Use tx index event parameter

We used to have our own counter for encrypted txs added to the sequencer
contract. Under normal circumstances, this value is the same as the
`txIndex` parameter on the TransactionSubmittedEvent. Using the latter
is more resistant to reorgs, so we use that now.

Author: jannikluhn

rolling-shutter/keyperimpl/gnosis/database/gnosiskeyper.sqlc.gen.go

@@ -11,11 +11,18 @@ INSERT INTO transaction_submitted_event (
     gas_limit
 )
 VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9)
-ON CONFLICT DO NOTHING;
+ON CONFLICT (index, eon) DO UPDATE SET
+block_number = $2,
+block_hash = $3,
+tx_index = $4,
+log_index = $5,
+identity_prefix = $7,
+sender = $8,
+gas_limit = $9;
 
 -- name: GetTransactionSubmittedEvents :many
 SELECT * FROM transaction_submitted_event
-WHERE eon = $1 AND index >= $2
+WHERE eon = $1 AND index >= $2 AND index < $2 + $3
 ORDER BY index ASC
 LIMIT $3;
 

rolling-shutter/keyperimpl/gnosis/database/sql/queries/gnosiskeyper.sql

@@ -154,20 +154,8 @@ func (s *SequencerSyncer) insertTransactionSubmittedEvents(
 	queries := database.New(tx)
 	nextEventIndices := make(map[uint64]int64)
 	for _, event := range events {
-		nextEventIndex, ok := nextEventIndices[event.Eon]
-		if !ok {
-			nextEventIndexFromDB, err := queries.GetTransactionSubmittedEventCount(ctx, int64(event.Eon))
-			if err == pgx.ErrNoRows {
-				nextEventIndexFromDB = 0
-			} else if err != nil {
-				return errors.Wrapf(err, "failed to query count of transaction submitted events for eon %d", event.Eon)
-			}
-			nextEventIndices[event.Eon] = nextEventIndexFromDB
-			nextEventIndex = nextEventIndexFromDB
-		}
-
 		_, err := queries.InsertTransactionSubmittedEvent(ctx, database.InsertTransactionSubmittedEventParams{
-			Index:          nextEventIndex,
+			Index:          int64(event.TxIndex),
 			BlockNumber:    int64(event.Raw.BlockNumber),
 			BlockHash:      event.Raw.BlockHash[:],
 			TxIndex:        int64(event.Raw.TxIndex),
@@ -180,10 +168,10 @@ func (s *SequencerSyncer) insertTransactionSubmittedEvents(
 		if err != nil {
 			return errors.Wrap(err, "failed to insert transaction submitted event into db")
 		}
-		metricsLatestTxSubmittedEventIndex.WithLabelValues(fmt.Sprint(event.Eon)).Set(float64(nextEventIndex))
+		metricsLatestTxSubmittedEventIndex.WithLabelValues(fmt.Sprint(event.Eon)).Set(float64(event.TxIndex))
 		nextEventIndices[event.Eon]++
 		log.Debug().
-			Int64("index", nextEventIndex).
+			Uint64("index", event.TxIndex).
 			Uint64("block", event.Raw.BlockNumber).
 			Uint64("eon", event.Eon).
 			Hex("identityPrefix", event.IdentityPrefix[:]).