def send_message(self, message, tries=0, no_wait=False):
"""
sends input with write
returns output with read.
if skip_read is True, it only returns true, you have to read
yourself.
"""
if message:
self.write(message.as_bin())
# time.sleep(0.1)
acknowledge = self.connection.read(1)
self.slog(acknowledge, True)
# if nak, we retry, if ack, we read, if other, we raise.
if acknowledge == ensure_bytes(chr(ACK)):
# everything alright.
if not no_wait:
return self.receive()
return True
elif acknowledge == ensure_bytes(chr(NAK)):
# not everything allright.
#if tries < 3:
# return self.send_message(message, tries + 1, no_answer)
#else:
raise common.TransportLayerException("Could not send message")
elif not acknowledge:
# this happens quite a lot with the ingenico devices.
# possibly a workaround would be nice.
raise common.TransportTimeoutException(
"No Answer, Possible Timeout")
else:
raise common.TransportLayerException(
"Unknown Acknowledgment Byte %s" % conv.bs2hl(acknowledge))
def send_message(self, message, tries=0, no_wait=False):
"""
sends input with write
returns output with read.
if skip_read is True, it only returns true, you have to read
yourself.
"""
if message:
self.write(message.as_bin())
acknowledge = b''
ts_start = time()
while not acknowledge:
acknowledge = self.connection.read(1)
# With ingenico devices, acknowledge is often empty.
# Just retrying seems to help.
if time() - ts_start > 1:
break
self.slog(acknowledge, True)
# if nak, we retry, if ack, we read, if other, we raise.
if acknowledge == ensure_bytes(chr(ACK)):
# everything alright.
if no_wait:
return True
return self.receive()
elif acknowledge == ensure_bytes(chr(NAK)):
# not everything allright.
# if tries < 3:
# return self.send_message(message, tries + 1, no_answer)
# else:
raise TransportLayerException('Could not send message')
elif not acknowledge:
raise TransportTimeoutException('No Answer, Possible Timeout')
else:
raise TransportLayerException(
'Unknown Acknowledgment Byte %s' % bs2hl(acknowledge))
def write_nak(self):
try:
self.slog([NAK])
finally:
self.connection.write(ensure_bytes(chr(NAK)))
def write_ack(self):
# writes an ack.
try:
self.slog([ACK])
finally:
self.connection.write(ensure_bytes(chr(ACK)))
def write(self, something=None):
if something:
try:
self.slog(conv.bs2hl(something))
finally:
self.connection.write(ensure_bytes(something)) # !?