storage

type ConfigStore interface {
	GetConfig(versionId string) (*protos.Configuration, StoreErr)
	PutConfig(cfg *protos.Configuration) StoreErr

	// GetAllConfigs returns all the `Configurations` that exist in the store, regardless of
	// the version, and whether they are used or not by an FSM.
	GetAllConfigs() []string

	// GetAllVersions returns the full `name:version` ID of all the Configurations whose
	// name matches `name`.
	GetAllVersions(name string) []string
}

type EventStore interface {
	GetEvent(id string, cfg string) (*protos.Event, StoreErr)
	PutEvent(event *protos.Event, cfg string, ttl time.Duration) StoreErr

	// AddEventOutcome adds the outcome of an event to the storage, given the `eventId` and the
	// "type" (`Configuration.Name`) of the FSM that received the event.
	//
	// Optionally, it will remove the outcome after a given `ttl` (time-to-live); use
	// `NeverExpire` to keep the outcome forever.
	AddEventOutcome(eventId string, cfgName string, response *protos.EventOutcome,
		ttl time.Duration) StoreErr

	// GetOutcomeForEvent returns the outcome of an event, given the `eventId` and the "type" of the
	// FSM that received the event.
	GetOutcomeForEvent(eventId string, cfgName string) (*protos.EventOutcome, StoreErr)
}

type FSMStore interface {
	// GetStateMachine will find the FSM with `id and that is configured via a `Configuration` whose
	// `name` matches `cfg` (without the `version`).
	GetStateMachine(id string, cfg string) (*protos.FiniteStateMachine, StoreErr)

	// PutStateMachine creates or updates the FSM whose `id` is given.
	// No further action is taken: no check that the referenced `Configuration` exists, and the
	// `state` SETs are not updated either: it is the caller's responsibility to call the
	// `UpdateState` method (possibly with an empty `oldState`, in the case of creation).
	PutStateMachine(id string, fsm *protos.FiniteStateMachine) StoreErr

	// GetAllInState looks up all the FSMs that are currently in the given `state` and
	// are configured with a `Configuration` whose name matches `cfg` (regardless of the
	// configuration's version).
	//
	// It returns the IDs for the FSMs.
	GetAllInState(cfg string, state string) []string

	// UpdateState will move the FSM's `id` from/to the respective Redis SETs.
	//
	// When creating or updating an FSM with `PutStateMachine`, the state SETs are not
	// modified; it is the responsibility of the caller to manage the FSM state appropriately
	// (or not, as the case may be).
	//
	// `oldState` may be empty in the case of a new FSM being created.
	UpdateState(cfgName string, id string, oldState string, newState string) StoreErr

	// TxProcessEvent processes an Event for the FSM in a transaction, guaranteeing that
	// there will be no races when updating the FSM state.
	TxProcessEvent(id, cfgName string, evt *protos.Event) StoreErr
}

type RedisStore struct {
	Timeout    time.Duration
	MaxRetries int
	// contains filtered or unexported fields
}

type StoreErr = error

type StoreManager interface {
	log.Loggable
	ConfigStore
	FSMStore
	EventStore
	SetTimeout(duration time.Duration)
	GetTimeout() time.Duration
	Health() error
}