storj/storage/listkeys.go

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2019-01-24 20:15:10 +00:00
// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.
package storage
import (
"context"
)
// ListKeys returns keys starting from first and upto limit
// limit is capped to LookupLimit
func ListKeys(ctx context.Context, store KeyValueStore, first Key, limit int) (_ Keys, err error) {
defer mon.Task()(&ctx)(&err)
if limit <= 0 || limit > LookupLimit {
limit = LookupLimit
}
keys := make(Keys, 0, limit)
err = store.Iterate(ctx, IterateOptions{
First: first,
Recurse: true,
}, func(ctx context.Context, it Iterator) error {
var item ListItem
for ; limit > 0 && it.Next(ctx, &item); limit-- {
if item.Key == nil {
panic("nil key")
}
keys = append(keys, CloneKey(item.Key))
}
return nil
})
return keys, err
}
// ReverseListKeys returns keys starting from first and upto limit in reverse order
// limit is capped to LookupLimit
func ReverseListKeys(ctx context.Context, store KeyValueStore, first Key, limit int) (_ Keys, err error) {
defer mon.Task()(&ctx)(&err)
if limit <= 0 || limit > LookupLimit {
limit = LookupLimit
}
keys := make(Keys, 0, limit)
err = store.Iterate(ctx, IterateOptions{
First: first,
Recurse: true,
Reverse: true,
}, func(ctx context.Context, it Iterator) error {
var item ListItem
for ; limit > 0 && it.Next(ctx, &item); limit-- {
if item.Key == nil {
panic("nil key")
}
keys = append(keys, CloneKey(item.Key))
}
return nil
})
return keys, err
}