Files
eventstore/badger/delete.go

86 lines
1.8 KiB
Go

package badger
import (
"context"
"encoding/hex"
"log"
"github.com/dgraph-io/badger/v4"
"github.com/nbd-wtf/go-nostr"
nostr_binary "github.com/nbd-wtf/go-nostr/binary"
)
var serialDelete uint32 = 0
func (b *BadgerBackend) DeleteEvent(ctx context.Context, evt *nostr.Event) error {
deletionHappened := false
err := b.Update(func(txn *badger.Txn) error {
idx := make([]byte, 1, 5)
idx[0] = rawEventStorePrefix
// query event by id to get its idx
id, _ := hex.DecodeString(evt.ID)
prefix := make([]byte, 1+32)
prefix[0] = indexIdPrefix
copy(prefix[1:], id)
opts := badger.IteratorOptions{
PrefetchValues: false,
}
it := txn.NewIterator(opts)
it.Seek(prefix)
if it.ValidForPrefix(prefix) {
idx = append(idx, it.Item().Key()[1+32:]...)
}
it.Close()
// if no idx was found, end here, this event doesn't exist
if len(idx) == 1 {
return nil
}
// fetch the event
item, err := txn.Get(idx)
if err != nil {
return err
}
item.Value(func(val []byte) error {
evt := &nostr.Event{}
if err := nostr_binary.Unmarshal(val, evt); err != nil {
return err
}
// set this so we'll run the GC later
deletionHappened = true
// calculate all index keys we have for this event and delete them
for _, k := range getIndexKeysForEvent(evt, idx[1:]) {
if err := txn.Delete(k); err != nil {
return err
}
}
// delete the raw event
return txn.Delete(idx)
})
return nil
})
if err != nil {
return err
}
// after deleting, run garbage collector (sometimes)
if deletionHappened {
serialDelete = (serialDelete + 1) % 256
if serialDelete == 0 {
if err := b.RunValueLogGC(0.8); err != nil && err != badger.ErrNoRewrite {
log.Println("badger gc errored:" + err.Error())
}
}
}
return nil
}