def _sign_transaction(self, prepared_tx):
acct = self._w3.eth.account.from_key(self._private_key)
try:
signed_tx = acct.sign_transaction(prepared_tx)
return signed_tx
except Exception:
raise UnableToSignTxError(
'You are trying to sign a non transaction type')
def sign_transaction(self, wif, transaction_to_sign):
secret_exponent = wif_to_secret_exponent(wif, self.allowable_wif_prefixes)
lookup = build_hash160_lookup([secret_exponent])
signed_transaction = transaction_to_sign.sign(lookup)
# Because signing failures silently continue, first check that the inputs are signed
for input in signed_transaction.txs_in:
if len(input.script) == 0:
logging.error('Unable to sign transaction. hextx=%s', signed_transaction.as_hex())
raise UnableToSignTxError('Unable to sign transaction')
return signed_transaction
def sign_transaction(self, wif, transaction_to_sign):
# try to sign the transaction.
self.w3 = Web3(HTTPProvider())
acct = self.w3.eth.account.from_key(wif)
try:
signed_tx = acct.sign_transaction(transaction_to_sign)
return signed_tx
except Exception as msg:
raise UnableToSignTxError(
'You are trying to sign a non transaction type')
def sign_transaction(self, wif, transaction_to_sign):
##try to sign the transaction.
if isinstance(transaction_to_sign, transactions.Transaction):
try:
raw_tx = rlp.encode(transaction_to_sign.sign(wif, self.netcode))
raw_tx_hex = encode_hex(raw_tx)
return raw_tx_hex
except Exception as msg:
return {'error': True, 'message': msg}
else:
raise UnableToSignTxError('You are trying to sign a non transaction type')
def transact(self, method, *argv):
"""
Sends a signed transaction on the blockchain and waits for a response.
If initialized with private key this class can sign the transaction.
In general, an external signer should be used in conjunction with
create_transaction() and broadcast_tx.
"""
if self._private_key is None:
raise UnableToSignTxError(
"This method is only available if a private key was passed upon initialization"
)
prepared_tx = self.create_transaction(method, *argv)
signed_tx = self._sign_transaction(prepared_tx)
txid = self.broadcast_transaction(signed_tx)
return txid