Class RaftNode<T>

Core Raft consensus node.

This class implements the Raft algorithm for leader election and log replication. It is transport-agnostic — the caller must wire up sendMessage to deliver RPCs, and call handleMessage when RPCs arrive.

Log indices are 1-based per the Raft paper.

Type Parameters

T = unknown

Hierarchy

RaftNode

Constructors

constructor

new RaftNode<T>(id, log, options?): RaftNode<T>
Type Parameters
- T = unknown
Parameters
- id: string
- log: RaftLog<T>
- Optional options: RaftNodeOptions
Returns RaftNode<T>
- Defined in raft/RaftNode.ts:79

Properties

`Private` commitIndex

commitIndex: number = 0

`Private` currentTerm

currentTerm: number = 0

`Private` destroyed

destroyed: boolean = false

`Private` `Readonly` electionTimeoutMax

electionTimeoutMax: number

`Private` `Readonly` electionTimeoutMin

electionTimeoutMin: number

`Private` electionTimer

electionTimer: number = null

`Private` `Readonly` eventListeners

eventListeners: EventListenerMap<T> = ...

`Private` `Readonly` heartbeatInterval

heartbeatInterval: number

`Private` heartbeatTimer

heartbeatTimer: number = null

`Readonly` id

id: string

`Private` lastApplied

lastApplied: number = 0

`Private` leaderId

leaderId: string = null

`Private` `Readonly` log

log: RaftLog<T>

`Private` matchIndex

matchIndex: Map<string, number> = ...

`Private` nextIndex

nextIndex: Map<string, number> = ...

`Private` peers

peers: string[] = []

`Private` role

role: RaftRole = 'follower'

sendMessage

sendMessage: ((toPeerId, message) => void) = ...

Type declaration

- (toPeerId, message): void
- Called by the node to send an RPC to a peer — must be wired up externally
  Parameters
  - toPeerId: string
  - message: RaftMessage<T>
  Returns void

`Private` votedFor

votedFor: string = null

`Private` votesReceived

votesReceived: Set<string> = ...

Methods

`Private` advanceCommitIndex

advanceCommitIndex(): void
Advance commitIndex if a majority of matchIndex values allow it

Returns void
- Defined in raft/RaftNode.ts:476

`Private` applyCommitted

applyCommitted(): void
Apply all committed but not-yet-applied entries

Returns void
- Defined in raft/RaftNode.ts:500

`Private` becomeCandidate

becomeCandidate(): void
Returns void
- Defined in raft/RaftNode.ts:222

`Private` becomeFollower

becomeFollower(): void
Returns void
- Defined in raft/RaftNode.ts:211

`Private` becomeLeader

becomeLeader(): void
Returns void
- Defined in raft/RaftNode.ts:253

`Private` clearElectionTimer

clearElectionTimer(): void
Returns void
- Defined in raft/RaftNode.ts:524

`Private` clearHeartbeatTimer

clearHeartbeatTimer(): void
Returns void
- Defined in raft/RaftNode.ts:531

destroy

destroy(): void
Stop all timers and clean up

Returns void
- Defined in raft/RaftNode.ts:203

`Private` emit

emit<E>(event, ...args): void
Type Parameters
- E extends keyof RaftNodeEvents<T>
Parameters
- event: E
- Rest ...args: Parameters<RaftNodeEvents<T>[E]>
Returns void
- Defined in raft/RaftNode.ts:549

getCommitIndex

getCommitIndex(): number
Get the commit index

Returns number
- Defined in raft/RaftNode.ts:177

getCurrentTerm

getCurrentTerm(): number
Get current term

Returns number
- Defined in raft/RaftNode.ts:167

getLeaderId

getLeaderId(): string
Get the current leader ID (null if unknown)

Returns string
- Defined in raft/RaftNode.ts:172

getRole

getRole(): RaftRole
Get current role

Returns RaftRole
- Defined in raft/RaftNode.ts:162

`Private` handleAppendEntries

handleAppendEntries(_fromPeerId, args): void
Parameters
- _fromPeerId: string
- args: AppendEntriesArgs<T>
Returns void
- Defined in raft/RaftNode.ts:346

`Private` handleAppendEntriesResult

handleAppendEntriesResult(result): void
Parameters
- result: AppendEntriesResult
Returns void
- Defined in raft/RaftNode.ts:426

handleMessage

handleMessage(fromPeerId, message): void
Handle an incoming Raft RPC message from a peer
Parameters
- fromPeerId: string
- message: RaftMessage<T>
Returns void
- Defined in raft/RaftNode.ts:133

`Private` handleRequestVote

handleRequestVote(_fromPeerId, args): void
Parameters
- _fromPeerId: string
- args: RequestVoteArgs
Returns void
- Defined in raft/RaftNode.ts:283

`Private` handleRequestVoteResult

handleRequestVoteResult(fromPeerId, result): void
Parameters
- fromPeerId: string
- result: RequestVoteResult
Returns void
- Defined in raft/RaftNode.ts:314

isLeader

isLeader(): boolean
Check if this node is the leader

Returns boolean
- Defined in raft/RaftNode.ts:182

`Private` isLogUpToDate

isLogUpToDate(candidateLastTerm, candidateLastIndex): boolean
Check if a candidate's log is at least as up-to-date as ours
Parameters
- candidateLastTerm: number
- candidateLastIndex: number
Returns boolean
- Defined in raft/RaftNode.ts:333

off

off<E>(event, listener): void
Remove an event listener
Type Parameters
- E extends keyof RaftNodeEvents<T>
Parameters
- event: E
- listener: RaftNodeEvents<T>[E]
Returns void
- Defined in raft/RaftNode.ts:195

on

on<E>(event, listener): void
Register an event listener
Type Parameters
- E extends keyof RaftNodeEvents<T>
Parameters
- event: E
- listener: RaftNodeEvents<T>[E]
Returns void
- Defined in raft/RaftNode.ts:187

`Private` persistState

persistState(): void
Returns void
- Defined in raft/RaftNode.ts:540

propose

propose(command): boolean
Submit a command to be replicated. Only succeeds on the leader.
Parameters
- command: T
Returns boolean
- Defined in raft/RaftNode.ts:116

`Private` resetElectionTimer

resetElectionTimer(): void
Returns void
- Defined in raft/RaftNode.ts:512

`Private` sendAppendEntriesTo

sendAppendEntriesTo(peer): void
Parameters
- peer: string
Returns void
- Defined in raft/RaftNode.ts:455

`Private` sendAppendEntriesToAll

sendAppendEntriesToAll(): void
Returns void
- Defined in raft/RaftNode.ts:449

start

start(peerIds): void
Start the node (begin election timer as follower)
Parameters
- peerIds: string[]
Returns void
- Defined in raft/RaftNode.ts:96

updatePeers

updatePeers(peerIds): void
Update the cluster membership dynamically (e.g. when peers join/leave)
Parameters
- peerIds: string[]
Returns void
- Defined in raft/RaftNode.ts:102

Class RaftNode<T>

Type Parameters

T = unknown

Hierarchy

Index

Constructors

Properties

Methods

Constructors

constructor

Type Parameters

T = unknown

Parameters

id: string

log: RaftLog<T>

Optional options: RaftNodeOptions

Returns RaftNode<T>

Properties

Private commitIndex

Private currentTerm

Private destroyed

Private Readonly electionTimeoutMax

Private Readonly electionTimeoutMin

Private electionTimer

Private Readonly eventListeners

Private Readonly heartbeatInterval

Private heartbeatTimer

Readonly id

Private lastApplied

Private leaderId

Private Readonly log

Private matchIndex

Private nextIndex

Private peers

Private role

sendMessage

Type declaration

Parameters

toPeerId: string

message: RaftMessage<T>

Returns void

Private votedFor

Private votesReceived

Methods

Private advanceCommitIndex

Returns void

Private applyCommitted

Returns void

Private becomeCandidate

Returns void

Private becomeFollower

Returns void

Private becomeLeader

Returns void

Private clearElectionTimer

Returns void

Private clearHeartbeatTimer

Returns void

destroy

Returns void

Private emit

Type Parameters

E extends keyof RaftNodeEvents<T>

Parameters

event: E

Rest ...args: Parameters<RaftNodeEvents<T>[E]>

Returns void

getCommitIndex

Returns number

getCurrentTerm

Returns number

getLeaderId

Returns string

getRole

Returns RaftRole

Private handleAppendEntries

Parameters

_fromPeerId: string

args: AppendEntriesArgs<T>

Returns void

`Optional` options: RaftNodeOptions

`Private` commitIndex

`Private` currentTerm

`Private` destroyed

`Private` `Readonly` electionTimeoutMax

`Private` `Readonly` electionTimeoutMin

`Private` electionTimer

`Private` `Readonly` eventListeners

`Private` `Readonly` heartbeatInterval

`Private` heartbeatTimer

`Readonly` id

`Private` lastApplied

`Private` leaderId

`Private` `Readonly` log

`Private` matchIndex

`Private` nextIndex

`Private` peers

`Private` role

`Private` votedFor

`Private` votesReceived

`Private` advanceCommitIndex

`Private` applyCommitted

`Private` becomeCandidate

`Private` becomeFollower

`Private` becomeLeader

`Private` clearElectionTimer

`Private` clearHeartbeatTimer

`Private` emit

`Rest` ...args: Parameters<RaftNodeEvents<T>[E]>

`Private` handleAppendEntries

`Private` handleAppendEntriesResult

`Private` handleRequestVote

`Private` handleRequestVoteResult

`Private` isLogUpToDate

`Private` persistState

`Private` resetElectionTimer

`Private` sendAppendEntriesTo

`Private` sendAppendEntriesToAll