review comments

Author: W-A-James

src/cmap/wire_protocol/on_data.ts

@@ -1,7 +1,6 @@
 import { type EventEmitter } from 'events';
 
-import { MongoOperationTimeoutError } from '../../error';
-import { type TimeoutContext, TimeoutError } from '../../timeout';
+import { type TimeoutContext } from '../../timeout';
 import { List, promiseWithResolvers } from '../../utils';
 
 /**
@@ -24,12 +23,6 @@ export function onData(
   emitter: EventEmitter,
   { timeoutContext }: { timeoutContext?: TimeoutContext }
 ) {
-  // NOTE: Uncomment the block below to capture stack traces for debugging purposes
-  // const capture: { stack?: string; name?: string; message?: string } = Object.create(null);
-  // capture.name = 'MongoOperationTimeoutError';
-  // capture.message = 'Timed out during socket read';
-  // Error.captureStackTrace(capture);
-
   // Setup pending events and pending promise lists
   /**
    * When the caller has not yet called .next(), we store the
@@ -112,15 +105,9 @@ export function onData(
 
   function errorHandler(err: Error) {
     const promise = unconsumedPromises.shift();
-    const timeoutError = TimeoutError.is(err)
-      ? new MongoOperationTimeoutError('Timed out during socket read')
-      : undefined;
-
-    // NOTE: Uncomment this for debugging purposes
-    // if (timeoutError instanceof MongoOperationTimeoutError && capture) timeoutError.stack = capture.stack;
 
-    if (promise != null) promise.reject(timeoutError ?? err);
-    else error = timeoutError ?? err;
+    if (promise != null) promise.reject(err);
+    else error = err;
     void closeHandler();
   }
 

src/cursor/abstract_cursor.ts

@@ -201,11 +201,11 @@ export abstract class AbstractCursor<
         options.readPreference && options.readPreference instanceof ReadPreference
           ? options.readPreference
           : ReadPreference.primary,
-      ...pluckBSONSerializeOptions(options)
+      ...pluckBSONSerializeOptions(options),
+      timeoutMS: options.timeoutMS,
+      tailable: options.tailable,
+      awaitData: options.awaitData
     };
-    this.cursorOptions.timeoutMS = options.timeoutMS;
-    this.cursorOptions.tailable = options.tailable;
-    this.cursorOptions.awaitData = options.awaitData;
     if (this.cursorOptions.timeoutMS != null) {
       if (options.timeoutMode == null) {
         if (options.tailable) {
@@ -784,8 +784,7 @@ export abstract class AbstractCursor<
     const getMoreOptions = {
       ...this.cursorOptions,
       session: this.cursorSession,
-      batchSize,
-      omitMaxTimeMS: this.cursorOptions.omitMaxTimeMS
+      batchSize
     };
 
     if (
@@ -822,6 +821,8 @@ export abstract class AbstractCursor<
     }
     try {
       const state = await this._initialize(this.cursorSession);
+      // Set omitMaxTimeMS to the value needed for subsequent getMore calls
+      this.cursorOptions.omitMaxTimeMS = this.cursorOptions.timeoutMS != null;
       const response = state.response;
       this.selectedServer = state.server;
       this.cursorId = response.id;
@@ -865,7 +866,6 @@ export abstract class AbstractCursor<
 
     // otherwise need to call getMore
     const batchSize = this.cursorOptions.batchSize || 1000;
-    this.cursorOptions.omitMaxTimeMS = this.cursorOptions.timeoutMS != null;
     try {
       const response = await this.getMore(batchSize);
       this.cursorId = response.id;

test/integration/client-side-operations-timeout/node_csot.test.ts

@@ -26,6 +26,9 @@ import { type FailPoint } from '../../tools/utils';
 const metadata = { requires: { mongodb: '>=4.4' } };
 
 describe('CSOT driver tests', metadata, () => {
+  // NOTE: minPoolSize here is set to ensure that connections are available when testing timeout
+  // behaviour. This reduces flakiness in our tests since operations will not spend time
+  // establishing connections, more closely mirroring long-running application behaviour
   const minPoolSize = 20;
 
   describe('timeoutMS inheritance', () => {
@@ -651,6 +654,11 @@ describe('CSOT driver tests', metadata, () => {
             e => e
           );
           expect(maybeError).to.be.instanceOf(MongoOperationTimeoutError);
+
+          const finds = commandStarted.filter(x => x.commandName === 'find');
+          const getMores = commandStarted.filter(x => x.commandName === 'getMore');
+          expect(finds).to.have.lengthOf(1);
+          expect(getMores).to.have.lengthOf(0);
         });
 
         it('refreshes the timeout for subsequent getMores', async function () {
@@ -730,6 +738,11 @@ describe('CSOT driver tests', metadata, () => {
             e => e
           );
           expect(maybeError).to.be.instanceOf(MongoOperationTimeoutError);
+
+          const finds = commandStarted.filter(x => x.commandName === 'find');
+          const getMores = commandStarted.filter(x => x.commandName === 'getMore');
+          expect(finds).to.have.lengthOf(1);
+          expect(getMores).to.have.lengthOf(0);
         });
 
         it('refreshes the timeout for subsequent getMores', metadata, async function () {