wal

type Commit ¶

type Commit func() error

Commit drops a logged event once its operation has succeeded.

type EventHandler ¶

type EventHandler interface {
	Typ() string
	Encode(any) ([]byte, error)
	Decode([]byte) (any, error)
	Handle(context.Context, any) error
}

type Hydro ¶

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

Hydro journals events into the eru store, under the prefix of this instance's service address.

func NewHydro(ctx context.Context, store Store, address string, config coretypes.Config) (*Hydro, error)

func (h *Hydro) Log(eventyp string, item any) (Commit, error)

func (h *Hydro) Recover(ctx context.Context)

func (h *Hydro) Register(handler EventHandler)

func (h *Hydro) Takeover(ctx context.Context, live []string)

type HydroEvent ¶

type HydroEvent struct {
	Type string `json:"type"`
	Item []byte `json:"item"`
}

HydroEvent is one journal entry: what happened and the handler's own payload.

func NewHydroEvent(typ string, item []byte) *HydroEvent

func (e HydroEvent) Encode() ([]byte, error)

type Store ¶ added in v0.1.1

type Store interface {
	Put(ctx context.Context, data map[string]string) error
	Delete(ctx context.Context, keys []string) error
	GetPrefix(ctx context.Context, prefix string, limit int64) (map[string]string, error)
	ListPrefix(ctx context.Context, prefix string) ([]string, error)
	CreateLock(key string, ttl time.Duration) (lock.DistributedLock, error)
}

Store is the part of the eru store a journal writes through.

type WAL ¶

type WAL interface {
	Register(EventHandler)
	Recover(context.Context)
	Takeover(ctx context.Context, live []string)
	Log(string, any) (Commit, error)
}

WAL logs an event before its operation runs and replays the unfinished ones on recovery.