fix(NODE-6362): cache cursor deserialization options across deserialize calls

src/bson.ts

@@ -132,3 +132,14 @@ export function resolveBSONOptions(
  options?.enableUtf8Validation ?? parentOptions?.enableUtf8Validation ?? true
  };
 }
+
+/** @internal */
+export function parseUtf8ValidationOption(options?: { enableUtf8Validation?: boolean }): {
+ utf8: { writeErrors: false } | false;
+} {
+ const enableUtf8Validation = options?.enableUtf8Validation;
+ if (enableUtf8Validation === false) {
+ return { utf8: false };
+ }
+ return { utf8: { writeErrors: false } };
+}

src/cmap/connection.ts

@@ -1,3 +1,4 @@
+import { type DeserializeOptions } from 'bson';
 import { type Readable, Transform, type TransformCallback } from 'stream';
 import { clearTimeout, setTimeout } from 'timers';
 
@@ -487,7 +488,7 @@ export class Connection extends TypedEventEmitter<ConnectionEvents> {
 
  // If `documentsReturnedIn` not set or raw is not enabled, use input bson options
  // Otherwise, support raw flag. Raw only works for cursors that hardcode firstBatch/nextBatch fields
- const bsonOptions =
+ const bsonOptions: DeserializeOptions =
  options.documentsReturnedIn == null || !options.raw
  ? options
  : {

src/cmap/wire_protocol/on_demand/document.ts

@@ -1,16 +1,16 @@
+import { type DeserializeOptions } from 'bson';
+
 import {
  Binary,
  type BSONElement,
  BSONError,
- type BSONSerializeOptions,
  BSONType,
  deserialize,
  getBigInt64LE,
  getFloat64LE,
  getInt32LE,
  ObjectId,
  parseToElementsToArray,
- pluckBSONSerializeOptions,
  Timestamp,
  toUTF8
 } from '../../../bson';
@@ -44,6 +44,14 @@ export type JSTypeOf = {
 /** @internal */
 type CachedBSONElement = { element: BSONElement; value: any | undefined };
 
+/**
+ * @internal
+ *
+ * Options for `OnDemandDocument.toObject()`. Validation is required to ensure
+ * that callers provide utf8 validation options. */
+export type OnDemandDocumentDeserializeOptions = Omit<DeserializeOptions, 'validation'> &
+ Required<Pick<DeserializeOptions, 'validation'>>;
+
 /** @internal */
 export class OnDemandDocument {
  /**
@@ -330,24 +338,12 @@ export class OnDemandDocument {
  * Deserialize this object, DOES NOT cache result so avoid multiple invocations
  * @param options - BSON deserialization options
  */
- public toObject(options?: BSONSerializeOptions): Record<string, any> {
- const exactBSONOptions = {
- ...pluckBSONSerializeOptions(options ?? {}),
- validation: this.parseBsonSerializationOptions(options),
+ public toObject(options?: OnDemandDocumentDeserializeOptions): Record<string, any> {
+ return deserialize(this.bson, {
+ ...options,
  index: this.offset,
  allowObjectSmallerThanBufferSize: true
- };
- return deserialize(this.bson, exactBSONOptions);
- }
-
- private parseBsonSerializationOptions(options?: { enableUtf8Validation?: boolean }): {
- utf8: { writeErrors: false } | false;
- } {
- const enableUtf8Validation = options?.enableUtf8Validation;
- if (enableUtf8Validation === false) {
- return { utf8: false };
- }
- return { utf8: { writeErrors: false } };
+ });
  }
 
  /** Returns this document's bytes only */

src/cmap/wire_protocol/responses.ts

@@ -1,16 +1,24 @@
+import { type DeserializeOptions } from 'bson';
+
 import {
  type BSONElement,
  type BSONSerializeOptions,
  BSONType,
  type Document,
  Long,
  parseToElementsToArray,
+ parseUtf8ValidationOption,
+ pluckBSONSerializeOptions,
  type Timestamp
 } from '../../bson';
 import { MongoUnexpectedServerResponseError } from '../../error';
 import { type ClusterTime } from '../../sdam/common';
 import { decorateDecryptionResult, ns } from '../../utils';
-import { type JSTypeOf, OnDemandDocument } from './on_demand/document';
+import {
+ type JSTypeOf,
+ OnDemandDocument,
+ type OnDemandDocumentDeserializeOptions
+} from './on_demand/document';
 
 // eslint-disable-next-line no-restricted-syntax
 const enum BSONElementOffset {
@@ -112,7 +120,8 @@ export class MongoDBResponse extends OnDemandDocument {
  this.get('recoveryToken', BSONType.object)?.toObject({
  promoteValues: false,
  promoteLongs: false,
- promoteBuffers: false
+ promoteBuffers: false,
+ validation: { utf8: true }
  }) ?? null
  );
  }
@@ -165,6 +174,14 @@ export class MongoDBResponse extends OnDemandDocument {
  }
  return this.clusterTime ?? null;
  }
+
+ public override toObject(options?: BSONSerializeOptions): Record<string, any> {
+ const exactBSONOptions = {
+ ...pluckBSONSerializeOptions(options ?? {}),
+ validation: parseUtf8ValidationOption(options)
+ };
+ return super.toObject(exactBSONOptions);
+ }
 }
 
 /** @internal */
@@ -248,12 +265,13 @@ export class CursorResponse extends MongoDBResponse {
  this.cursor.get('postBatchResumeToken', BSONType.object)?.toObject({
  promoteValues: false,
  promoteLongs: false,
- promoteBuffers: false
+ promoteBuffers: false,
+ validation: { utf8: true }
  }) ?? null
  );
  }
 
- public shift(options?: BSONSerializeOptions): any {
+ public shift(options: OnDemandDocumentDeserializeOptions): any {
  if (this.iterated >= this.batchSize) {
  return null;
  }
@@ -305,7 +323,7 @@ export class ExplainedCursorResponse extends CursorResponse {
  return this._length;
  }
 
- override shift(options?: BSONSerializeOptions | undefined) {
+ override shift(options?: DeserializeOptions) {
  if (this._length === 0) return null;
  this._length -= 1;
  return this.toObject(options);

src/cursor/abstract_cursor.ts

@@ -1,6 +1,7 @@
 import { Readable, Transform } from 'stream';
 
 import { type BSONSerializeOptions, type Document, Long, pluckBSONSerializeOptions } from '../bson';
+import { type OnDemandDocumentDeserializeOptions } from '../cmap/wire_protocol/on_demand/document';
 import { type CursorResponse } from '../cmap/wire_protocol/responses';
 import {
  MongoAPIError,
@@ -157,6 +158,9 @@ export abstract class AbstractCursor<
  /** @event */
  static readonly CLOSE = 'close' as const;
 
+ /** @internal */
+ protected deserializationOptions: OnDemandDocumentDeserializeOptions;
+
  /** @internal */
  protected constructor(
  client: MongoClient,
@@ -211,6 +215,13 @@ export abstract class AbstractCursor<
  } else {
  this.cursorSession = this.cursorClient.startSession({ owner: this, explicit: false });
  }
+
+ this.deserializationOptions = {
+ ...this.cursorOptions,
+ validation: {
+ utf8: options?.enableUtf8Validation === false ? false : true
+ }
+ };
  }
 
  /**
@@ -304,7 +315,7 @@ export abstract class AbstractCursor<
  );
 
  for (let count = 0; count < documentsToRead; count++) {
- const document = this.documents?.shift(this.cursorOptions);
+ const document = this.documents?.shift(this.deserializationOptions);
  if (document != null) {
  bufferedDocs.push(document);
  }
@@ -406,7 +417,7 @@ export abstract class AbstractCursor<
  }
 
  do {
- const doc = this.documents?.shift(this.cursorOptions);
+ const doc = this.documents?.shift(this.deserializationOptions);
  if (doc != null) {
  if (this.transform != null) return await this.transformDocument(doc);
  return doc;
@@ -425,15 +436,15 @@ export abstract class AbstractCursor<
  throw new MongoCursorExhaustedError();
  }
 
- let doc = this.documents?.shift(this.cursorOptions);
+ let doc = this.documents?.shift(this.deserializationOptions);
  if (doc != null) {
  if (this.transform != null) return await this.transformDocument(doc);
  return doc;
  }
 
  await this.fetchBatch();
 
- doc = this.documents?.shift(this.cursorOptions);
+ doc = this.documents?.shift(this.deserializationOptions);
  if (doc != null) {
  if (this.transform != null) return await this.transformDocument(doc);
  return doc;

src/cursor/aggregation_cursor.ts

@@ -76,7 +76,7 @@ export class AggregationCursor<TSchema = any> extends AbstractCursor<TSchema> {
  explain: verbosity ?? true
  })
  )
- ).shift(this.aggregateOptions);
+ ).shift(this.deserializationOptions);
  }
 
  /** Add a stage to the aggregation pipeline

src/cursor/find_cursor.ts

@@ -143,7 +143,7 @@ export class FindCursor<TSchema = any> extends AbstractCursor<TSchema> {
  explain: verbosity ?? true
  })
  )
- ).shift(this.findOptions);
+ ).shift(this.deserializationOptions);
  }
 
  /** Set the cursor query */

src/index.ts

@@ -302,7 +302,11 @@ export type { ClientMetadata, ClientMetadataOptions } from './cmap/handshake/cli
 export type { ConnectionPoolMetrics } from './cmap/metrics';
 export type { StreamDescription, StreamDescriptionOptions } from './cmap/stream_description';
 export type { CompressorName } from './cmap/wire_protocol/compression';
-export type { JSTypeOf, OnDemandDocument } from './cmap/wire_protocol/on_demand/document';
+export type {
+ JSTypeOf,
+ OnDemandDocument,
+ OnDemandDocumentDeserializeOptions
+} from './cmap/wire_protocol/on_demand/document';
 export type {
  CursorResponse,
  MongoDBResponse,