Ejemplo n.º 1
0
// createBtcWithdrawTx create withdraw transaction.
// amount is the number of coins that want to withdraw.
// toAddr is the address that the coins will be sent to.
func createBtcWithdrawTx(egn engine.Exchange, amount uint64, toAddr string) (*BtcTxResult, error) {
	uxs, err := egn.ChooseUtxos(bitcoin.Type, amount+egn.GetBtcFee(), ChooseUtxoTm)
	if err != nil {
		return nil, err
	}
	utxos := uxs.([]bitcoin.Utxo)

	for _, u := range utxos {
		logger.Debug("using utxos: txid:%s vout:%d addr:%s", u.GetTxid(), u.GetVout(), u.GetAddress())
	}

	var success bool
	defer func() {
		if !success {
			// put utxos back to pool if withdraw failed.
			go func() { egn.PutUtxos(bitcoin.Type, utxos) }()
		}
	}()

	var totalAmounts uint64
	for _, u := range utxos {
		totalAmounts += u.GetAmount()
	}
	fee := egn.GetBtcFee()
	outAddrs := []bitcoin.TxOut{}
	chgAmt := totalAmounts - fee - amount
	chgAddr := ""
	if chgAmt > 0 {
		// generate a change address
		chgAddr = egn.GetNewAddress(bitcoin.Type)
		outAddrs = append(outAddrs,
			bitcoin.TxOut{Addr: toAddr, Value: amount},
			bitcoin.TxOut{Addr: chgAddr, Value: chgAmt})
	} else {
		outAddrs = append(outAddrs, bitcoin.TxOut{Addr: toAddr, Value: amount})
	}
	// change utxo to UtxoWithkey
	utxoKeys, err := makeBtcUtxoWithkeys(utxos, egn)
	if err != nil {
		return nil, err
	}

	logger.Debug("creating transaction...")
	tx, err := bitcoin.NewTransaction(utxoKeys, outAddrs)
	if err != nil {
		logger.Error(err.Error())
		return nil, err
	}
	success = true
	rlt := BtcTxResult{
		Tx:         tx,
		UsingUtxos: utxos[:],
		ChangeAddr: chgAddr,
	}
	return &rlt, nil
}
Ejemplo n.º 2
0
func createBtcTxInOut(ee engine.Exchange, a account.Accounter, amount uint64, outAddr string) (*txInOutResult, error) {
	var rlt txInOutResult
	// verify the outAddr
	if _, err := cipher.BitcoinDecodeBase58Address(outAddr); err != nil {
		return nil, errors.New("invalid bitcoin address")
	}

	var err error
	// decrease balance and check if the balance is sufficient.
	if err := a.DecreaseBalance("bitcoin", amount+ee.GetBtcFee()); err != nil {
		return nil, err
	}

	var utxos []bitcoin.Utxo

	// choose sufficient utxos.
	uxs, err := ee.ChooseUtxos("bitcoin", amount+ee.GetBtcFee(), ChooseUtxoTm)
	if err != nil {
		return nil, err
	}
	utxos = uxs.([]bitcoin.Utxo)

	for _, u := range utxos {
		logger.Debug("using utxos: txid:%s vout:%d addr:%s", u.GetTxid(), u.GetVout(), u.GetAddress())
		rlt.TxIns = append(rlt.TxIns, coin.TxIn{
			Txid: u.GetTxid(),
			Vout: u.GetVout(),
		})
	}

	var totalAmounts uint64
	for _, u := range utxos {
		totalAmounts += u.GetAmount()
	}
	fee := ee.GetBtcFee()
	txOuts := []bitcoin.TxOut{}
	chgAmt := totalAmounts - fee - amount
	chgAddr := ""
	if chgAmt > 0 {
		// generate a change address
		chgAddr = ee.GetNewAddress(bitcoin.Type)
		txOuts = append(txOuts,
			bitcoin.TxOut{Addr: outAddr, Value: amount},
			bitcoin.TxOut{Addr: chgAddr, Value: chgAmt})
	} else {
		txOuts = append(txOuts, bitcoin.TxOut{Addr: outAddr, Value: amount})
	}

	rlt.TxOuts = txOuts
	rlt.Teardown = func() {
		a.IncreaseBalance(bitcoin.Type, amount+ee.GetBtcFee())
		ee.PutUtxos(bitcoin.Type, utxos)
	}

	return &rlt, nil
}