refactored IBsonSerializer to not be aware of identities instead opting for a more granular interface such that implementors of IBsonSerializer don't need to implement methods they don't use.

Author: craiggwilson

Bson/Bson.csproj

@@ -104,6 +104,7 @@
     <Compile Include="Serialization\Conventions\SerializationOptionsConventions.cs" />
     <Compile Include="Serialization\IBsonClassMapModifier.cs" />
     <Compile Include="Serialization\IBsonMemberMapModifier.cs" />
+    <Compile Include="Serialization\IBsonIdProvider.cs" />
     <Compile Include="Serialization\Options\ArraySerializationOptions.cs" />
     <Compile Include="Serialization\Options\BsonBaseSerializationOptions.cs" />
     <Compile Include="Serialization\Options\DateTimeSerializationOptions.cs" />

Bson/Serialization/BsonClassMapSerializer.cs

@@ -30,7 +30,7 @@ namespace MongoDB.Bson.Serialization
     /// <summary>
     /// Represents a serializer for a class map.
     /// </summary>
-    public class BsonClassMapSerializer : IBsonSerializer
+    internal class BsonClassMapSerializer : IBsonSerializer, IBsonIdProvider
     {
         // private fields
         private BsonClassMap _classMap;

Bson/Serialization/IBsonIdProvider.cs

@@ -0,0 +1,30 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace MongoDB.Bson.Serialization
+{
+    /// <summary>
+    /// Contract for serializers that can get and set identities.
+    /// </summary>
+    public interface IBsonIdProvider
+    {
+        /// <summary>
+        /// Gets the document Id.
+        /// </summary>
+        /// <param name="document">The document.</param>
+        /// <param name="id">The Id.</param>
+        /// <param name="idNominalType">The nominal type of the Id.</param>
+        /// <param name="idGenerator">The IdGenerator for the Id type.</param>
+        /// <returns>True if the document has an Id.</returns>
+        bool GetDocumentId(object document, out object id, out Type idNominalType, out IIdGenerator idGenerator);
+
+        /// <summary>
+        /// Sets the document Id.
+        /// </summary>
+        /// <param name="document">The document.</param>
+        /// <param name="id">The Id.</param>
+        void SetDocumentId(object document, object id);
+    }
+}

Bson/Serialization/IBsonSerializer.cs

@@ -47,15 +47,6 @@ public interface IBsonSerializer
         /// <returns>The default serialization options for this serializer.</returns>
         IBsonSerializationOptions GetDefaultSerializationOptions();
         /// <summary>
-        /// Gets the document Id.
-        /// </summary>
-        /// <param name="document">The document.</param>
-        /// <param name="id">The Id.</param>
-        /// <param name="idNominalType">The nominal type of the Id.</param>
-        /// <param name="idGenerator">The IdGenerator for the Id type.</param>
-        /// <returns>True if the document has an Id.</returns>
-        bool GetDocumentId(object document, out object id, out Type idNominalType, out IIdGenerator idGenerator);
-        /// <summary>
         /// Gets the serialization info for individual items of an enumerable type.
         /// </summary>
         /// <returns>The serialization info for the items.</returns>
@@ -74,11 +65,5 @@ public interface IBsonSerializer
         /// <param name="value">The object.</param>
         /// <param name="options">The serialization options.</param>
         void Serialize(BsonWriter bsonWriter, Type nominalType, object value, IBsonSerializationOptions options);
-        /// <summary>
-        /// Sets the document Id.
-        /// </summary>
-        /// <param name="document">The document.</param>
-        /// <param name="id">The Id.</param>
-        void SetDocumentId(object document, object id);
     }
 }

Bson/Serialization/Serializers/BsonBaseSerializer.cs

@@ -103,23 +103,6 @@ public virtual IBsonSerializationOptions GetDefaultSerializationOptions()
             return _defaultSerializationOptions;
         }
 
-        /// <summary>
-        /// Gets the document Id.
-        /// </summary>
-        /// <param name="document">The document.</param>
-        /// <param name="id">The Id.</param>
-        /// <param name="idNominalType">The nominal type of the Id.</param>
-        /// <param name="idGenerator">The IdGenerator for the Id type.</param>
-        /// <returns>True if the document has an Id.</returns>
-        public virtual bool GetDocumentId(
-            object document,
-            out object id,
-            out Type idNominalType,
-            out IIdGenerator idGenerator)
-        {
-            throw new NotSupportedException("Subclass must implement GetDocumentId.");
-        }
-
         /// <summary>
         /// Gets the serialization info for individual items of an enumerable type.
         /// </summary>
@@ -157,16 +140,6 @@ public virtual void Serialize(
             throw new NotSupportedException("Subclass must implement Serialize.");
         }
 
-        /// <summary>
-        /// Sets the document Id.
-        /// </summary>
-        /// <param name="document">The document.</param>
-        /// <param name="id">The Id.</param>
-        public virtual void SetDocumentId(object document, object id)
-        {
-            throw new NotSupportedException("Subclass must implement SetDocumentId.");
-        }
-
         // protected methods
         /// <summary>
         /// Ensures that the serializer has serialization options of the right type (replacing null with the default serialization options if necessary).

Bson/Serialization/Serializers/BsonIBsonSerializableSerializer.cs

@@ -28,7 +28,7 @@ namespace MongoDB.Bson.Serialization.Serializers
     /// <summary>
     /// Represents a serializer for classes that implement IBsonSerializable.
     /// </summary>
-    public class BsonIBsonSerializableSerializer : IBsonSerializer
+    public class BsonIBsonSerializableSerializer : IBsonSerializer, IBsonIdProvider
     {
         // private static fields
         private static BsonIBsonSerializableSerializer __instance = new BsonIBsonSerializableSerializer();

Bson/Serialization/Serializers/BsonValueSerializers.cs

@@ -543,7 +543,7 @@ public override void Serialize(
     /// <summary>
     /// Represents a serializer for BsonDocuments.
     /// </summary>
-    public class BsonDocumentSerializer : BsonBaseSerializer
+    public class BsonDocumentSerializer : BsonBaseSerializer, IBsonIdProvider
     {
         // private static fields
         private static BsonDocumentSerializer __instance = new BsonDocumentSerializer();
@@ -594,7 +594,7 @@ public override object Deserialize(
         /// <param name="idNominalType">The nominal type of the Id.</param>
         /// <param name="idGenerator">The IdGenerator for the Id type.</param>
         /// <returns>True if the document has an Id.</returns>
-        public override bool GetDocumentId(
+        public bool GetDocumentId(
             object document,
             out object id,
             out Type idNominalType,
@@ -633,7 +633,7 @@ public override void Serialize(
         /// </summary>
         /// <param name="document">The document.</param>
         /// <param name="id">The Id.</param>
-        public override void SetDocumentId(object document, object id)
+        public void SetDocumentId(object document, object id)
         {
             var bsonDocument = (BsonDocument)document;
             ((IBsonSerializable)bsonDocument).SetDocumentId(id);

Bson/Serialization/Serializers/ObjectSerializer.cs

@@ -155,23 +155,6 @@ public IBsonSerializationOptions GetDefaultSerializationOptions()
             return null;
         }
 
-        /// <summary>
-        /// Gets the document Id.
-        /// </summary>
-        /// <param name="document">The document.</param>
-        /// <param name="id">The Id.</param>
-        /// <param name="idNominalType">The nominal type of the Id.</param>
-        /// <param name="idGenerator">The IdGenerator for the Id type.</param>
-        /// <returns>True if the document has an Id.</returns>
-        public bool GetDocumentId(
-           object document,
-           out object id,
-           out Type idNominalType,
-           out IIdGenerator idGenerator)
-        {
-            throw new NotSupportedException();
-        }
-
         /// <summary>
         /// Gets the serialization info for individual items of an enumerable type.
         /// </summary>
@@ -221,15 +204,5 @@ public void Serialize(
                 bsonWriter.WriteEndDocument();
             }
         }
-
-        /// <summary>
-        /// Sets the document Id.
-        /// </summary>
-        /// <param name="document">The document.</param>
-        /// <param name="id">The Id.</param>
-        public void SetDocumentId(object document, object id)
-        {
-            throw new NotSupportedException();
-        }
     }
 }

BsonUnitTests/Jira/CSharp81Tests.cs

@@ -52,13 +52,13 @@ public void TestIdMember()
             var idMemberMap = classMap.IdMemberMap;
             Assert.AreEqual("Id", idMemberMap.MemberName);
 
-            var serializer = BsonSerializer.LookupSerializer(typeof(User));
+            var identityProvider = BsonSerializer.LookupSerializer(typeof(User)) as IBsonIdProvider;
             var idGenerator = BsonSerializer.LookupIdGenerator(typeof(ObjectId));
-            serializer.SetDocumentId(u, idGenerator.GenerateId(null, u));
+            identityProvider.SetDocumentId(u, idGenerator.GenerateId(null, u));
             Assert.IsFalse(idGenerator.IsEmpty(u.Id));
             Assert.IsTrue(idGenerator.IsEmpty(u.FriendId));
 
             var json = u.ToJson();
         }
     }
-}
+}

Driver/Core/MongoCollection.cs

@@ -1075,18 +1075,23 @@ public virtual IEnumerable<SafeModeResult> InsertBatch(
                         {
                             throw new ArgumentException("Batch contains one or more null documents.");
                         }
+
                         if (_settings.AssignIdOnInsert)
                         {
                             var serializer = BsonSerializer.LookupSerializer(document.GetType());
-                            object id;
-                            Type idNominalType;
-                            IIdGenerator idGenerator;
-                            if (serializer.GetDocumentId(document, out id, out idNominalType, out idGenerator))
+                            var identityProvider = serializer as IBsonIdProvider;
+                            if (identityProvider != null)
                             {
-                                if (idGenerator != null && idGenerator.IsEmpty(id))
+                                object id;
+                                Type idNominalType;
+                                IIdGenerator idGenerator;
+                                if (identityProvider.GetDocumentId(document, out id, out idNominalType, out idGenerator))
                                 {
-                                    id = idGenerator.GenerateId(this, document);
-                                    serializer.SetDocumentId(document, id);
+                                    if (idGenerator != null && idGenerator.IsEmpty(id))
+                                    {
+                                        id = idGenerator.GenerateId(this, document);
+                                        identityProvider.SetDocumentId(document, id);
+                                    }
                                 }
                             }
                         }
@@ -1351,10 +1356,11 @@ public virtual SafeModeResult Save(Type nominalType, object document, MongoInser
                 throw new ArgumentNullException("document");
             }
             var serializer = BsonSerializer.LookupSerializer(document.GetType());
+            var identityProvider = serializer as IBsonIdProvider;
             object id;
             Type idNominalType;
             IIdGenerator idGenerator;
-            if (serializer.GetDocumentId(document, out id, out idNominalType, out idGenerator))
+            if (identityProvider != null && identityProvider.GetDocumentId(document, out id, out idNominalType, out idGenerator))
             {
                 if (id == null && idGenerator == null)
                 {
@@ -1364,7 +1370,7 @@ public virtual SafeModeResult Save(Type nominalType, object document, MongoInser
                 if (idGenerator != null && idGenerator.IsEmpty(id))
                 {
                     id = idGenerator.GenerateId(this, document);
-                    serializer.SetDocumentId(document, id);
+                    identityProvider.SetDocumentId(document, id);
                     return Insert(nominalType, document, options);
                 }
                 else