fix _id generation in bulk writes && misc cleanups

src/bulk/common.ts

@@ -1,6 +1,6 @@
 import { promisify } from 'util';
 
-import { type BSONSerializeOptions, type Document, ObjectId, resolveBSONOptions } from '../bson';
+import { type BSONSerializeOptions, type Document, resolveBSONOptions } from '../bson';
 import type { Collection } from '../collection';
 import {
   type AnyError,
@@ -12,6 +12,7 @@ import {
 } from '../error';
 import type { Filter, OneOrMore, OptionalId, UpdateFilter, WithoutId } from '../mongo_types';
 import type { CollationOptions, CommandOperationOptions } from '../operations/command';
+import { maybeAddIdToDocuments } from '../operations/common_functions';
 import { DeleteOperation, type DeleteStatement, makeDeleteStatement } from '../operations/delete';
 import { executeOperation } from '../operations/execute_operation';
 import { InsertOperation } from '../operations/insert';
@@ -917,7 +918,7 @@ export abstract class BulkOperationBase {
    * Create a new OrderedBulkOperation or UnorderedBulkOperation instance
    * @internal
    */
-  constructor(collection: Collection, options: BulkWriteOptions, isOrdered: boolean) {
+  constructor(private collection: Collection, options: BulkWriteOptions, isOrdered: boolean) {
     // determine whether bulkOperation is ordered or unordered
     this.isOrdered = isOrdered;
 
@@ -1032,9 +1033,9 @@ export abstract class BulkOperationBase {
    * ```
    */
   insert(document: Document): BulkOperationBase {
-    if (document._id == null && !shouldForceServerObjectId(this)) {
-      document._id = new ObjectId();
-    }
+    maybeAddIdToDocuments(this.collection, document, {
+      forceServerObjectId: this.shouldForceServerObjectId()
+    });
 
     return this.addToOperationsList(BatchType.INSERT, document);
   }
@@ -1093,21 +1094,16 @@ export abstract class BulkOperationBase {
       throw new MongoInvalidArgumentError('Operation must be an object with an operation key');
     }
     if ('insertOne' in op) {
-      const forceServerObjectId = shouldForceServerObjectId(this);
-      if (op.insertOne && op.insertOne.document == null) {
-        // NOTE: provided for legacy support, but this is a malformed operation
-        if (forceServerObjectId !== true && (op.insertOne as Document)._id == null) {
-          (op.insertOne as Document)._id = new ObjectId();
-        }
-
-        return this.addToOperationsList(BatchType.INSERT, op.insertOne);
-      }
+      const forceServerObjectId = this.shouldForceServerObjectId();
+      const document =
+        op.insertOne && op.insertOne.document == null
+          ? // NOTE: provided for legacy support, but this is a malformed operation
+            (op.insertOne as Document)
+          : op.insertOne.document;
 
-      if (forceServerObjectId !== true && op.insertOne.document._id == null) {
-        op.insertOne.document._id = new ObjectId();
-      }
+      maybeAddIdToDocuments(this.collection, document, { forceServerObjectId });
 
-      return this.addToOperationsList(BatchType.INSERT, op.insertOne.document);
+      return this.addToOperationsList(BatchType.INSERT, document);
     }
 
     if ('replaceOne' in op || 'updateOne' in op || 'updateMany' in op) {
@@ -1268,6 +1264,18 @@ export abstract class BulkOperationBase {
     batchType: BatchType,
     document: Document | UpdateStatement | DeleteStatement
   ): this;
+
+  private shouldForceServerObjectId(): boolean {
+    if (typeof this.s.options.forceServerObjectId === 'boolean') {
+      return this.s.options.forceServerObjectId;
+    }
+
+    if (typeof this.s.collection.s.db.options?.forceServerObjectId === 'boolean') {
+      return this.s.collection.s.db.options?.forceServerObjectId;
+    }
+
+    return false;
+  }
 }
 
 Object.defineProperty(BulkOperationBase.prototype, 'length', {
@@ -1277,18 +1285,6 @@ Object.defineProperty(BulkOperationBase.prototype, 'length', {
   }
 });
 
-function shouldForceServerObjectId(bulkOperation: BulkOperationBase): boolean {
-  if (typeof bulkOperation.s.options.forceServerObjectId === 'boolean') {
-    return bulkOperation.s.options.forceServerObjectId;
-  }
-
-  if (typeof bulkOperation.s.collection.s.db.options?.forceServerObjectId === 'boolean') {
-    return bulkOperation.s.collection.s.db.options?.forceServerObjectId;
-  }
-
-  return false;
-}
-
 function isInsertBatch(batch: Batch): boolean {
   return batch.batchType === BatchType.INSERT;
 }

src/operations/common_functions.ts

@@ -43,26 +43,37 @@ export async function indexInformation(
   return info;
 }
 
-export function prepareDocs(
+export function maybeAddIdToDocuments(
   coll: Collection,
   docs: Document[],
   options: { forceServerObjectId?: boolean }
-): Document[] {
+): Document[];
+export function maybeAddIdToDocuments(
+  coll: Collection,
+  docs: Document,
+  options: { forceServerObjectId?: boolean }
+): Document;
+export function maybeAddIdToDocuments(
+  coll: Collection,
+  docOrDocs: Document[] | Document,
+  options: { forceServerObjectId?: boolean }
+): Document[] | Document {
   const forceServerObjectId =
     typeof options.forceServerObjectId === 'boolean'
       ? options.forceServerObjectId
       : coll.s.db.options?.forceServerObjectId;
 
   // no need to modify the docs if server sets the ObjectId
   if (forceServerObjectId === true) {
-    return docs;
+    return docOrDocs;
   }
 
-  return docs.map(doc => {
+  const transform = (doc: Document): Document => {
     if (doc._id == null) {
       doc._id = coll.s.pkFactory.createPk();
     }
 
     return doc;
-  });
+  };
+  return Array.isArray(docOrDocs) ? docOrDocs.map(transform) : transform(docOrDocs);
 }

src/operations/insert.ts

@@ -9,7 +9,7 @@ import type { MongoDBNamespace } from '../utils';
 import { WriteConcern } from '../write_concern';
 import { BulkWriteOperation } from './bulk_write';
 import { CommandOperation, type CommandOperationOptions } from './command';
-import { prepareDocs } from './common_functions';
+import { maybeAddIdToDocuments } from './common_functions';
 import { AbstractOperation, Aspect, defineAspects } from './operation';
 
 /** @internal */
@@ -69,7 +69,7 @@ export interface InsertOneResult<TSchema = Document> {
 
 export class InsertOneOperation extends InsertOperation {
   constructor(collection: Collection, doc: Document, options: InsertOneOptions) {
-    super(collection.s.namespace, prepareDocs(collection, [doc], options), options);
+    super(collection.s.namespace, maybeAddIdToDocuments(collection, [doc], options), options);
   }
 
   override async execute(
@@ -131,7 +131,9 @@ export class InsertManyOperation extends AbstractOperation<InsertManyResult> {
     const writeConcern = WriteConcern.fromOptions(options);
     const bulkWriteOperation = new BulkWriteOperation(
       coll,
-      prepareDocs(coll, this.docs, options).map(document => ({ insertOne: { document } })),
+      maybeAddIdToDocuments(coll, this.docs, options).map(document => ({
+        insertOne: { document }
+      })),
       options
     );