mdc_logger = Logger(name=__name__)
+# With Nanomsg and NNG it was possible for a send attempt to have a "soft"
+# failure which did warrant some retries if the status of the send is RMR_ERR_RETRY.
+# Because of the way NNG worked, it sometimes required many tens of retries,
+# and a retry state happened often for even moderately "verbose" applications.
+# With SI95 there is still a possibility that a retry is necessary, but it is very rare.
RETRY_TIMES = int(os.environ.get("A1_RMR_RETRY_TIMES", 4))
A1_POLICY_REQUEST = 20010
A1_POLICY_RESPONSE = 20011
self.mrc = init_func_override()
else:
mdc_logger.debug("Waiting for rmr to initialize..")
- # rmr.RMRFL_MTCALL puts RMR into a multithreaded mode, where a receiving thread populates an
- # internal ring of messages, and receive calls read from that
+ # rmr.RMRFL_MTCALL puts RMR into a multithreaded mode, where a receiving thread
+ # populates an internal ring of messages, and receive calls read from that.
# currently the size is 2048 messages, so this is fine for the foreseeable future
self.mrc = rmr.rmr_init(b"4562", rmr.RMR_MAX_RCV_BYTES, rmr.RMRFL_MTCALL)
while rmr.rmr_ready(self.mrc) == 0:
def _assert_good_send(self, sbuf, pre_send_summary):
"""
- common helper function for _send_msg and _rts_msg
+ Extracts the send result and logs a detailed warning if the send failed.
+ Returns the message state, an integer that indicates the result.
"""
post_send_summary = rmr.message_summary(sbuf)
- if post_send_summary["message state"] == 0 and post_send_summary["message status"] == "RMR_OK":
- return True
- mdc_logger.debug("Message NOT sent!")
- mdc_logger.debug("Pre-send summary: {0}, Post-send summary: {1}".format(pre_send_summary, post_send_summary))
- return False
+ if post_send_summary[rmr.RMR_MS_MSG_STATE] != rmr.RMR_OK:
+ mdc_logger.warning("RMR send failed; pre-send summary: {0}, post-send summary: {1}".format(pre_send_summary, post_send_summary))
+ return post_send_summary[rmr.RMR_MS_MSG_STATE]
def _send_msg(self, pay, mtype, subid):
"""
- sends a msg
+ Creates and sends a message via RMR's send-message feature with the specified payload
+ using the specified message type and subscription ID.
"""
+ sbuf = rmr.rmr_alloc_msg(self.mrc, len(pay), payload=pay, gen_transaction_id=True, mtype=mtype, sub_id=subid)
+ sbuf.contents.sub_id = subid
+ pre_send_summary = rmr.message_summary(sbuf)
for _ in range(0, RETRY_TIMES):
- sbuf = rmr.rmr_alloc_msg(self.mrc, len(pay), payload=pay, gen_transaction_id=True, mtype=mtype, sub_id=subid)
- sbuf.contents.sub_id = subid
- pre_send_summary = rmr.message_summary(sbuf)
- mdc_logger.debug("Trying to send message: {}".format(pre_send_summary))
- sbuf = rmr.rmr_send_msg(self.mrc, sbuf) # send
- if self._assert_good_send(sbuf, pre_send_summary):
- rmr.rmr_free_msg(sbuf) # free
- return
+ mdc_logger.debug("_send_msg: sending: {}".format(pre_send_summary))
+ sbuf = rmr.rmr_send_msg(self.mrc, sbuf)
+ msg_state = self._assert_good_send(sbuf, pre_send_summary)
+ if msg_state != rmr.RMR_ERR_RETRY:
+ break
- mdc_logger.debug("A1 did NOT send the message successfully after {} retries!".format(RETRY_TIMES))
+ rmr.rmr_free_msg(sbuf)
+ if msg_state != rmr.RMR_OK:
+ mdc_logger.warning("_send_msg: failed after {} retries".format(RETRY_TIMES))
def _rts_msg(self, pay, sbuf_rts, mtype):
"""
- sends a message using rts
- we do not call free here because we may rts many times; it is called after the rts loop
+ Sends a message via RMR's return-to-sender feature.
+ This neither allocates nor frees a message buffer because we may rts many times.
+ Returns the message buffer from the RTS function, which may reallocate it.
"""
+ pre_send_summary = rmr.message_summary(sbuf_rts)
for _ in range(0, RETRY_TIMES):
- pre_send_summary = rmr.message_summary(sbuf_rts)
+ mdc_logger.debug("_rts_msg: sending: {}".format(pre_send_summary))
sbuf_rts = rmr.rmr_rts_msg(self.mrc, sbuf_rts, payload=pay, mtype=mtype)
- if self._assert_good_send(sbuf_rts, pre_send_summary):
+ msg_state = self._assert_good_send(sbuf_rts, pre_send_summary)
+ if msg_state != rmr.RMR_ERR_RETRY:
break
+
+ if msg_state != rmr.RMR_OK:
+ mdc_logger.warning("_rts_msg: failed after {} retries".format(RETRY_TIMES))
return sbuf_rts # in some cases rts may return a new sbuf
def _handle_sends(self):
for (msg, sbuf) in self.rcv_func():
# TODO: in the future we may also have to catch SDL errors
try:
- mtype = msg["message type"]
+ mtype = msg[rmr.RMR_MS_MSG_TYPE]
except (KeyError, TypeError, json.decoder.JSONDecodeError):
- mdc_logger.debug("Dropping malformed policy ack/query message: {0}".format(msg))
+ mdc_logger.warning("Dropping malformed message: {0}".format(msg))
if mtype == A1_POLICY_RESPONSE:
try:
# got a policy response, update status
- pay = json.loads(msg["payload"])
+ pay = json.loads(msg[rmr.RMR_MS_PAYLOAD])
data.set_policy_instance_status(
pay["policy_type_id"], pay["policy_instance_id"], pay["handler_id"], pay["status"]
)
mdc_logger.debug("Successfully received status update: {0}".format(pay))
except (PolicyTypeNotFound, PolicyInstanceNotFound):
- mdc_logger.debug("Received a response for a non-existent instance")
+ mdc_logger.warning("Received a response for a non-existent type/instance: {0}".format(msg))
except (KeyError, TypeError, json.decoder.JSONDecodeError):
- mdc_logger.debug("Dropping malformed policy ack message: {0}".format(msg))
+ mdc_logger.warning("Dropping malformed policy response: {0}".format(msg))
elif mtype == A1_POLICY_QUERY:
try:
# got a query, do a lookup and send out all instances
- pti = json.loads(msg["payload"])["policy_type_id"]
+ pti = json.loads(msg[rmr.RMR_MS_PAYLOAD])["policy_type_id"]
instance_list = data.get_instance_list(pti) # will raise if a bad type
- mdc_logger.debug("Received a query for a good type: {0}".format(msg))
+ mdc_logger.debug("Received a query for a known policy type: {0}".format(msg))
for pii in instance_list:
instance = data.get_policy_instance(pti, pii)
payload = json.dumps(messages.a1_to_handler("CREATE", pti, pii, instance)).encode("utf-8")
sbuf = self._rts_msg(payload, sbuf, A1_POLICY_REQUEST)
except (PolicyTypeNotFound):
- mdc_logger.debug("Received a query for a non-existent type: {0}".format(msg))
+ mdc_logger.warning("Received a policy query for a non-existent type: {0}".format(msg))
except (KeyError, TypeError, json.decoder.JSONDecodeError):
- mdc_logger.debug("Dropping malformed policy query message: {0}".format(msg))
+ mdc_logger.warning("Dropping malformed policy query: {0}".format(msg))
else:
- mdc_logger.debug("Received message type {0} but A1 does not handle this".format(mtype))
+ mdc_logger.warning("Received message type {0} but A1 does not handle this".format(mtype))
# we must free each sbuf
rmr.rmr_free_msg(sbuf)
Code Review / ric-plt / a1.git / blobdiff