election

Documentation

Index

• Variables
• type LeaderElectionCell
  • func NewLeaderElectionCell[T comparable](c agency.Agency, key []string, ttl time.Duration) *LeaderElectionCell[T]
  • func (l *LeaderElectionCell[T]) Read(ctx context.Context) (T, error)
  • func (l *LeaderElectionCell[T]) Resign(ctx context.Context) error
  • func (l *LeaderElectionCell[T]) Update(ctx context.Context, value T) (T, bool, time.Duration, error)
• type Lock
  • func NewLock(log Logger, api agency.Agency, key []string, id string, ttl time.Duration) (Lock, error)
• type Logger

Variables

var (
	// AlreadyLockedError indicates that the lock is already locked.
	AlreadyLockedError = errors.New("already locked")
	// NotLockedError indicates that the lock is not locked when trying to unlock.
	NotLockedError = errors.New("not locked")
)

Types

type LeaderElectionCell

type LeaderElectionCell[T comparable] struct {
	// contains filtered or unexported fields
}

func NewLeaderElectionCell

func NewLeaderElectionCell[T comparable](c agency.Agency, key []string, ttl time.Duration) *LeaderElectionCell[T]

func (*LeaderElectionCell[T]) Read

func (l *LeaderElectionCell[T]) Read(ctx context.Context) (T, error)

func (*LeaderElectionCell[T]) Resign

func (l *LeaderElectionCell[T]) Resign(ctx context.Context) error

Resign tries to resign leadership. If error is returned, caller should retry

func (*LeaderElectionCell[T]) Update

func (l *LeaderElectionCell[T]) Update(ctx context.Context, value T) (T, bool, time.Duration, error)

Update checks the current leader cell and if no leader is present it tries to put itself in there. Will return the value currently present, whether we are leader and a duration after which Updated should be called again.

type Lock

type Lock interface {
	// Lock tries to lock the lock.
	// If it is not possible to lock, an error is returned.
	// If the lock is already held by me, an error is returned.
	Lock(ctx context.Context) error

	// Unlock tries to unlock the lock.
	// If it is not possible to unlock, an error is returned.
	// If the lock is not held by me, an error is returned.
	Unlock(ctx context.Context) error

	// IsLocked return true if the lock is held by me.
	IsLocked() bool
}

Lock is an agency backed exclusive lock.

func NewLock

func NewLock(log Logger, api agency.Agency, key []string, id string, ttl time.Duration) (Lock, error)

NewLock creates a new lock on the given key.

type Logger

type Logger interface {
	Errorf(msg string, args ...interface{})
}

Logger abstracts a logger.