def is_free_call_available(self, service_client):
try:
org_id, service_id, group_id, daemon_endpoint = service_client.get_service_details(
)
email, token_for_free_call, token_expiry_date_block = service_client.get_free_call_config(
)
if not token_for_free_call:
return False
signature, current_block_number = self.generate_signature(
service_client)
with add_to_path(str(RESOURCES_PATH.joinpath("proto"))):
state_service_pb2 = importlib.import_module(
"state_service_pb2")
with add_to_path(str(RESOURCES_PATH.joinpath("proto"))):
state_service_pb2_grpc = importlib.import_module(
"state_service_pb2_grpc")
request = state_service_pb2.FreeCallStateRequest()
request.user_id = email
request.token_for_free_call = token_for_free_call
request.token_expiry_date_block = token_expiry_date_block
request.signature = signature
request.current_block = current_block_number
endpoint_object = urlparse(daemon_endpoint)
if endpoint_object.port is not None:
channel_endpoint = endpoint_object.hostname + ":" + str(
endpoint_object.port)
else:
channel_endpoint = endpoint_object.hostname
if endpoint_object.scheme == "http":
channel = grpc.insecure_channel(channel_endpoint)
elif endpoint_object.scheme == "https":
channel = grpc.secure_channel(
channel_endpoint,
grpc.ssl_channel_credentials(
root_certificates=root_certificate))
else:
raise ValueError(
'Unsupported scheme in service metadata ("{}")'.format(
endpoint_object.scheme))
stub = state_service_pb2_grpc.FreeCallStateServiceStub(channel)
response = stub.GetFreeCallsAvailable(request)
if response.free_calls_available > 0:
return True
return False
except Exception as e:
return False
def _generate_payment_channel_state_service_client(self):
grpc_channel = self.__base_grpc_channel
with add_to_path(str(RESOURCES_PATH.joinpath("proto"))):
state_service_pb2_grpc = importlib.import_module(
"state_service_pb2_grpc")
return state_service_pb2_grpc.PaymentChannelStateServiceStub(
grpc_channel)
def __get_token_for_amount(self, service_client, channel, amount):
nonce = channel.state["nonce"]
stub = self.__get_stub_for_get_token(service_client)
with add_to_path(str(RESOURCES_PATH.joinpath("proto"))):
token_service_pb2 = importlib.import_module("token_service_pb2")
current_block_number = service_client.sdk_web3.eth.getBlock("latest").number
message = web3.Web3.soliditySha3(
["string", "address", "uint256", "uint256", "uint256"],
["__MPE_claim_message", service_client.mpe_address, channel.channel_id, nonce, amount]
)
mpe_signature = service_client.generate_signature(message)
message = web3.Web3.soliditySha3(
["bytes", "uint256"],
[mpe_signature, current_block_number]
)
sign_mpe_signature = service_client.generate_signature(message)
request = token_service_pb2.TokenRequest(
channel_id=channel.channel_id, current_nonce=nonce, signed_amount=amount,
signature=bytes(sign_mpe_signature), claim_signature=bytes(mpe_signature),
current_block=current_block_number)
token_reply = stub.GetToken(request)
return token_reply
def __get_stub_for_get_token(self, service_client):
grpc_channel = service_client.get_grpc_base_channel()
with add_to_path(str(RESOURCES_PATH.joinpath("proto"))):
token_service_pb2_grpc = importlib.import_module("token_service_pb2_grpc")
return token_service_pb2_grpc.TokenServiceStub(grpc_channel)