CSHARP-4173: Update FLE 2 collection management. (#796)

CSHARP-4173: Update FLE 2 collection management.

Author: DmitryLukyanov

src/MongoDB.Driver.Core/Core/Operations/CreateCollectionOperation.cs

@@ -62,7 +62,7 @@ internal static IWriteOperation<BsonDocument> CreateEncryptedCreateCollectionOpe
             }
 
             CreateCollectionOperation CreateInnerCollectionOperation(string collectionName)
-                => new CreateCollectionOperation(new CollectionNamespace(collectionNamespace.DatabaseNamespace.DatabaseName, collectionName), messageEncoderSettings);
+                => new CreateCollectionOperation(new CollectionNamespace(collectionNamespace.DatabaseNamespace.DatabaseName, collectionName), messageEncoderSettings) { ClusteredIndex = new BsonDocument { { "key", new BsonDocument("_id", 1) }, { "unique", true } } };
         }
         #endregion
 

src/MongoDB.Driver.Core/Core/Operations/DropCollectionOperation.cs

@@ -48,10 +48,10 @@ internal static IWriteOperation<BsonDocument> CreateEncryptedDropCollectionOpera
             if (encryptedFields != null)
             {
                 return new CompositeWriteOperation<BsonDocument>(
-                    (mainOperation, IsMainOperation: true),
                     (CreateInnerDropOperation(EncryptedCollectionHelper.GetAdditionalCollectionName(encryptedFields, collectionNamespace, HelperCollectionForEncryption.Esc)), IsMainOperation: false),
                     (CreateInnerDropOperation(EncryptedCollectionHelper.GetAdditionalCollectionName(encryptedFields, collectionNamespace, HelperCollectionForEncryption.Ecc)), IsMainOperation: false),
-                    (CreateInnerDropOperation(EncryptedCollectionHelper.GetAdditionalCollectionName(encryptedFields, collectionNamespace, HelperCollectionForEncryption.Ecos)), IsMainOperation: false));
+                    (CreateInnerDropOperation(EncryptedCollectionHelper.GetAdditionalCollectionName(encryptedFields, collectionNamespace, HelperCollectionForEncryption.Ecos)), IsMainOperation: false),
+                    (mainOperation, IsMainOperation: true));
             }
             else
             {

tests/MongoDB.Driver.Core.Tests/Core/Operations/CreateCollectionOperationTests.cs

@@ -510,16 +510,18 @@ public void CreateEncryptedCreateCollectionOperationIfConfigured_should_return_e
                 operations[3],
                 _collectionNamespace,
                 encryptedFields,
-                isMainOperation: true);
+                isMainOperation: true,
+                withClusteredIndex: false);
             // __safeContent__
             AssertIndex(operations[4], _collectionNamespace, index: new BsonDocument("__safeContent__", 1));
 
-            void AssertCreateCollectionCommand((IWriteOperation<BsonDocument> Operation, bool IsMainOperation) operationInfo, CollectionNamespace collectionNamespace, BsonDocument encryptedFields, bool isMainOperation)
+            void AssertCreateCollectionCommand((IWriteOperation<BsonDocument> Operation, bool IsMainOperation) operationInfo, CollectionNamespace collectionNamespace, BsonDocument encryptedFields, bool isMainOperation, bool withClusteredIndex = true)
             {
                 var expectedResult = new BsonDocument
                 {
                     { "create", collectionNamespace.CollectionName },
-                    { "encryptedFields", encryptedFields, encryptedFields != null }
+                    { "encryptedFields", encryptedFields, encryptedFields != null },
+                    { "clusteredIndex", new BsonDocument { { "key" , new BsonDocument("_id", 1 ) }, { "unique", true } }, withClusteredIndex }
                 };
                 AssertCommand(operationInfo, isMainOperation, expectedResult);
             }

tests/MongoDB.Driver.Core.Tests/Core/Operations/DropCollectionOperationTests.cs

@@ -141,31 +141,32 @@ public void CreateEncryptedDropCollectionOperationIfConfigured_should_return_exp
 
             var operations = ((CompositeWriteOperation<BsonDocument>)subject)._operations<BsonDocument>();
 
-            // main
-            AssertDropCollectionCommand(
-                operations[0],
-                _collectionNamespace,
-                encryptedFields,
-                isMainOperation: true);
             // esc
             AssertDropCollectionCommand(
-                operations[1],
+                operations[0],
                 new CollectionNamespace(_collectionNamespace.DatabaseNamespace.DatabaseName, GetExpectedCollectionName(escCollectionStrElement)),
                 encryptedFields: null,
                 isMainOperation: false);
             // ecc
             AssertDropCollectionCommand(
-                operations[2],
+                operations[1],
                 new CollectionNamespace(_collectionNamespace.DatabaseNamespace.DatabaseName, GetExpectedCollectionName(eccCollectionStrElement)),
                 encryptedFields: null,
                 isMainOperation: false);
             // eco
             AssertDropCollectionCommand(
-                operations[3],
+                operations[2],
                 new CollectionNamespace(_collectionNamespace.DatabaseNamespace.DatabaseName, GetExpectedCollectionName(ecocCollectionStrElement)),
                 encryptedFields: null,
                 isMainOperation: false);
 
+            // main
+            AssertDropCollectionCommand(
+                operations[3],
+                _collectionNamespace,
+                encryptedFields,
+                isMainOperation: true);
+
             void AssertDropCollectionCommand((IWriteOperation<BsonDocument> Operation, bool IsMainOperation) operationInfo, CollectionNamespace collectionNamespace, BsonDocument encryptedFields, bool isMainOperation)
             {
                 operationInfo.IsMainOperation.Should().Be(isMainOperation);