storj/storage/redis/util.go
Egon Elbre b8c7dcbf7b certificate: improve gob migration
`storage.KeyValueStore` requires ordered iteration, which redis
doesn't support natively. This would require loading all the keys
into memory and then processing them, rather than iterating over them
one-by-one.

This adds a temporary `IterateUnordered` to handle the migrations
more gracefully.

Change-Id: I55b763500523077c7ab8fdfad175c32cc7788e47
2023-02-01 10:21:48 +00:00

106 lines
2.1 KiB
Go

// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.
package redis
import (
"bytes"
"context"
"sort"
"github.com/go-redis/redis/v8"
"storj.io/storj/storage"
)
func escapeMatch(match []byte) []byte {
start := 0
escaped := []byte{}
for i, b := range match {
switch b {
case '?', '*', '[', ']', '\\':
escaped = append(escaped, match[start:i]...)
escaped = append(escaped, '\\', b)
start = i + 1
}
}
if start == 0 {
return match
}
return append(escaped, match[start:]...)
}
// sortAndCollapse sorts items and combines elements based on Delimiter.
// items will be reused and modified.
func sortAndCollapse(items storage.Items, prefix []byte) storage.Items {
sort.Sort(items)
result := items[:0]
var currentPrefix []byte
var prefixed bool
for _, item := range items {
if prefixed {
if bytes.HasPrefix(item.Key, currentPrefix) {
continue
}
prefixed = false
}
if p := bytes.IndexByte(item.Key[len(prefix):], storage.Delimiter); p >= 0 {
currentPrefix = item.Key[:len(prefix)+p+1]
prefixed = true
result = append(result, storage.ListItem{
Key: currentPrefix,
IsPrefix: true,
})
} else {
result = append(result, item)
}
}
return result
}
// StaticIterator implements an iterator over list of items.
type StaticIterator struct {
Items storage.Items
Index int
}
// Next returns the next item from the iterator.
func (it *StaticIterator) Next(ctx context.Context, item *storage.ListItem) bool {
if it.Index >= len(it.Items) {
return false
}
*item = it.Items[it.Index]
it.Index++
return true
}
// ScanIterator iterates over scan command items.
type ScanIterator struct {
db *redis.Client
it *redis.ScanIterator
}
// Next returns the next item from the iterator.
func (it *ScanIterator) Next(ctx context.Context, item *storage.ListItem) bool {
ok := it.it.Next(ctx)
if !ok {
return false
}
key := it.it.Val()
value, err := it.db.Get(ctx, key).Bytes()
if err != nil {
return false
}
item.Key = storage.Key(key)
item.Value = storage.Value(value)
item.IsPrefix = false
return true
}