Module kraft 

Hand-rolled KRaft consensus engine (KIP-595 and KIP-996).

The engine is a pure, deterministic, sans-IO on_event state machine (core) over the QuorumState and Role model. The async controller::KraftController drives that state machine over the log::KraftLog and the real KIP-595 transport wire. This is Krabka’s live metadata consensus engine.

Re-exports

pub use controller::Activation;

pub use controller::KraftConfig;

pub use controller::KraftController;

pub use log::KraftLog;

pub use transport::Command;

pub use transport::Inbound;

pub use transport::MetadataFetchSlice;

pub use transport::NullPeerSender;

pub use transport::PeerSender;

pub use transport::QuorumStateSnapshot;

pub use transport::TimerTick;

Modules

action

Outputs from the consensus state machine. They are pure side-effect descriptions that the engine executes.

controller

The async KraftController consensus engine.

core

The KRaft quorum state machine: on_event(event, log, now) -> Vec<Action>.

event

Inputs to the consensus state machine.

log

KraftLog: the replicated metadata log behind the LogView seam.

role

The replica’s volatile role within the current epoch and its per-role state.

snapshot_fetch

Pure reassembly state machine for a follower that fetches a KIP-630 snapshot over FetchSnapshot (api key 59).

transport

Transport seam for the KraftController.

types

Core data types for the KRaft consensus state machine (KIP-595/996). Pure, sans-IO: no clock, no wire, no log bytes.

Structs

LogOffsetMetadata

A log position: an offset together with the leader epoch that produced it.

NodeId

A broker, node, replica, or controller identifier.

QuorumState

The durable quorum state: the logical content of the quorum-state file.

QuorumStateMachine

The hand-rolled KIP-595 + KIP-996 quorum state machine.

QuorumTimeouts

The two timer extents of a QuorumStateMachine, as Kafka’s QuorumConfig holds them.

ReplicaKey

Identifies a voter by node id and directory id, as Kafka’s ReplicaKey does.

SimInstant

A simulated or logical instant in milliseconds.

Enums

Action

Event

Role

Traits

LogView

Read-only view of the local replicated log that the state machine uses.

Type Aliases

Epoch

Consensus epoch, always non-negative; the wire leader epoch is krabka_ids::LeaderEpoch.