbContext.cs

@@ -24,8 +24,34 @@ public MongoDbContext(MongoOptions mongoOptions, bool enableAutoInitialize)
             Initialize();
         }
     }
+
+    public MongoDbContext(IMongoClient mongoClient, string databaseName) : this(mongoClient, databaseName, true)
+    {
+    }
+
+    public MongoDbContext(IMongoClient mongoClient, string databaseName, bool enableAutoInitialize)
+    {
+        // Create a minimal MongoOptions for interface compliance
+        MongoOptions = new MongoOptions
+        {
+            ConnectionString = "", // Not used when client is provided
+            DatabaseName = databaseName
+        };
+
+        MongoClient = mongoClient ?? throw new ArgumentNullException(nameof(mongoClient));
+        DatabaseName = databaseName ?? throw new ArgumentNullException(nameof(databaseName));
+
+        if (enableAutoInitialize)
+        {
+            Initialize();
+        }
+    }
+
     public MongoOptions MongoOptions { get; }
 
+    protected IMongoClient? MongoClient { get; }
+    protected string? DatabaseName { get; }
+
     public IMongoClient Client
     {
         get
@@ -61,7 +87,18 @@ public virtual void Initialize()
             {
                 if (_mongoDbContextData == null)
                 {
-                    var mongoDatabaseBuilder = new MongoDatabaseBuilder(MongoOptions);
+                    MongoDatabaseBuilder mongoDatabaseBuilder;
+
+                    if (MongoClient != null && DatabaseName != null)
+                    {
+                        // Use existing IMongoClient path
+                        mongoDatabaseBuilder = new MongoDatabaseBuilder(MongoClient, DatabaseName);
+                    }
+                    else
+                    {
+                        // Use MongoOptions path
+                        mongoDatabaseBuilder = new MongoDatabaseBuilder(MongoOptions);
+                    }
 
                     OnConfiguring(mongoDatabaseBuilder);