Fallback to scanner to fetch confirmation info for external txs (#82)

* Fallback to esplora to fetch confirmation info for external txs

* Fallback to electrum to get tx confirmation info

internal/config/config.go

@@ -59,9 +59,6 @@ const (
 	// RootPathKey is the key to use a custom root path for the wallet,
 	// instead of the default m/84'/[1776|1]' (depending on network).
 	RootPathKey = "ROOT_PATH"
-	// EsploraUrlKey is the key for the esplora block esplorer consumed by the
-	// neutrino blockchain scanner.
-	EsploraUrlKey = "ESPLORA_URL"
 	// ElectrumUrlKey is the key for the electrum server endpoint consumed by the
 	// electrum blockchain scanner.
 	ElectrumUrlKey = "ELECTRUM_URL"
@@ -105,7 +102,6 @@ var (
 	defaultProfilerPort       = 18001
 	defaultStatsInterval      = 600 // 10 minutes
 	defaultUtxoExpiryDuration = 360 // 6 minutes (3 blocks)
-	defaultEsploraUrl         = "https://blockstream.info/liquid/api"
 	defaultElectrumUrl        = "ssl://blockstream.info:995"
 	defaultDustAmount         = uint64(450)
 
@@ -147,7 +143,6 @@ func init() {
 	vip.SetDefault(ProfilerPortKey, defaultProfilerPort)
 	vip.SetDefault(StatsIntervalKey, defaultStatsInterval)
 	vip.SetDefault(UtxoExpiryDurationKey, defaultUtxoExpiryDuration)
-	vip.SetDefault(EsploraUrlKey, defaultEsploraUrl)
 	vip.SetDefault(DbUserKey, "root")
 	vip.SetDefault(DbPassKey, "secret")
 	vip.SetDefault(DbHostKey, "127.0.0.1")

internal/core/application/transaction_service.go

@@ -71,6 +71,7 @@ func NewTransactionService(
 		format = fmt.Sprintf("transaction service: %s", format)
 		log.Debugf(format, a...)
 	}
+
 	svc := &TransactionService{
 		repoManager, bcScanner, net, utxoExpiryDuration, dustAmount, logFn,
 	}

internal/infrastructure/blockchain-scanner/electrum/service.go

@@ -29,6 +29,7 @@ type service struct {
 	utxoChannelByAccount         map[string]chan []*domain.Utxo
 	txChannelByAccount           map[string]chan *domain.Transaction
 	reportChannelByAccount       map[string]chan accountReport
+	blocksByHeight               map[uint64]blockInfo
 
 	log  func(format string, a ...interface{})
 	warn func(err error, format string, a ...interface{})
@@ -80,6 +81,7 @@ func NewService(args ServiceArgs) (ports.BlockchainScanner, error) {
 	accountAddressesByScriptHash := make(
 		map[string]map[string]domain.AddressInfo,
 	)
+	blocksByHeight := make(map[uint64]blockInfo)
 
 	client, err := args.client()
 	if err != nil {
@@ -98,7 +100,7 @@ func NewService(args ServiceArgs) (ports.BlockchainScanner, error) {
 	svc := &service{
 		client, db, lock, args.Network, accountAddressesByScriptHash,
 		utxoChannelByAccount, txChannelByAccount, reportChannelByAccount,
-		logFn, warnFn,
+		blocksByHeight, logFn, warnFn,
 	}
 	svc.db.registerEventHandler(svc.dbEventHandler)
 
@@ -382,10 +384,42 @@ func (s *service) GetTransactions(txids []string) ([]domain.Transaction, error)
 	}
 	txs := make([]domain.Transaction, 0, len(res))
 	for _, tx := range res {
+		txid := tx.TxHash().String()
+		scriptHash := calcScriptHash(hex.EncodeToString(tx.Outputs[0].Script))
+		history, _ := s.client.getScriptHashesHistory([]string{scriptHash})
+		var height int64
+		for _, tx := range history[scriptHash] {
+			if tx.Txid == txid {
+				height = tx.Height
+				break
+			}
+		}
+		var blockhash string
+		var blockheight uint64
+		var blocktime int64
+		if height > 0 {
+			info, ok := s.blocksByHeight[uint64(height)]
+			if ok {
+				blockhash = info.hash().String()
+				blockheight = info.Height
+				blocktime = info.timestamp()
+			} else {
+				info, _ := s.client.getBlocksInfo([]uint32{uint32(height)})
+				if len(info) > 0 {
+					s.blocksByHeight[uint64(height)] = info[0]
+					blockhash = info[0].hash().String()
+					blockheight = info[0].Height
+					blocktime = info[0].timestamp()
+				}
+			}
+		}
 		txHex, _ := tx.ToHex()
 		txs = append(txs, domain.Transaction{
-			TxID:  tx.TxHash().String(),
-			TxHex: txHex,
+			TxID:        txid,
+			TxHex:       txHex,
+			BlockHash:   blockhash,
+			BlockHeight: blockheight,
+			BlockTime:   blocktime,
 		})
 	}
 	return txs, nil