pyztk/zk/base.py
2016-05-23 13:55:09 +07:00

141 lines
4.3 KiB
Python

# -*- coding: utf-8 -*-
from struct import pack, unpack
from socket import socket, AF_INET, SOCK_DGRAM
from zk import const
class ZK(object):
__data_recv = None
def __init__(self, ip, port=4370, timeout=5):
self.address = (ip, port)
self.__address = (ip, port)
self.__sock = socket(AF_INET, SOCK_DGRAM)
self.__sock.settimeout(timeout)
def __create_header(self, command, chksum=0, session_id=0, reply_id=65534, command_string=''):
'''
Puts a the parts that make up a packet together and packs them into a byte string
'''
buf = pack('HHHH', command, chksum, session_id, reply_id) + command_string
buf = unpack('8B'+'%sB' % len(command_string), buf)
chksum = unpack('H', self.__create_checksum(buf))[0]
reply_id += 1
if reply_id >= const.USHRT_MAX:
reply_id -= const.USHRT_MAX
buf = pack('HHHH', command, chksum, session_id, reply_id)
return buf + command_string
def __create_checksum(self, p):
'''
Calculates the chksum of the packet to be sent to the time clock
Copied from zkemsdk.c
'''
l = len(p)
chksum = 0
while l > 1:
chksum += unpack('H', pack('BB', p[0], p[1]))[0]
p = p[2:]
if chksum > const.USHRT_MAX:
chksum -= const.USHRT_MAX
l -= 2
if l:
chksum = chksum + p[-1]
while chksum > const.USHRT_MAX:
chksum -= const.USHRT_MAX
chksum = ~chksum
while chksum < 0:
chksum += const.USHRT_MAX
return pack('H', chksum)
@property
def __response(self):
'''
Checks a returned packet to see if it returned `CMD_ACK_OK` indicating success
'''
return unpack('HHHH', self.__data_recv[:8])[0]
@property
def __sesion_id(self):
return unpack('HHHH', self.__data_recv[:8])[2]
@property
def __reply_id(self):
return unpack('HHHH', self.__data_recv[:8])[3]
def connect(self):
'''
connect to device
'''
command = const.CMD_CONNECT
try:
buf = self.__create_header(command=command)
self.__sock.sendto(buf, self.address)
self.__data_recv, addr = self.__sock.recvfrom(1024)
if self.__response == const.CMD_ACK_OK:
return (True, self.__response)
else:
return (False, self.__response)
except Exception, e:
return (False, e)
def disconnect(self):
'''
diconnect from connected device
'''
command = const.CMD_EXIT
try:
buf = self.__create_header(command=command, session_id=self.__sesion_id, reply_id=self.__reply_id)
self.__sock.sendto(buf, self.__address)
self.__data_recv, addr = self.__sock.recvfrom(1024)
if self.__response == const.CMD_ACK_OK:
return (True, self.__response)
else:
return (False, self.__response)
except Exception, e:
return (False, e)
def restart(self):
'''
shutdown device
'''
command = const.CMD_RESTART
try:
buf = self.__create_header(command=command, session_id=self.__sesion_id, reply_id=self.__reply_id)
self.__sock.sendto(buf, self.__address)
self.__data_recv, addr = self.__sock.recvfrom(1024)
if self.__response == const.CMD_ACK_OK:
return (True, self.__response)
else:
return (False, self.__response)
except Exception, e:
return (False, e)
def power_off(self):
'''
shutdown device
'''
command = const.CMD_POWEROFF
try:
buf = self.__create_header(command=command, session_id=self.__sesion_id, reply_id=self.__reply_id)
self.__sock.sendto(buf, self.__address)
self.__data_recv, addr = self.__sock.recvfrom(1024)
if self.__response == const.CMD_ACK_OK:
return (True, self.__response)
else:
return (False, self.__response)
except Exception, e:
return (False, e)