def _parse_post(req_class: T) -> T:
json = request.get_json()
if not json:
raise exceptions.ApiException("JSON payload expected")
try:
return req_class.Schema().load(json) # type: ignore
except marshmallow.ValidationError as ex:
raise exceptions.InvalidRequest(**ex.messages)
def _parse_post(req_class: T) -> T:
json = request.get_json()
if not json:
raise exceptions.ApiException("JSON payload expected")
req, errors = req_class.Schema().load(json) # type: ignore
if errors:
raise exceptions.InvalidRequest(**errors)
return req
def process_payment(iou_dict: dict, pathfinding_service: PathfindingService):
if pathfinding_service.service_fee == 0:
return
if iou_dict is None:
raise exceptions.MissingIOU
# Basic IOU validity checks
iou, errors = IOU.Schema().load(iou_dict)
if errors:
raise exceptions.InvalidRequest(**errors)
if iou.receiver != pathfinding_service.address:
raise exceptions.WrongIOURecipient(
expected=pathfinding_service.address)
if not iou.is_signature_valid():
raise exceptions.InvalidSignature
# Compare with known IOU
active_iou = pathfinding_service.database.get_iou(
sender=iou.sender,
claimed=False,
)
if active_iou:
if active_iou.expiration_block != iou.expiration_block:
raise exceptions.UseThisIOU(iou=active_iou)
expected_amount = active_iou.amount + pathfinding_service.service_fee
else:
claimed_iou = pathfinding_service.database.get_iou(
sender=iou.sender,
expiration_block=iou.expiration_block,
claimed=True,
)
if claimed_iou:
raise exceptions.IOUAlreadyClaimed
min_expiry = pathfinding_service.web3.eth.blockNumber + MIN_IOU_EXPIRY
if iou.expiration_block < min_expiry:
raise exceptions.IOUExpiredTooEarly(min_expiry=min_expiry)
expected_amount = pathfinding_service.service_fee
if iou.amount < expected_amount:
raise exceptions.InsufficientServicePayment(
expected_amount=expected_amount)
# Check client's deposit in UserDeposit contract
udc = pathfinding_service.user_deposit_contract
udc_balance = udc.functions.effectiveBalance(iou.sender).call()
required_deposit = round(expected_amount * UDC_SECURITY_MARGIN_FACTOR)
if udc_balance < required_deposit:
raise exceptions.DepositTooLow(required_deposit=required_deposit)
# Save latest IOU
iou.claimed = False
pathfinding_service.database.upsert_iou(iou)
def post(self, token_network_address: str) -> Tuple[dict, int]:
token_network_error = self._validate_token_network_argument(
token_network_address)
if token_network_error is not None:
return token_network_error
json = request.get_json()
if not json:
raise exceptions.ApiException('JSON payload expected')
path_req, errors = PathRequest.Schema().load(json)
if errors:
raise exceptions.InvalidRequest(**errors)
process_payment(path_req.iou, self.pathfinding_service)
token_network = self.pathfinding_service.token_networks.get(
TokenNetworkAddress(token_network_address))
# Existence is checked in _validate_token_network_argument
assert token_network, 'Requested token network cannot be found'
try:
# only optional args if not None, so we can use defaults
optional_args = {}
for arg in ['diversity_penalty', 'fee_penalty']:
value = getattr(path_req, arg)
if value is not None:
optional_args[arg] = value
paths = token_network.get_paths(
source=path_req.from_,
target=path_req.to,
value=path_req.value,
max_paths=path_req.max_paths,
**optional_args,
)
except (NetworkXNoPath, NodeNotFound):
return (
{
'errors':
'No suitable path found for transfer from {} to {}.'.
format(path_req.from_, path_req.to)
},
400,
)
return {'result': paths}, 200
def get(self,
token_network_address: TokenNetworkAddress) -> Tuple[dict, int]:
iou_request, errors = IOURequest.Schema().load(request.args)
if errors:
raise exceptions.InvalidRequest(**errors)
if not iou_request.is_signature_valid():
raise exceptions.InvalidSignature
if iou_request.timestamp < datetime.utcnow() - MAX_AGE_OF_IOU_REQUESTS:
raise exceptions.RequestOutdated
last_iou = self.pathfinding_service.database.get_iou(
sender=iou_request.sender, claimed=False)
if last_iou:
last_iou = IOU.Schema(strict=True,
exclude=["claimed"]).dump(last_iou)[0]
return {"last_iou": last_iou}, 200
return {"last_iou": None}, 404
def get(
self,
token_network_address: str # pylint: disable=unused-argument
) -> Tuple[dict, int]:
try:
iou_request = IOURequest.Schema().load(request.args)
except marshmallow.ValidationError as ex:
raise exceptions.InvalidRequest(**ex.messages)
if not iou_request.is_signature_valid():
raise exceptions.InvalidSignature
if iou_request.timestamp < datetime.utcnow() - MAX_AGE_OF_IOU_REQUESTS:
raise exceptions.RequestOutdated
last_iou = self.pathfinding_service.database.get_iou(
sender=iou_request.sender, claimed=False)
if last_iou:
last_iou = IOU.Schema(exclude=["claimed"]).dump(last_iou)
return {"last_iou": last_iou}, 200
return {"last_iou": None}, 404