etcd

Documentation

Overview

Package etcd provides an implementation of master election based on etcd.

Index

• type Election
  • func (e *Election) Await(ctx context.Context) error
  • func (e *Election) Close(ctx context.Context) error
  • func (e *Election) Observe(ctx context.Context) (context.Context, error)
  • func (e *Election) Resign(ctx context.Context) error
• type Factory
  • func NewFactory(instanceID string, client *clientv3.Client, lockDir string) *Factory
  • func (f *Factory) NewElection(ctx context.Context, treeID int64) (election.Election, error)

Types

type Election

type Election struct {
	// contains filtered or unexported fields
}

Election is an implementation of election.Election based on etcd.

func (*Election) Await

func (e *Election) Await(ctx context.Context) error

Await blocks until the instance captures mastership.

func (*Election) Close

func (e *Election) Close(ctx context.Context) error

Close resigns and permanently stops participating in election. No other method should be called after Close.

func (*Election) Observe

func (e *Election) Observe(ctx context.Context) (context.Context, error)

Observe returns a "mastership context" which remains active until the instance stops being the master, or the passed in context is canceled.

func (*Election) Resign

func (e *Election) Resign(ctx context.Context) error

Resign releases mastership for this instance. The instance can be elected again using Await. Idempotent, might be useful to retry if fails.

type Factory

type Factory struct {
	// contains filtered or unexported fields
}

Factory creates Election instances.

func NewFactory

func NewFactory(instanceID string, client *clientv3.Client, lockDir string) *Factory

NewFactory builds an election factory that uses the given parameters. The passed in etcd client should remain valid for the lifetime of the object.

func (*Factory) NewElection

func (f *Factory) NewElection(ctx context.Context, treeID int64) (election.Election, error)

NewElection creates a specific Election instance.