minio/cmd/metacache-marker.go

93 lines
2.5 KiB
Go

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package cmd
import (
"context"
"fmt"
"strconv"
"strings"
"github.com/minio/minio/internal/logger"
)
// markerTagVersion is the marker version.
// Should not need to be updated unless a fundamental change is made to the marker format.
const markerTagVersion = "v2"
// parseMarker will parse a marker possibly encoded with encodeMarker
func (o *listPathOptions) parseMarker() {
s := o.Marker
if !strings.Contains(s, "[minio_cache:"+markerTagVersion) {
return
}
start := strings.LastIndex(s, "[")
o.Marker = s[:start]
end := strings.LastIndex(s, "]")
tag := strings.Trim(s[start:end], "[]")
tags := strings.Split(tag, ",")
for _, tag := range tags {
kv := strings.Split(tag, ":")
if len(kv) < 2 {
continue
}
switch kv[0] {
case "minio_cache":
if kv[1] != markerTagVersion {
break
}
case "id":
o.ID = kv[1]
case "return":
o.ID = mustGetUUID()
o.Create = true
case "p": // pool
v, err := strconv.ParseInt(kv[1], 10, 64)
if err != nil {
o.ID = mustGetUUID()
o.Create = true
continue
}
o.pool = int(v)
case "s": // set
v, err := strconv.ParseInt(kv[1], 10, 64)
if err != nil {
o.ID = mustGetUUID()
o.Create = true
continue
}
o.set = int(v)
default:
// Ignore unknown
}
}
}
// encodeMarker will encode a uuid and return it as a marker.
// uuid cannot contain '[', ':' or ','.
func (o listPathOptions) encodeMarker(marker string) string {
if o.ID == "" {
// Mark as returning listing...
return fmt.Sprintf("%s[minio_cache:%s,return:]", marker, markerTagVersion)
}
if strings.ContainsAny(o.ID, "[:,") {
logger.LogIf(context.Background(), fmt.Errorf("encodeMarker: uuid %s contained invalid characters", o.ID))
}
return fmt.Sprintf("%s[minio_cache:%s,id:%s,p:%d,s:%d]", marker, markerTagVersion, o.ID, o.pool, o.set)
}