feat: handle unexpected unbonding tx (#102)

internal/services/delegation.go

@@ -274,6 +274,10 @@ func (s *Service) processBTCDelegationInclusionProofReceivedEvent(
 	return nil
 }
 
+// TODO: Indexer doesn't need to intercept processBTCDelegationUnbondedEarlyEvent
+// as the unbonding tx will be discovered by the btc notifier
+// we are keeping it for now to avoid breaking changes, but if the btc notifier has already identified
+// then this event will be silently ignored with help of validateBTCDelegationUnbondedEarlyEvent
 func (s *Service) processBTCDelegationUnbondedEarlyEvent(
 	ctx context.Context, event abcitypes.Event, bbnBlockHeight int64,
 ) *types.Error {
@@ -336,6 +340,7 @@ func (s *Service) processBTCDelegationUnbondedEarlyEvent(
 
 	log.Debug().
 		Str("staking_tx", unbondedEarlyEvent.StakingTxHash).
+		Stringer("current_state", delegation.State).
 		Stringer("new_state", types.StateUnbonding).
 		Str("early_unbonding_start_height", unbondedEarlyEvent.StartHeight).
 		Str("unbonding_time", strconv.FormatUint(uint64(delegation.UnbondingTime), 10)).
@@ -353,6 +358,15 @@ func (s *Service) processBTCDelegationUnbondedEarlyEvent(
 		db.WithSubState(subState),
 		db.WithBbnHeight(bbnBlockHeight),
 	); err != nil {
+		if db.IsNotFoundError(err) {
+			// maybe the btc notifier has already identified the unbonding tx and updated the state
+			log.Debug().
+				Str("staking_tx", delegation.StakingTxHashHex).
+				Interface("qualified_states", types.QualifiedStatesForUnbondedEarly()).
+				Msg("delegation not in qualified states for early unbonding update")
+			return nil
+		}
+
 		return types.NewError(
 			http.StatusInternalServerError,
 			types.InternalServiceError,

internal/services/delegation_helpers.go

@@ -18,23 +18,15 @@ import (
 func (s *Service) registerUnbondingSpendNotification(
 	ctx context.Context,
 	delegation *model.BTCDelegationDetails,
-) *types.Error {
+) error {
 	unbondingTxBytes, parseErr := hex.DecodeString(delegation.UnbondingTx)
 	if parseErr != nil {
-		return types.NewError(
-			http.StatusInternalServerError,
-			types.InternalServiceError,
-			fmt.Errorf("failed to decode unbonding tx: %w", parseErr),
-		)
+		return fmt.Errorf("failed to decode unbonding tx: %w", parseErr)
 	}
 
 	unbondingTx, parseErr := bbn.NewBTCTxFromBytes(unbondingTxBytes)
 	if parseErr != nil {
-		return types.NewError(
-			http.StatusInternalServerError,
-			types.InternalServiceError,
-			fmt.Errorf("failed to parse unbonding tx: %w", parseErr),
-		)
+		return fmt.Errorf("failed to parse unbonding tx: %w", parseErr)
 	}
 
 	log.Debug().