class TestDLTClient(unittest.TestCase):
def setUp(self):
# - patch port so that connect fails even if dlt-daemon is running
self.client = DLTClient(servIP='127.0.0.1', port=424242)
def test_connect_with_timeout_failed(self):
# - timeout error
self.assertFalse(self.client.connect(timeout=2))
# - dlt_receiver_init error
with patch('socket.create_connection', return_value=Mock(fileno=Mock(return_value=2000000))), \
patch('dlt.dlt.dltlib.dlt_receiver_init', return_value=DLT_RETURN_ERROR):
self.assertFalse(self.client.connect(timeout=2))
def test_connect_with_timeout_success(self):
with patch('socket.create_connection', return_value=Mock(fileno=Mock(return_value=2000000))), \
patch('dlt.dlt.dltlib.dlt_receiver_init', return_value=DLT_RETURN_OK):
self.assertTrue(self.client.connect(timeout=2))
class DLTMessageHandler(Process):
"""Process receiving the DLT messages and handing them to DLTContextHandler
This process instance is responsible for collecting messages from
the DLT daemon, tagging them with the correct queue id and placing
them on the messages queue.
"""
def __init__(self, filter_queue, message_queue, mp_stop_event, client_cfg):
self.filter_queue = filter_queue
self.message_queue = message_queue
self.mp_stop_flag = mp_stop_event
super(DLTMessageHandler, self).__init__()
# - dict mapping filters to queue ids
self.context_map = defaultdict(list)
self._ip_address = client_cfg["ip_address"]
self._filename = client_cfg.get("filename")
self.verbose = client_cfg.get("verbose", 0)
self.timeout = client_cfg.get("timeout", DLT_CLIENT_TIMEOUT)
self._client = None
self.tracefile = None
def _client_connect(self):
"""Create a new DLTClient
:param int timeout: Time in seconds to wait for connection.
:returns: True if connected, False otherwise
:rtype: bool
"""
logger.debug("Creating DLTClient (ip_address='%s', logfile='%s')",
self._ip_address, self._filename)
self._client = DLTClient(servIP=self._ip_address, verbose=self.verbose)
connected = self._client.connect(self.timeout)
if connected:
logger.info("DLTClient connected to %s", self._client.servIP)
return connected
def _process_filter_queue(self):
"""Check if filters have been added or need to be removed"""
while not self.filter_queue.empty():
queue_id, filters, add = self.filter_queue.get_nowait()
if add:
for apid_ctid in filters:
self.context_map[apid_ctid].append(queue_id)
else:
try:
for apid_ctid in filters:
self.context_map[apid_ctid].remove(queue_id)
if not self.context_map[apid_ctid]:
del (self.context_map[apid_ctid])
except (KeyError, ValueError):
# - queue_id already removed or not inserted
pass
def handle(self, message):
"""Function to be called for every message received
:param DLTMessage message: received new DLTMessage instance
:returns: True if the loop should continue, False to stop the loop and exit
:rtype: bool
"""
self._process_filter_queue()
if message is not None and not (message.apid == ""
and message.ctid == ""):
for filters, queue_ids in self.context_map.items():
if filters in [(message.apid, message.ctid), (None, None),
(message.apid, None), (None, message.ctid)]:
for queue_id in queue_ids:
if self.message_queue.full():
logger.error(
"message_queue is full ! put() on this queue will block"
)
self.message_queue.put((queue_id, message))
return not self.mp_stop_flag.is_set()
def run(self):
"""DLTMessageHandler worker method"""
if self._filename is not None:
logger.info("Opening the DLT trace file '%s'", self._filename)
self.tracefile = open(self._filename, mode="ab", buffering=False)
while not self.mp_stop_flag.is_set():
exception_occured = False
if not self._client_connect():
# keep trying to reconnect, until we either successfully
# connect or the stop_flag is set
continue
try:
res = py_dlt_client_main_loop(self._client,
verbose=0,
callback=self.handle,
dumpfile=self.tracefile)
if res is False and not self.mp_stop_flag.is_set(
): # main loop returned False
logger.error("DLT connection lost. Restarting DLT client")
exception_occured = True
except KeyboardInterrupt:
exception_occured = True
logger.debug("main loop manually interrupted")
break
except socket.timeout as exc:
exception_occured = True
logger.error("socket timeout error")
logger.debug(exc)
except Exception: # pylint: disable=broad-except
exception_occured = True
logger.exception("Exception during the DLT message receive")
finally:
if exception_occured:
logger.debug("Closing open socket connections.")
self._client.disconnect()
self.message_queue.close()
logger.info("DLTMessageHandler worker execution complete")