amqtt/hbmqtt/mqtt/suback.py

91 wiersze
2.6 KiB
Python

# Copyright (c) 2015 Nicolas JOUANIN
#
# See the file license.txt for copying permission.
from hbmqtt.mqtt.packet import (
MQTTPacket,
MQTTFixedHeader,
SUBACK,
PacketIdVariableHeader,
MQTTPayload,
MQTTVariableHeader,
)
from hbmqtt.errors import HBMQTTException, NoDataException
from hbmqtt.adapters import ReaderAdapter
from hbmqtt.codecs import bytes_to_int, int_to_bytes, read_or_raise
class SubackPayload(MQTTPayload):
__slots__ = ("return_codes",)
RETURN_CODE_00 = 0x00
RETURN_CODE_01 = 0x01
RETURN_CODE_02 = 0x02
RETURN_CODE_80 = 0x80
def __init__(self, return_codes=None):
super().__init__()
self.return_codes = return_codes or []
def __repr__(self):
return type(self).__name__ + "(return_codes={0})".format(
repr(self.return_codes)
)
def to_bytes(
self, fixed_header: MQTTFixedHeader, variable_header: MQTTVariableHeader
):
out = b""
for return_code in self.return_codes:
out += int_to_bytes(return_code, 1)
return out
@classmethod
async def from_stream(
cls,
reader: ReaderAdapter,
fixed_header: MQTTFixedHeader,
variable_header: MQTTVariableHeader,
):
return_codes = []
bytes_to_read = fixed_header.remaining_length - variable_header.bytes_length
for i in range(0, bytes_to_read):
try:
return_code_byte = await read_or_raise(reader, 1)
return_code = bytes_to_int(return_code_byte)
return_codes.append(return_code)
except NoDataException:
break
return cls(return_codes)
class SubackPacket(MQTTPacket):
VARIABLE_HEADER = PacketIdVariableHeader
PAYLOAD = SubackPayload
def __init__(
self,
fixed: MQTTFixedHeader = None,
variable_header: PacketIdVariableHeader = None,
payload=None,
):
if fixed is None:
header = MQTTFixedHeader(SUBACK, 0x00)
else:
if fixed.packet_type is not SUBACK:
raise HBMQTTException(
"Invalid fixed packet type %s for SubackPacket init"
% fixed.packet_type
)
header = fixed
super().__init__(header)
self.variable_header = variable_header
self.payload = payload
@classmethod
def build(cls, packet_id, return_codes):
variable_header = cls.VARIABLE_HEADER(packet_id)
payload = cls.PAYLOAD(return_codes)
return cls(variable_header=variable_header, payload=payload)