status-go/services/shhext/dedup/deduplicator.go

53 lines
1.5 KiB
Go

package dedup
import (
"github.com/ethereum/go-ethereum/log"
whisper "github.com/status-im/whisper/whisperv6"
"github.com/syndtr/goleveldb/leveldb"
)
type keyPairProvider interface {
SelectedKeyPairID() string
}
// Deduplicator filters out already received messages for a current filter.
// It keeps a limited cache of the messages.
type Deduplicator struct {
keyPairProvider keyPairProvider
cache *cache
log log.Logger
}
// NewDeduplicator creates a new deduplicator
func NewDeduplicator(keyPairProvider keyPairProvider, db *leveldb.DB) *Deduplicator {
return &Deduplicator{
log: log.New("package", "status-go/services/sshext.deduplicator"),
keyPairProvider: keyPairProvider,
cache: newCache(db),
}
}
// Deduplicate receives a list of whisper messages and
// returns the list of the messages that weren't filtered previously for the
// specified filter.
func (d *Deduplicator) Deduplicate(messages []*whisper.Message) []*whisper.Message {
result := make([]*whisper.Message, 0)
for _, message := range messages {
if has, err := d.cache.Has(d.keyPairProvider.SelectedKeyPairID(), message); !has {
if err != nil {
d.log.Error("error while deduplicating messages: search cache failed", "err", err)
}
result = append(result, message)
}
}
return result
}
// AddMessages adds a message to the deduplicator DB, so it will be filtered
// out.
func (d *Deduplicator) AddMessages(messages []*whisper.Message) error {
return d.cache.Put(d.keyPairProvider.SelectedKeyPairID(), messages)
}