go code can read and write chunk manifest

weed/storage/needle/volume_ttl.go

@@ -1,11 +1,12 @@
 package needle
 
 import (
+	"fmt"
 	"strconv"
 )
 
 const (
-	//stored unit types
+	// stored unit types
 	Empty byte = iota
 	Minute
 	Hour
@@ -139,3 +140,10 @@ func (t TTL) Minutes() uint32 {
 	}
 	return 0
 }
+
+func SecondsToTTL(seconds int32) string {
+	if seconds == 0 {
+		return ""
+	}
+	return fmt.Sprintf("%dm", seconds/60)
+}