nonce handling improvements (#26)

ethtxmanager/ethtxmanager.go

@@ -145,14 +145,42 @@ func pendingL1Txs(URL string, from common.Address, httpHeaders map[string]string
 	return mTxs, nil
 }
 
+// getTxNonce get the nonce for the given account
+func (c *Client) getTxNonce(ctx context.Context, from common.Address) (uint64, error) {
+	// Get created transactions from the database for the given account
+	createdTxs, err := c.storage.GetByStatus(ctx, []MonitoredTxStatus{MonitoredTxStatusCreated})
+	if err != nil {
+		return 0, fmt.Errorf("failed to get created monitored txs: %w", err)
+	}
+
+	var nonce uint64
+	if len(createdTxs) > 0 {
+		// if there are pending txs, we adjust the nonce accordingly
+		for _, createdTx := range createdTxs {
+			if createdTx.Nonce > nonce {
+				nonce = createdTx.Nonce
+			}
+		}
+
+		nonce++
+	} else {
+		// if there are no pending txs, we get the pending nonce from the etherman
+		if nonce, err = c.etherman.PendingNonce(ctx, from); err != nil {
+			return 0, fmt.Errorf("failed to get pending nonce: %w", err)
+		}
+	}
+
+	return nonce, nil
+}
+
 // Add a transaction to be sent and monitored
 func (c *Client) Add(ctx context.Context, to *common.Address, forcedNonce *uint64, value *big.Int, data []byte) (common.Hash, error) {
 	var nonce uint64
 	var err error
 
 	if forcedNonce == nil {
 		// get next nonce
-		nonce, err = c.etherman.CurrentNonce(ctx, c.from)
+		nonce, err = c.getTxNonce(ctx, c.from)
 		if err != nil {
 			err := fmt.Errorf("failed to get current nonce: %w", err)
 			log.Errorf(err.Error())
@@ -703,7 +731,7 @@ func (c *Client) reviewMonitoredTx(ctx context.Context, mTx *monitoredTx, mTxLog
 // causing possible side effects and wasting resources.
 func (c *Client) reviewMonitoredTxNonce(ctx context.Context, mTx *monitoredTx, mTxLogger *log.Logger) error {
 	mTxLogger.Debug("reviewing nonce")
-	nonce, err := c.etherman.CurrentNonce(ctx, mTx.From)
+	nonce, err := c.getTxNonce(ctx, mTx.From)
 	if err != nil {
 		err := fmt.Errorf("failed to load current nonce for acc %v: %w", mTx.From.String(), err)
 		mTxLogger.Errorf(err.Error())