Goelect is an open-source Go (Golang) library for leader election. It is heavily influenced by the election component of the Raft implementation. For more details, you can refer to Raft Wiki.

Features

• Independent Operation: No third-party services are required. You don't need to set up or rely on external systems like ZooKeeper or etcd.
• Simplified Integration: Easy to integrate into your existing Golang projects with minimal configuration.
• Supports Novote role：The no-vote node does not participate in the election.
• Highly Available: Built to be fault-tolerant, suitable for systems that require high availability.

How to use

Config

// ElectConfig is a struct that represents the configuration for an election.
type ElectConfig struct {
    // Timeout for heartbeat messages, in milliseconds
    HeartBeatInterval uint
    // Timeout for election messages, in milliseconds
    ElectTimeout uint
    // Timeout for connecting to peers, in seconds
    ConnectTimeout uint
    // List of peers in the network
    Peers []Node
    // Node represents the information of this node
    Node Node
    // State callbacks
    CallBacks *StateCallBacks
    // Timeout for callbacks, in seconds
    CallBackTimeout int
}

Example

examples/onenode/node.go is a great example of using this goelect package.

Create an Elect instance:

e, err := goelect.NewElect(&goelect.ElectConfig{
		ElectTimeout:      200,
		HeartBeatInterval: 150,
		ConnectTimeout:    10,
		Peers:             peerNodes,
		// state transition callbacks
		CallBacks: &goelect.StateCallBacks{
			EnterLeader:    enterLeader,
			LeaveLeader:    leaveLeader,
			EnterFollower:  enterFollower,
			LeaveFollower:  leaveFollower,
			EnterCandidate: enterCandidate,
			LeaveCandidate: leaveCandidate,
		},
		// self node
		Node: goelect.Node{
			Address: *nodeAddress,
			ID:      *nodeAddress,
		},
	}, slog.Default())

Start the Elect:

err = e.Run()

This is everything we need to do :)