mongodb/mongo-cxx-driver r4.3.0

MongoDB C++11 Driver r4.3.0

on GitHub

Fixed

• Added missing subscript operators for class types declared in bsoncxx::vector::iterators.

Deprecated

• Support for Visual Studio 2015 (EOL since Oct 2025). Use Visual Studio 2017 or newer.

Changed

• Bump the minimum required C Driver version to 2.3.0.

Added

• Added support for MongoDB's Intelligent Workload Management (IWM) and ingress connection rate limiting features. The driver now gracefully handles write-blocking scenarios and optimizes connection establishment during high-load conditions to maintain application availability.
  • Supported on all commands.
  • Custom application retry logic may need to be adjusted to avoid retrying too long.
  • Upgrade is recommended to avoid impacts of server changes related to overload errors.
    • If not upgrading, custom application retry logic may need to be adjusted to handle higher rates of overload errors.
  • Add URI option maxAdaptiveRetries to configure the maximum number of retries for operations that fail with a SystemOverloadedError (default: 2).
  • Add URI option enableOverloadRetargeting to control whether retries of SystemOverloadedError will attempt to use a different server (default: false).

See the full list of changes in Jira.

Feedback

To report a bug or request a feature, please open a ticket in the MongoDB issue management tool Jira:

• Create an account and login.
• Navigate to the CXX project
• Click Create.

Signature Verification

Release artifacts may be verified by using the accompanying detached signature (.asc) and the cpp-driver public key obtained from https://pgp.mongodb.com.