gcs

Documentation

Overview

Package gcs contains an implementation of RaceDecider (plus helpers) for using Google Cloud Storage as a backend in leader-election.

Index

• type Decider
  • func NewDecider(client *storage.Client, bucket, object string, opts ...DeciderOpts) *Decider
  • func (d *Decider) ReadCurrent(ctx context.Context) (*entry.RaceEntry, error)
  • func (d *Decider) WriteEntry(ctx context.Context, rentry *entry.RaceEntry) (entry.LeaderToken, error)
• type DeciderOpts
  • func WithACLEntry(rule storage.ACLRule) DeciderOpts
  • func WithObjectReader(reader storage.ACLEntity) DeciderOpts

Types

type Decider

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

Decider implements leaderelection.RaceDecider using a specific object in a specific bucket for persistence

func NewDecider

func NewDecider(client *storage.Client, bucket, object string, opts ...DeciderOpts) *Decider

NewDecider creates a new gcs.Decider

func (*Decider) ReadCurrent

func (d *Decider) ReadCurrent(ctx context.Context) (*entry.RaceEntry, error)

ReadCurrent should provide the latest version of RaceEntry available and put any additional information needed to ensure transactional behavior in the Token-field.

func (*Decider) WriteEntry

func (d *Decider) WriteEntry(ctx context.Context, rentry *entry.RaceEntry) (entry.LeaderToken, error)

WriteEntry implementations should write the entry argument to stable-storage in a transactional-way such that only one contender wins per-election/term

type DeciderOpts

type DeciderOpts func(*deciderOptions)

DeciderOpts configures a GCS RaceDecider at construction-time

func WithACLEntry

func WithACLEntry(rule storage.ACLRule) DeciderOpts

WithACLEntry appends a ACL Rule to the ACL that will be set on new object versions written by this RaceDecider.

func WithObjectReader

func WithObjectReader(reader storage.ACLEntity) DeciderOpts

WithObjectReader appends a rule granting readonly access to the ACL entity argument to the ACL that will be set on new object versions written by this RaceDecider.