refactor(NODE-6056): implement MongoDBResponse class

Author: nbbeeken

src/cmap/auth/gssapi.ts

@@ -29,11 +29,9 @@ type MechanismProperties = {
 async function externalCommand(
   connection: Connection,
   command: ReturnType<typeof saslStart> | ReturnType<typeof saslContinue>
-): Promise<{ payload: string; conversationId: any }> {
-  return await (connection.command(ns('$external.$cmd'), command, undefined) as Promise<{
-    payload: string;
-    conversationId: any;
-  }>);
+): Promise<{ payload: string; conversationId: number }> {
+  const response = await connection.command(ns('$external.$cmd'), command);
+  return response as { payload: string; conversationId: number };
 }
 
 let krb: typeof Kerberos;

src/cmap/commands.ts

@@ -53,9 +53,6 @@ export interface OpQueryOptions extends CommandOptions {
   exhaustAllowed?: boolean;
 }
 
-/**************************************************************
- * QUERY
- **************************************************************/
 /** @internal */
 export class OpQueryRequest {
   ns: string;
@@ -289,7 +286,7 @@ export interface OpResponseOptions extends BSONSerializeOptions {
 }
 
 /** @internal */
-export class OpQueryResponse {
+export class OpReply {
   parsed: boolean;
   raw: Buffer;
   data: Buffer;
@@ -303,7 +300,6 @@ export class OpQueryResponse {
   cursorId?: Long;
   startingFrom?: number;
   numberReturned?: number;
-  documents: (Document | Buffer)[] = new Array(0);
   cursorNotFound?: boolean;
   queryFailure?: boolean;
   shardConfigStale?: boolean;
@@ -313,7 +309,8 @@ export class OpQueryResponse {
   promoteValues: boolean;
   promoteBuffers: boolean;
   bsonRegExp?: boolean;
-  index?: number;
+  index = 0;
+  sections: Uint8Array[] = [];
 
   /** moreToCome is an OP_MSG only concept */
   moreToCome = false;
@@ -356,29 +353,9 @@ export class OpQueryResponse {
     return this.parsed;
   }
 
-  parse(options: OpResponseOptions): void {
+  parse(): Uint8Array {
     // Don't parse again if not needed
-    if (this.parsed) return;
-    options = options ?? {};
-
-    // Allow the return of raw documents instead of parsing
-    const raw = options.raw || false;
-    const documentsReturnedIn = options.documentsReturnedIn || null;
-    const useBigInt64 = options.useBigInt64 ?? this.opts.useBigInt64;
-    const promoteLongs = options.promoteLongs ?? this.opts.promoteLongs;
-    const promoteValues = options.promoteValues ?? this.opts.promoteValues;
-    const promoteBuffers = options.promoteBuffers ?? this.opts.promoteBuffers;
-    const bsonRegExp = options.bsonRegExp ?? this.opts.bsonRegExp;
-    let bsonSize;
-
-    // Set up the options
-    const _options: BSONSerializeOptions = {
-      useBigInt64,
-      promoteLongs,
-      promoteValues,
-      promoteBuffers,
-      bsonRegExp
-    };
+    if (this.parsed) return this.sections[0];
 
     // Position within OP_REPLY at which documents start
     // (See https://www.mongodb.com/docs/manual/reference/mongodb-wire-protocol/#wire-op-reply)
@@ -390,8 +367,11 @@ export class OpQueryResponse {
     this.startingFrom = this.data.readInt32LE(12);
     this.numberReturned = this.data.readInt32LE(16);
 
-    // Preallocate document array
-    this.documents = new Array(this.numberReturned);
+    if (this.numberReturned < 0 || this.numberReturned > 2 ** 32 - 1) {
+      throw new RangeError(
+        `OP_REPLY numberReturned is an invalid array length ${this.numberReturned}`
+      );
+    }
 
     this.cursorNotFound = (this.responseFlags & CURSOR_NOT_FOUND) !== 0;
     this.queryFailure = (this.responseFlags & QUERY_FAILURE) !== 0;
@@ -400,67 +380,26 @@ export class OpQueryResponse {
 
     // Parse Body
     for (let i = 0; i < this.numberReturned; i++) {
-      bsonSize =
+      const bsonSize =
         this.data[this.index] |
         (this.data[this.index + 1] << 8) |
         (this.data[this.index + 2] << 16) |
         (this.data[this.index + 3] << 24);
 
-      // If we have raw results specified slice the return document
-      if (raw) {
-        this.documents[i] = this.data.slice(this.index, this.index + bsonSize);
-      } else {
-        this.documents[i] = BSON.deserialize(
-          this.data.slice(this.index, this.index + bsonSize),
-          _options
-        );
-      }
+      const section = this.data.subarray(this.index, this.index + bsonSize);
+      this.sections.push(section);
 
       // Adjust the index
       this.index = this.index + bsonSize;
     }
 
-    if (this.documents.length === 1 && documentsReturnedIn != null && raw) {
-      const fieldsAsRaw: Document = {};
-      fieldsAsRaw[documentsReturnedIn] = true;
-      _options.fieldsAsRaw = fieldsAsRaw;
-
-      const doc = BSON.deserialize(this.documents[0] as Buffer, _options);
-      this.documents = [doc];
-    }
-
     // Set parsed
     this.parsed = true;
+
+    return this.sections[0];
   }
 }
 
-// Implementation of OP_MSG spec:
-// https://github.com/mongodb/specifications/blob/master/source/message/OP_MSG.rst
-//
-// struct Section {
-//   uint8 payloadType;
-//   union payload {
-//       document  document; // payloadType == 0
-//       struct sequence { // payloadType == 1
-//           int32      size;
-//           cstring    identifier;
-//           document*  documents;
-//       };
-//   };
-// };
-
-// struct OP_MSG {
-//   struct MsgHeader {
-//       int32  messageLength;
-//       int32  requestID;
-//       int32  responseTo;
-//       int32  opCode = 2013;
-//   };
-//   uint32      flagBits;
-//   Section+    sections;
-//   [uint32     checksum;]
-// };
-
 // Msg Flags
 const OPTS_CHECKSUM_PRESENT = 1;
 const OPTS_MORE_TO_COME = 2;
@@ -603,8 +542,8 @@ export class OpMsgResponse {
   promoteValues: boolean;
   promoteBuffers: boolean;
   bsonRegExp: boolean;
-  documents: (Document | Buffer)[];
-  index?: number;
+  index = 0;
+  sections: Uint8Array[] = [];
 
   constructor(
     message: Buffer,
@@ -642,47 +581,26 @@ export class OpMsgResponse {
     this.promoteBuffers =
       typeof this.opts.promoteBuffers === 'boolean' ? this.opts.promoteBuffers : false;
     this.bsonRegExp = typeof this.opts.bsonRegExp === 'boolean' ? this.opts.bsonRegExp : false;
-
-    this.documents = [];
   }
 
   isParsed(): boolean {
     return this.parsed;
   }
 
-  parse(options: OpResponseOptions): void {
+  parse(): Uint8Array {
     // Don't parse again if not needed
-    if (this.parsed) return;
-    options = options ?? {};
+    if (this.parsed) return this.sections[0];
 
     this.index = 4;
-    // Allow the return of raw documents instead of parsing
-    const raw = options.raw || false;
-    const documentsReturnedIn = options.documentsReturnedIn || null;
-    const useBigInt64 = options.useBigInt64 ?? this.opts.useBigInt64;
-    const promoteLongs = options.promoteLongs ?? this.opts.promoteLongs;
-    const promoteValues = options.promoteValues ?? this.opts.promoteValues;
-    const promoteBuffers = options.promoteBuffers ?? this.opts.promoteBuffers;
-    const bsonRegExp = options.bsonRegExp ?? this.opts.bsonRegExp;
-    const validation = this.parseBsonSerializationOptions(options);
-
-    // Set up the options
-    const bsonOptions: BSONSerializeOptions = {
-      useBigInt64,
-      promoteLongs,
-      promoteValues,
-      promoteBuffers,
-      bsonRegExp,
-      validation
-      // Due to the strictness of the BSON libraries validation option we need this cast
-    } as BSONSerializeOptions & { validation: { utf8: { writeErrors: boolean } } };
 
     while (this.index < this.data.length) {
       const payloadType = this.data.readUInt8(this.index++);
       if (payloadType === 0) {
         const bsonSize = this.data.readUInt32LE(this.index);
-        const bin = this.data.slice(this.index, this.index + bsonSize);
-        this.documents.push(raw ? bin : BSON.deserialize(bin, bsonOptions));
+        const bin = this.data.subarray(this.index, this.index + bsonSize);
+
+        this.sections.push(bin);
+
         this.index += bsonSize;
       } else if (payloadType === 1) {
         // It was decided that no driver makes use of payload type 1
@@ -692,25 +610,9 @@ export class OpMsgResponse {
       }
     }
 
-    if (this.documents.length === 1 && documentsReturnedIn != null && raw) {
-      const fieldsAsRaw: Document = {};
-      fieldsAsRaw[documentsReturnedIn] = true;
-      bsonOptions.fieldsAsRaw = fieldsAsRaw;
-      const doc = BSON.deserialize(this.documents[0] as Buffer, bsonOptions);
-      this.documents = [doc];
-    }
-
     this.parsed = true;
-  }
-
-  parseBsonSerializationOptions({ enableUtf8Validation }: BSONSerializeOptions): {
-    utf8: { writeErrors: false } | false;
-  } {
-    if (enableUtf8Validation === false) {
-      return { utf8: false };
-    }
 
-    return { utf8: { writeErrors: false } };
+    return this.sections[0];
   }
 }