def subscribe(self, client_id=b'1001', destination=b'example', filter=b'.*\\..*'):
self.client_id = client_id
self.destination = destination
self.rollback(0)
sub = CanalProtocol_pb2.Sub()
sub.destination = destination
sub.client_id = client_id
sub.filter = filter
packet = CanalProtocol_pb2.Packet()
packet.type = CanalProtocol_pb2.PacketType.SUBSCRIPTION
packet.body = sub.SerializeToString()
self.connector.write_with_header(packet.SerializeToString())
data = self.connector.read_next_packet()
packet = CanalProtocol_pb2.Packet()
packet.MergeFromString(data)
if packet.type != CanalProtocol_pb2.PacketType.ACK:
raise Exception('Subscribe error.')
ack = CanalProtocol_pb2.Ack()
ack.MergeFromString(packet.body)
if ack.error_code > 0:
raise Exception(
'Failed to subscribe. error code:%s, error message:%s' % (ack.error_code, ack.error_message))
print('Subscribe succed')
def rollback(self, batch_id):
cb = CanalProtocol_pb2.ClientRollback()
cb.batch_id = batch_id
cb.client_id = self.client_id
cb.destination = self.destination
packet = CanalProtocol_pb2.Packet()
packet.type = CanalProtocol_pb2.PacketType.CLIENTROLLBACK
packet.body = cb.SerializeToString()
self.connector.write_with_header(packet.SerializeToString())
def ack(self, message_id):
if message_id:
clientack = CanalProtocol_pb2.ClientAck()
clientack.destination = self.destination
clientack.client_id = self.client_id
clientack.batch_id = message_id
packet = CanalProtocol_pb2.Packet()
packet.type = CanalProtocol_pb2.PacketType.CLIENTACK
packet.body = clientack.SerializeToString()
self.connector.write_with_header(packet.SerializeToString())
def connect(self, host='127.0.0.1', port=11111):
self.connector.connect(host, port)
data = self.connector.read_next_packet()
packet = CanalProtocol_pb2.Packet()
packet.MergeFromString(data)
if packet.type != CanalProtocol_pb2.PacketType.HANDSHAKE:
raise Exception('connect error')
print('connected to %s:%s' % (host, port))
def get_without_ack(self, batch_size=10, timeout=-1, unit=-1):
get = CanalProtocol_pb2.Get()
get.client_id = self.client_id
get.destination = self.destination
get.auto_ack = False
get.fetch_size = batch_size
get.timeout = timeout
get.unit = unit
packet = CanalProtocol_pb2.Packet()
packet.type = CanalProtocol_pb2.PacketType.GET
packet.body = get.SerializeToString()
self.connector.write_with_header(packet.SerializeToString())
data = self.connector.read_next_packet()
packet = CanalProtocol_pb2.Packet()
packet.MergeFromString(data)
message = dict(id=0, entries=[])
if packet.type == CanalProtocol_pb2.PacketType.MESSAGES:
messages = CanalProtocol_pb2.Messages()
messages.MergeFromString(packet.body)
if messages.batch_id > 0:
message['id'] = messages.batch_id
for item in messages.messages:
entry = EntryProtocol_pb2.Entry()
entry.MergeFromString(item)
message['entries'].append(entry)
elif packet.type == CanalProtocol_pb2.PacketType.ACK:
ack = CanalProtocol_pb2.PacketType.Ack()
ack.MergeFromString(packet.body)
if ack.error_code > 0:
raise Exception(
'get data error. error code:%s, error message:%s' %
(ack.error_code, ack.error_message))
else:
raise Exception('unexpected packet type:%s' % (packet.type))
return message
def check_valid(self, username=b'', password=b''):
client_auth = CanalProtocol_pb2.ClientAuth()
client_auth.username = username
client_auth.password = password
packet = CanalProtocol_pb2.Packet()
packet.type = CanalProtocol_pb2.PacketType.CLIENTAUTHENTICATION
packet.body = client_auth.SerializeToString()
self.connector.write_with_header(packet.SerializeToString())
data = self.connector.read_next_packet()
packet = CanalProtocol_pb2.Packet()
packet.MergeFromString(data)
if packet.type != CanalProtocol_pb2.PacketType.ACK:
raise Exception('Auth error')
ack = CanalProtocol_pb2.Ack()
ack.MergeFromString(packet.body)
if ack.error_code > 0:
raise Exception('something goes wrong when doing authentication. error code:%s, error message:%s' % (
ack.error_code, ack.error_message))
print('Auth succed')