[#33] core/netmap: Define read-only storage interface

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
This commit is contained in:
Leonard Lyubich 2020-09-21 17:24:03 +03:00 committed by Alex Vanin
parent 030375af63
commit 3d25d6c217

View file

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package netmap
import (
"errors"
"github.com/nspcc-dev/neofs-api-go/pkg/netmap"
)
// Source is an interface that wraps
// basic network map receiving method.
type Source interface {
// GetNetMap reads the diff-th past network map from the storage.
// Calling with zero diff returns latest network map.
// It returns the pointer to requested network map and any error encountered.
//
// GetNetMap must return exactly one non-nil value.
// GetNetMap must return ErrNotFound if the network map is not in storage.
//
// Implementations must not retain the network map pointer and modify
// the network map through it.
GetNetMap(diff uint64) (*netmap.Netmap, error)
}
// ErrNotFound is the error returned when network map was not found in storage.
var ErrNotFound = errors.New("network map not found")
// GetLatestNetworkMap requests and returns latest network map from storage.
func GetLatestNetworkMap(src Source) (*netmap.Netmap, error) {
return src.GetNetMap(0)
}
// GetPreviousNetworkMap requests and returns previous from latest network map from storage.
func GetPreviousNetworkMap(src Source) (*netmap.Netmap, error) {
return src.GetNetMap(1)
}