NATS Server 2.15.2

Changelog

Refer to the 2.15 Upgrade Guide for backwards compatibility notes with 2.14.x.

Go Version

• 1.27.2 (#8740)

Dependencies

• github.com/klauspost/compress v1.20.1 (#8737)
• github.com/nats-io/nats.go v1.53.1 (#8737)

Changed

JetStream

• The max_ha_assets limit is now enforced consistently by the metalayer leader during stream and consumer placement, scaling and moves (#8639)

Gateways

• Support for sending and handling the legacy $GR. reply prefix, used by servers prior to v2.1.2, has been removed (#8615)

Improved

JetStream

• Stalled source and mirror flow control is now reported in stream info and warning logs, making missing $JS.FC.> imports or exports easier to diagnose (#8633)
• Stream and consumer placement now prefers peers that have caught up with the metalayer, reducing delays in API responses (#8643)
• Improved the performance of deleting entries from and encoding AVL sequence sets (#8646)
• Fast batch publish now reports backward sequence gaps as well as forward gaps (#8699)
• Stream pending message calculations avoid unnecessary filestore cache access and handle deleted sequence ranges more efficiently (#8680, #8681)
• Stream restore format detection now stops after the first S2 chunk (#8693)
• Stream restore waits for the preferred node to become leader, avoiding an incorrect create response during clustered restore (#8690) …

Changelog

Refer to the 2.15 Upgrade Guide for backwards compatibility notes with 2.14.x. This release also contains all changes up to and including v2.14.7.

Go Version

• 1.27.1 (#8551)

Added

JetStream

• Desired state metalayer (#8432, #8437, #8439, #8443, #8452, #8460, #8476, #8576, #8598, #8602, #8603)
• A new desired state reconciliation engine for streams and consumers considerably improves the safety and reliability of asset moves and scales
• Updating the placement or replication factor midway through an existing scale/move operation, cancelling an in-flight scale/move, or peer-removing is now much safer
• ADR：https://github.com/nats-io/nats-architecture-and-design/blob/main/adr/ADR-62.md
• Cancel stream move endpoint (#8476)
• An in-flight scale/move operation on a stream can be cancelled and the asset returned to its original placement using the new $JS.API.STREAM.CANCEL_MOVE endpoint
• ADR：https://github.com/nats-io/nats-architecture-and-design/blob/main/adr/ADR-62.md
• Evacuate endpoints (#8443)
• The new $JS.API.SERVER.EVACUATE endpoint can safely evacuate streams, and any consumers on those streams, from a node
• The new $JS.API.STREAM.PEER.EVACUATE.* endpoint can safely evacuate a peer, and any consumers on that peer, from a stream …

Changelog

Refer to the 2.14 Upgrade Guide for backwards compatibility notes with 2.12.x. Please note that the 2.13.x version was skipped.

Go Version

• 1.26.8 (#8551)

Dependencies

• github.com/antithesishq/antithesis-sdk-go v0.8.0-default-no-op (#8562)
• github.com/klauspost/compress v1.20.0 (#8562)
• golang.org/x/crypto v0.57.0 (#8597)
• golang.org/x/sys v0.48.0 (#8597)
• golang.org/x/time v0.16.0 (#8597)

Added

JetStream

• Compatibility for the new desired state metalayer, introduced in v2.15, to support safe upgrades and downgrades (#8554)

Improved

General

• The fastrand and math/rand packages have been replaced with math/rand/v2 (#8538, #8557)
• Reduced lock contention that could arise from tracking event IDs or closed connections (#8533)

JetStream

• When syncing deletes from a snapshot, block removals are now aggregated, reducing pending calculations (#8545)
• Message size checks are now performed before more expensive header checks (#8561)
• Pending calculations are now considerably faster when the max messages per subject limit is 1 (#8567)

Fixed

General

• The {{left}} and {{right}} mapping functions now work correctly in account mappings and source/mirror transforms (#8568)

JetStream

• A potential underflow when calculating deletes in skip messages has been fixed (#8546) …