eventstate

type FindFailureQuery struct {
	// HandlerNames defines the filter for the handler names in a query for unhandled events.
	HandlerNames []string
}

type FindUnhandledQuery struct {
	// HandlerNames defines the filter for the handler names in a query for unhandled events.
	HandlerNames []string
}

type HandleFailure struct {
	// EventID is an identifier of the related event.
	EventID string
	// HandlerName defines the name of the handler for which the handling failed.
	HandlerName string
	// Err keeps the error information.
	Err string
	// ErrCode keeps the code of the error.
	ErrCode cgerrors.ErrorCode
	// RetryNo is the number of the retries to handle given event.
	RetryNo int
	// Timestamp of the failure.
	Timestamp time.Time
}

type HandleSearcher interface {
	// FindUnhandledEvents finds all unhandled events for given handler.
	FindUnhandledEvents(ctx context.Context, query FindUnhandledQuery) ([]Unhandled, error)

	// FindEventHandleFailures finds the handle failures for given handler name.
	FindEventHandleFailures(ctx context.Context, query FindFailureQuery) ([]HandleFailure, error)
}

type Handler struct {
	// Name is the unique, human-readable name for the event handler.
	Name string
	// EventTypes defines the type of the event handled by given handler.
	EventTypes []string
}

type HandlerRegistry interface {
	// RegisterHandlers registers the information about event handler.
	// This function should be done during migration of the event handler.
	RegisterHandlers(ctx context.Context, eventHandlers ...Handler) error

	// ListHandlers list the handlers for the
	ListHandlers(ctx context.Context) ([]Handler, error)
}

type StateHandler interface {
	// StartHandling starts handling given event by the handler with a name = handlerName.
	StartHandling(ctx context.Context, eventID, handlerName string) error

	// FinishHandling finishes handling given event by the handlerName.
	FinishHandling(ctx context.Context, eventID, handlerName string) error

	// HandlingFailed finishes handling given event by the handlerName.
	HandlingFailed(ctx context.Context, eventID, handlerName string, handleErr error) error
}

type Unhandled struct {
	// EventUD is an identifier of the related event.
	EventID string
	// HandlerName defines the name of the handler where an event was not yet handled.
	HandlerName string
}