election

Documentation

Index

• type Config
• type DlockLeaderManager
  • func NewDlockLeaderManager(dlm *dlock.LockManager, conf Config, elecKey string) *DlockLeaderManager
  • func (l *DlockLeaderManager) Await(ctx context.Context) bool
  • func (l *DlockLeaderManager) Campaign(ctx context.Context)
  • func (l *DlockLeaderManager) Extend(ctx context.Context) error
  • func (l *DlockLeaderManager) Identity() string
  • func (l *DlockLeaderManager) OnElected(cb ElectedCallback)
  • func (l *DlockLeaderManager) OnError(cb ErrorCallback)
  • func (l *DlockLeaderManager) OnOusted(cb OustedCallback)
  • func (l *DlockLeaderManager) Stop() error
• type ElectedCallback
• type ErrorCallback
• type LeaderManager
  • func MustNewLeaderManagerFromViper(dlm *dlock.LockManager, elecKey string) LeaderManager
• type LeaderStatus
• type OustedCallback

Types

type Config

type Config struct {
	// Leader election enabled or not?
	Enabled bool
	// Unique identifier for the leader
	ID string `default:"leader"`
	// Duration of the leader term
	Lease time.Duration `default:"1m"`
	// The time interval between retries of becoming the leader
	Retry time.Duration `default:"5s"`
	// The time interval trying to renew the leader term
	Renew time.Duration `default:"15s"`
}

Config holds the configuration for the leader election.

type DlockLeaderManager

type DlockLeaderManager struct {
	Config // election configuration
	// contains filtered or unexported fields
}

DlockLeaderManager manages the leader election process using distributed lock.

func NewDlockLeaderManager

func NewDlockLeaderManager(dlm *dlock.LockManager, conf Config, elecKey string) *DlockLeaderManager

NewDlockLeaderManager creates a new `LeaderManager` with the provided configuration and election key.

func (*DlockLeaderManager) Await

func (l *DlockLeaderManager) Await(ctx context.Context) bool

Await blocks until being elected as leader or context canceled.

func (*DlockLeaderManager) Campaign

func (l *DlockLeaderManager) Campaign(ctx context.Context)

Campaign starts the election process, which will run in a goroutine until contex canceled.

func (*DlockLeaderManager) Extend

func (l *DlockLeaderManager) Extend(ctx context.Context) error

Extend extends leadership lease.

func (*DlockLeaderManager) Identity

func (l *DlockLeaderManager) Identity() string

func (*DlockLeaderManager) OnElected

func (l *DlockLeaderManager) OnElected(cb ElectedCallback)

OnElected registers a callback function to be invoked on leader elected.

func (*DlockLeaderManager) OnError

func (l *DlockLeaderManager) OnError(cb ErrorCallback)

OnOusted registers a callback function to be invoked on leader ousted.

func (*DlockLeaderManager) OnOusted

func (l *DlockLeaderManager) OnOusted(cb OustedCallback)

OnOusted registers a callback function to be invoked on leader ousted.

func (*DlockLeaderManager) Stop

func (l *DlockLeaderManager) Stop() error

Stop stops the leader election process and resigns from the leadership if appliable.

type ElectedCallback

type ElectedCallback func(ctx context.Context, lm LeaderManager)

ElectedCallback is a type alias for the callback function executed upon leader elected.

type ErrorCallback

type ErrorCallback func(ctx context.Context, lm LeaderManager, err error)

ErrorCallback is a type alias for the callback function executed upon election error.

type LeaderManager

type LeaderManager interface {
	// Identity returns leader identity
	Identity() string
	// Wait until being elected as leader or context canceled
	Await(ctx context.Context) bool
	// Extend extends the leadership lease
	Extend(ctx context.Context) error
	// Campaign starts the leader election process
	Campaign(ctx context.Context)
	// Stop stops the leader election process
	Stop() error
	// OnElected registers a leader elected callback function.
	OnElected(cb ElectedCallback)
	// OnOusted registers a leader ousted callback function.
	OnOusted(cb OustedCallback)
	// OnError registers an election error callback function.
	OnError(cb ErrorCallback)
}

func MustNewLeaderManagerFromViper

func MustNewLeaderManagerFromViper(dlm *dlock.LockManager, elecKey string) LeaderManager

MustNewLeaderManagerFromViper creates a new LeaderManager with the given LockManager and election key.

type LeaderStatus

type LeaderStatus = int32

const (
	StatusInit LeaderStatus = iota
	StatusElected
	StatusOusted
)

type OustedCallback

type OustedCallback func(ctx context.Context, lm LeaderManager)

OustedCallback is a type alias for the callback function executed upon leader ousted.