def _swap_close(self, context, signer_pubkey, swap_close_payload):
"""
Bob or Alice closes the swap by providing the secret key which matches secret lock.
Requires "is_approved = True"
Requires hash of secret key to match secret lock
"""
swap_info = self.get_swap_info_from_swap_id(context,
swap_close_payload.swap_id)
if not swap_info.secret_lock:
raise InvalidTransaction(
'Secret lock is required to close the swap!')
if hash256(swap_close_payload.secret_key) != swap_info.secret_lock:
raise InvalidTransaction(
'Secret key doesn\'t match specified secret lock!')
if not swap_info.is_approved:
raise InvalidTransaction(
'Transaction cannot be closed before it\'s approved.')
transfer_payload = AccountClient.get_transfer_payload(
swap_info.receiver_address, swap_info.amount)
token_updated_state = AccountHandler._transfer_from_address(
context, ZERO_ADDRESS, transfer_payload)
swap_info.is_closed = True
return {**self.get_state_update(swap_info), **token_updated_state}
def _swap_expire(self, context, signer_pubkey, swap_expire_payload):
"""
Transaction initiator (Alice) decides to withdraw deposit in 24 hours, or Bob in 48 hours
"""
swap_info = self.get_swap_info_from_swap_id(
context, swap_expire_payload.swap_id)
if AccountHandler.make_address_from_data(
signer_pubkey) != swap_info.sender_address:
raise InvalidTransaction(
'Signer is not the one who opened the swap.')
now = datetime.datetime.utcnow()
created_at = self.get_datetime_from_timestamp(swap_info.created_at)
time_delta = INITIATOR_TIME_DELTA_LOCK if swap_info.is_initiator else NON_INITIATOR_TIME_DELTA_LOCK
if (created_at + time_delta) > now:
intiator_name = "initiator" if swap_info.is_initiator else "non initiator"
raise InvalidTransaction(
'Swap {} needs to wait {} hours since timestamp: {} to withdraw.'
.format(intiator_name, INTIATOR_TIME_LOCK,
swap_info.created_at))
swap_info.is_closed = True
transfer_payload = AccountClient.get_transfer_payload(
swap_info.sender_address, swap_info.amount)
token_updated_state = AccountHandler._transfer_from_address(
context, ZERO_ADDRESS, transfer_payload)
return {**self.get_state_update(swap_info), **token_updated_state}
def _swap_init(self, context, signer_pubkey, swap_init_payload):
"""
if SecretLockOptionalBob is provided, Bob uses _swap_init to respond to requested swap
Otherwise, Alice uses _swap_init to request a swap and thus, Bob can't receive funds until Alice "approves".
"""
LOGGER.info("0. Check if swap ID already exists")
# 0. Check if swap ID already exists
if self.get_swap_info_from_swap_id(context,
swap_init_payload.swap_id,
to_raise_exception=False):
raise InvalidTransaction(
'Atomic swap ID has already been taken, please use a different one!'
)
# END
swap_info = AtomicSwapInfo()
swap_info.swap_id = swap_init_payload.swap_id
swap_info.is_closed = False
swap_info.amount = swap_init_payload.amount
swap_info.created_at = swap_init_payload.created_at
swap_info.email_address_encrypted_optional = swap_init_payload.email_address_encrypted_by_initiator
swap_info.sender_address = AccountHandler.make_address_from_data(
signer_pubkey)
swap_info.sender_address_non_local = swap_init_payload.sender_address_non_local
swap_info.receiver_address = swap_init_payload.receiver_address
if not AccountHandler.is_handler_address(swap_info.receiver_address):
raise InvalidTransaction(
'Receiver address is not of a Token type.')
LOGGER.info("1. Ensure transaction initiated within an hour")
# 1. Ensure transaction initiated within an hour
swap_info.secret_lock = swap_init_payload.secret_lock_by_solicitor
created_at = self.get_datetime_from_timestamp(swap_info.created_at)
now = datetime.datetime.utcnow()
if not (now - datetime.timedelta(hours=1) < created_at < now):
raise InvalidTransaction(
'Transaction is created a long time ago or timestamp is assigned set.'
)
# END
LOGGER.info("2. Check weather the sender is Alice")
# 2. Check weather the sender is Alice:
swap_info.is_initiator = not swap_init_payload.secret_lock_by_solicitor
# if Bob
swap_info.is_approved = not swap_info.is_initiator
# END
# 3. Transfer funds to zero address.
LOGGER.info("3. Transfer funds to zero address")
commission = int(_get_setting_value(context, SETTINGS_SWAP_COMMISSION))
if commission < 0:
raise InvalidTransaction('Wrong commission address.')
LOGGER.info("4. Get sender's account {}".format(
swap_info.sender_address))
account = get_account_by_address(context, swap_info.sender_address)
total_amount = swap_info.amount + commission
if account.balance < total_amount:
raise InvalidTransaction(
'Not enough balance to perform the transaction in '
'the amount (with a commission) {}.'.format(total_amount))
transfer_payload = AccountClient.get_transfer_payload(
ZERO_ADDRESS, total_amount)
token_updated_state = AccountHandler._transfer_from_address(
context, swap_info.sender_address, transfer_payload)
LOGGER.info("Save state")
return {**self.get_state_update(swap_info), **token_updated_state}
