improved kv metacore

internal/snapshot/wipe.go

@@ -0,0 +1,42 @@
+package snapshot
+
+import (
+	"fmt"
+
+	"github.com/metazla/meta-core/internal/storage"
+)
+
+// WipeScope picks which classes of data to clear.
+type WipeScope struct {
+	Metadata bool // file:* keys + file:__index__
+}
+
+// WipeResult reports what was cleared.
+type WipeResult struct {
+	MetadataDeleted int64 `json:"metadataDeleted"`
+}
+
+// Wiper clears metadata from Redis.
+type Wiper struct {
+	storage *storage.Client
+}
+
+func NewWiper(stor *storage.Client) *Wiper {
+	return &Wiper{storage: stor}
+}
+
+// Wipe applies the requested scope. Returns the count of files removed.
+func (w *Wiper) Wipe(scope WipeScope) (*WipeResult, error) {
+	if w.storage == nil || !w.storage.IsConnected() {
+		return nil, fmt.Errorf("storage not connected")
+	}
+	res := &WipeResult{}
+	if scope.Metadata {
+		n, err := w.storage.ClearAllMetadata()
+		if err != nil {
+			return nil, fmt.Errorf("clear metadata: %w", err)
+		}
+		res.MetadataDeleted = n
+	}
+	return res, nil
+}