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npm · #3169 most downloaded on npm
The official MongoDB driver for Node.js
Last release today
04 Oct 2026
Ships on a steady schedule
a new release about every 8 days
Nearly every release is documented
notes for 60 of the last 60 stable releases
195 versions withdrawn
withdrawn after publishing
15 years old
922 releases · first in 2011
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The MongoDB Node.js team is pleased to announce version 6.6.2 of the mongodb package!
The MongoDB Node.js team is pleased to announce version 6.6.2 of the mongodb package!
Starting in version 6.6.0, when using the stream server monitoring mode, heartbeats were incorrectly timed as having a duration of 0, leading to server selection viewing each server as equally desirable for selection.
We invite you to try the mongodb library immediately, and report any issues to the NODE project.
One column per quarter.
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The MongoDB Node.js team is pleased to announce version 6.6.1 of the mongodb package!
The MongoDB Node.js team is pleased to announce version 6.6.1 of the mongodb package!
ref()-ed timer keeps event loop running until client.connect() resolvesWhen the MongoClient is first starting up (client.connect()) monitoring connections begin the process of discovering servers to make them selectable. The ref()-ed serverSelectionTimeoutMS timer keeps Node.js' event loop running as the monitoring connections are created. In the last release we inadvertently unref()-ed this initial timer which would allow Node.js to close before the monitors could create connections.
We invite you to try the mongodb library immediately, and report any issues to the NODE project.
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The MongoDB Node.js team is pleased to announce version 6.6.0 of the mongodb package!
The MongoDB Node.js team is pleased to announce version 6.6.0 of the mongodb package!
When creating an aggregation pipeline cursor, a new generic method addStage() has been added in the fluid API for users to add aggregation pipeline stages in a general manner.
const documents = await users.aggregate().addStage({ $project: { name: true } }).toArray();
Thank you @prenaissance for contributing this feature!
MongoMissingDependencyErrorsMongoMissingDependencyErrors now include a cause and a dependencyName field, which can be used to programmatically determine which package is missing and why the driver failed to load it.
For example:
MongoMissingDependencyError: The iHateJavascript module does not exist
at findOne (mongodb/main.js:7:11)
at Object.<anonymous> (mongodb/main.js:14:1)
... 3 lines matching cause stack trace ...
at Module._load (node:internal/modules/cjs/loader:1021:12) {
dependencyName: 'iHateJavascript',
[Symbol(errorLabels)]: Set(0) {},
[cause]: Error: Cannot find module 'iHateJavascript'
Require stack:
- mongodb/main.js
at require (node:internal/modules/helpers:179:18)
at findOne (mongodb/main.js:5:5)
at Object.<anonymous> (mongodb/main.js:14:1) {
code: 'MODULE_NOT_FOUND',
requireStack: [ 'mongodb/main.js' ]
}
}
ServerDescription Round Trip Time (RTT) measurement changesServerDescription.roundTripTime is now a moving averagePreviously, ServerDescription.roundTripTime was calculated as a weighted average of the most recently observed heartbeat duration and the previous duration. This update changes this behaviour to average ServerDescription.roundTripTime over the last 10 observed heartbeats. This should reduce the likelihood that the selected server changes as a result of momentary spikes in server latency.
minRoundTripTime to ServerDescriptionA new minRoundTripTime property is now available on the ServerDescription class which gives the minimum RTT over the last 10 heartbeats. Note that this value will be reported as 0 when fewer than 2 samples have been observed.
type supported in SearchIndexDescriptionIt is now possible to specify the type of a search index when creating a search index:
const indexName = await collection.createSearchIndex({
name: 'my-vector-search-index',
// new! specifies that a `vectorSearch` index is created
type: 'vectorSearch',
definition: {
mappings: { dynamic: false }
}
});
Collection.findOneAndModify's UpdateFilter.$currentDate no longer throws on collections with limited schemaExample:
// collection has no schema
collection.update(
$currentData: {
lastModified: true
} // no longer throws a TS error
);
TopologyDescription now properly stringifies itself to JSONThe TopologyDescription class is exposed by the driver in server selection errors and topology monitoring events to provide insight into the driver's current representation of the server's topology and to aid in debugging. However, the TopologyDescription uses Maps internally, which get serialized to {} when JSON stringified. We recommend using Node's util.inspect() helper to print topology descriptions because inspect properly handles all JS types and all types we use in the driver. However, if JSON must be used, the TopologyDescription now provides a custom toJSON() hook:
client.on('topologyDescriptionChanged', ({ newDescription }) => {
// recommended!
console.log('topology description changed', inspect(newDescription, { depth: Infinity, colors: true }))
// now properly prints the entire topology description
console.log('topology description changed', JSON.stringify(newDescription))
});
readConcern and writeConcern in Collection.listSearchIndexes options argument[!Important]
readConcernandwriteConcernare no longer viable keys in the options argument passed intoCollection.listSearchIndexes
This type change is a correctness fix.
Collection.listSearchIndexes is an Atlas specific method, and Atlas' search indexes do not support readConcern and writeConcern options. The types for this function now reflect this functionality.
ReadPreferenceMode other than 'primary'The following error will now only be thrown when a user provides a ReadPreferenceMode other than primary and then tries to perform a command that involves a read:
new MongoTransactionError('Read preference in a transaction must be primary');
Prior to this change, the Node Driver would incorrectly throw this error even when the operation does not perform a read.
Note: a RunCommandOperation is treated as a read operation for this error.
TopologyDescription.error type is MongoError[!Important]
TheTopologyDescription.errorproperty type is nowMongoErrorrather thanMongoServerError.
This type change is a correctness fix.
Before this change, the following errors that were not instances of MongoServerError were already passed into TopologyDescription.error at runtime:
MongoNetworkError (excluding MongoNetworkRuntimeError)MongoError with a MongoErrorLabel.HandshakeError labelindexExists() no longer supports the full optionThe Collection.indexExists() helper supported an option, full, that modified the internals of the method. When full was set to true, the driver would always return false, regardless of whether or not the index exists.
The full option is intended to modify the return type of index enumeration APIs (Collection.indexes() and Collection.indexInformation(), but since the return type of Collection.indexExists() this option does not make sense for the Collection.indexExists() helper.
We have removed support for this option.
indexExists(), indexes() and indexInformation() support cursor options in TypescriptThese APIs have supported cursor options at runtime since the 4.x version of the driver, but our Typescript has incorrectly omitted cursor options from these APIs.
Collection.indexInformation(), Collection.indexes() and Db.indexInformation() are helpers that return index information for a given collection or database. These helpers take an option, full, that configures whether the return value contains full index descriptions or a compact summary:
collection.indexes({ full: true }); // returns an array of index descriptions
collection.indexes({ full: false }); // returns an object, mapping index names to index keys
However, the Typescript return type of these helpers was always Document. Thanks to @prenaissance, these helpers now have accurate type information! The helpers return a new type, IndexDescriptionCompact | IndexDescriptionInfo[], which accurately reflects the return type of these helpers. The helpers also support type narrowing by providing a boolean literal as an option to the API:
collection.indexes(); // returns `IndexDescriptionCompact | IndexDescriptionInfo[]`
collection.indexes({ full: false }); // returns an `IndexDescriptionCompact`
collection.indexes({ full: true }); // returns an `IndexDescriptionInfo[]`
collection.indexInfo(); // returns `IndexDescriptionCompact | IndexDescriptionInfo[]`
collection.indexInfo({ full: false }); // returns an `IndexDescriptionCompact`
collection.indexInfo({ full: true }); // returns an `IndexDescriptionInfo[]`
db.indexInfo(); // returns `IndexDescriptionCompact | IndexDescriptionInfo[]`
db.indexInfo({ full: false }); // returns an `IndexDescriptionCompact`
db.indexInfo({ full: true }); // returns an `IndexDescriptionInfo[]`
In addition to letting users provide KMS credentials manually, client-side encryption supports fetching AWS KMS credentials on-demand using the AWS SDK. However, AWS credential mechanisms that returned access keys with expiration timestamps caused the driver to throw an error.
The driver will no longer throw an error when receiving an expiration token from the AWS SDK.
ClusterTime interface signature optionalityThe ClusterTime interface incorrectly reported the signature field as required, the server may omit it, so the typescript has been updated to reflect reality.
timeoutMS and defaultTimeoutMS (#4068) (ddd1e81)cause and package name for all MongoMissingDependencyErrors (#4067) (62ea94b)minRoundTripTime to ServerDescription and change roundTripTime to a moving average (#4059) (0e3d6ea)type option in create search index helpers (#4060) (3598c23)bson to ^6.5.0 (#4035) (8ab2055)bson to ^6.7.0 (#4099) (7f191cf)Collection.findOneAndModify UpdateFilter.$currentDate (#4047) (a8670a7)ReadPreferenceMode other than primary (#4075) (39fc198)v to createIndexes command when version is specified (#4043) (1879a04)TopologyDescription.error type to MongoError (#4028) (30432e8)full is set to true (#4034) (0ebc1ac)libmongocrypt after fetching AWS KMS credentials (#4057) (c604e74)ClusterTime.signature can be undefined (#4069) (ce55ca9)We invite you to try the mongodb library immediately, and report any issues to the NODE project.
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…it outside of a major version, but we have deprecated it and will be removing it in the next major version.
The MongoDB Node.js team is pleased to announce version 6.5.0 of the mongodb package!
pkFactoryWhen performing inserts, the driver automatically generates _ids for each document if there is no _id present. By default, the driver generates ObjectIds. An option, pkFactory, can be used to configure the driver to generate _ids that are not object ids.
For a long time, only Collection.insert and Collection.insertMany actually used the pkFactory, if configured. Notably, Collection.bulkWrite(), Collection.initializeOrderedBulkOp() and Collection.initializeOrderedBulkOp() always generated ObjectIds, regardless of what was configured on collection.
The driver always generates _ids for inserted documents using the pkFactory.
[!CAUTION] If you are using a
pkFactoryand performing bulk writes, you may have inserted data into your database that does not have_ids generated by thepkFactory.
When connecting to a secondary in a replica set with a direct connection, if a read operation is performed, the driver attaches a read preference of primaryPreferred to the command.
The Connection class has recently been refactored to operate on our socket operations using promises. An oversight how we made async network operations interruptible made new promises for every operation. We've simplified the approach and corrected the leak.
When connecting using a convenient SRV connection string (mongodb+srv://) hostnames are obtained from an SRV dns lookup and some configuration options are obtained from a TXT dns query. Those DNS operations are now performed in parallel to reduce first-time connection latency.
The Node.js driver now keeps track of container metadata in the client.env.container field of the handshake document.
If space allows, the following metadata will be included in client.env.container:
env?: {
container?: {
orchestrator?: 'kubernetes' // if process.env.KUBERNETES_SERVICE_HOST is set
runtime?: 'docker' // if the '/.dockerenv' file exists
}
}
Note: If neither Kubernetes nor Docker is present, client.env will not have the container property.
errorResponse to MongoServerErrorThe MongoServer error maps keys from the error document returned by the server on to itself. There are some use cases where the original error document is desirable to obtain in isolation. So now, the mongoServerError.errorResponse property stores a reference to the error document returned by the server.
CloseOptions interfaceThe CloseOptions interface was unintentionally made public and was only intended for use in the driver's internals. Due to recent refactoring (NODE-5915), this interface is no longer used in the driver. Since it was marked public, out of an abundance of caution we will not be removing it outside of a major version, but we have deprecated it and will be removing it in the next major version.
CERT_HAS_EXPIRED (#4014) (057c223)Connection class (#4022) (69de253)We invite you to try the mongodb library immediately, and report any issues to the NODE project.
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The MongoDB Node.js team is pleased to announce version 6.4.0 of the mongodb package!
The MongoDB Node.js team is pleased to announce version 6.4.0 of the mongodb package!
When retrying reads or writes on a sharded cluster, the driver will attempt to select a different mongos for the retry if multiple are present. This should heuristically avoid encountering the original error that caused the need to retry the operation.
Instead of creating a new AWS provider for each authentication, we cache the AWS credentials provider per client to prevent overwhelming the auth endpoint and ensure that cached credentials are not shared with other clients.
^6.4.0BSON has had a number of performance increases in the last two releases (6.3.0 and 6.4.0). Small basic latin (ASCII) only strings, small memory allocations (ObjectId and Decimal128) and numeric parsing operations (int32, doubles, and longs) have all had optimizations applied to them.
For details check out the release notes here: BSON 6.3.0 and BSON 6.4.0 :racehorse:
Read operations will be retried after receiving an error with the ExceededTimeLimit label.
Internal to the field-level encryption machinery is a helper that opens a TLS socket to the KMS provider endpoint and submits a KMS request. The code neglected to add a 'close' event listener to the socket, which had the potential to improperly leave the promise pending indefinitely if no error was encountered.
The authentication was rejected by the saslContinue command from mongosh due to missing "=" padding from the client. We fixed the way we parse payload to preserve trailing "="s.
countDocuments now types the filter using the collection SchemaPreviously, countDocuments had a weakly typed Document type for the filter allowing any JS object as input. The filter is now typed as Filter<Schema> to enable autocompletion, and, hopefully, catch minor bugs.
Thank you to @pashok88895 for contributing to this improvement.
$addToSet in bulkWrite was fixedPreviously the following code sample would show a type error:
interface IndexSingatureTestDocument extends Document {
readonly myId: number;
readonly mySet: number[];
}
const indexSingatureCollection = undefined as unknown as Collection<IndexSingatureTestDocument>;
indexSingatureCollection.bulkWrite([
{
updateOne: {
filter: { myId: 0 },
update: {
$addToSet: { mySet: 0 } // The type error! Type 'number' is not assignable to type 'never'.
}
}
}
]);
It happened because the driver's Document type falls back to any, and internally we could not distinguish whether or not this assignment was intentional and should be allowed.
After this change, users can extend their types from Document/any, or use properties of any type and we skip the $addToSet validation in those cases.
The ServerHeartbeatSucceeded and ServerHeartbeatFailed event have a duration property that represents the time it took to perform the hello handshake with MongoDB. The Monitor responsible for issuing heartbeats mistakenly included the time it took to create the socket in this field, which inflates the value with the time it takes to perform a DNS lookup, TCP, and TLS handshakes.
These were previously swallowed and now will be emitted on the error event:
const transform = new Transform({
transform(data, encoding, callback) {
callback(null, data);
},
});
const stream = db.collection('tests').find().sort({ studentId: -1 }).stream({ transform });
stream.on('error', err => {
// The error will properly be emitted here.
});
Users may provide an AWS_SESSION_TOKEN as a client option or AWS configuration in addition to a username and password. But if the token is not provided, the driver won't throw an exception and let AWS SDK handle the request.
^6.4.0 (#4007) (90f2f70)
We invite you to try the mongodb library immediately, and report any issues to the NODE project.
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The GridFS contentType and aliases options are deprecated. According to the GridFS spec, applications wishing to store contentType and aliases should…
The MongoDB Node.js team is pleased to announce version 6.3.0 of the mongodb package!
serverMonitoringModeFor users that want to control the behaviour of the monitoring connection between each node in the topology, a new option, serverMonitoringMode, has been added. This defaults to auto but can be forced into a specific mode by providing a value of poll or stream. When the setting is auto the monitoring mode will be determined by the environment the driver is running in, specifically, FaaS environments prefer "polling" mode and all others prefer "streaming".
A polling monitor periodically issues a hello command to the node at an interval of heartbeatFrequencyMS. A streaming monitor sends an initial hello and then will automatically get a response from the Node when a change in server configuration occurs or at a maximum time of heartbeatFrequencyMS. The value of that option defaults to 10000 milliseconds.
This new option can be provided in the connection string or as an option to the MongoClient.
// In the connection string.
new MongoClient('mongodb://127.0.0.1:27017/?serverMonitoringMode=stream');
// In the options
new MongoClient('mongodb://127.0.0.1:27017/', { serverMonitoringMode: 'stream' });
serverApi is enabledWhen enabling serverApi the driver's RTT measurement logic (used to determine the closest node) still sent the legacy hello command "isMaster" causing the server to return an error. Unfortunately, the error handling logic did not correctly destroy the socket which would cause a leak.
Both sending the correct hello command and the error handling connection clean-up logic are fixed in this change.
The GridFS contentType and aliases options are deprecated. According to the GridFS spec, applications wishing to store contentType and aliases should add a corresponding field to the metadata document instead.
The mongodb-connection-string-url package which parses connection strings relied on Node's punycode module, the package now imports the community package removing the deprecation warning on Node.js 20+.
We invite you to try the mongodb library immediately and report any issues to the NODE project.
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