X-Git-Url: https://gerrit.o-ran-sc.org/r/gitweb?a=blobdiff_plain;f=a1%2Fa1rmr.py;h=ae2bf00800b0df804567da0da5dcef085b4805d3;hb=6fceb807d55359d5c50a96d455fc8f47111f2733;hp=d6114bf38e232112a91dfddb445eae1672e338d2;hpb=6b69910923309e05820706dc025e1441463906c9;p=ric-plt%2Fa1.git diff --git a/a1/a1rmr.py b/a1/a1rmr.py index d6114bf..ae2bf00 100644 --- a/a1/a1rmr.py +++ b/a1/a1rmr.py @@ -1,3 +1,6 @@ +""" +a1s rmr functionality +""" # ================================================================================== # Copyright (c) 2019 Nokia # Copyright (c) 2018-2019 AT&T Intellectual Property. @@ -18,89 +21,127 @@ import os import queue import time import json +from threading import Thread from rmr import rmr, helpers -from a1 import get_module_logger +from mdclogpy import Logger from a1 import data from a1.exceptions import PolicyTypeNotFound, PolicyInstanceNotFound -logger = get_module_logger(__name__) +mdc_logger = Logger(name=__name__) -RETRY_TIMES = int(os.environ.get("RMR_RETRY_TIMES", 4)) +RETRY_TIMES = int(os.environ.get("A1_RMR_RETRY_TIMES", 4)) -_SEND_QUEUE = queue.Queue() # thread safe queue https://docs.python.org/3/library/queue.html +A1_POLICY_REQUEST = 20010 +A1_POLICY_RESPONSE = 20011 +A1_POLICY_QUERY = 20012 -def _init_rmr(): + +# Note; yes, globals are bad, but this is a private (to this module) global +# No other module can import/access this (well, python doesn't enforce this, but all linters will complain) +__RMR_LOOP__ = None + + +class _RmrLoop: """ - init an rmr context - This gets monkeypatched out for unit testing + class represents an rmr loop that constantly reads from rmr and performs operations based on waiting messages + this launches a thread, it should probably only be called once; the public facing method to access these ensures this """ - # 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 - mrc = rmr.rmr_init(b"4562", rmr.RMR_MAX_RCV_BYTES, rmr.RMRFL_MTCALL) - while rmr.rmr_ready(mrc) == 0: - time.sleep(0.5) + def __init__(self, init_func_override=None, rcv_func_override=None): + self.keep_going = True + self.rcv_func = None + self.last_ran = time.time() + self.work_queue = queue.Queue() # thread safe queue https://docs.python.org/3/library/queue.html + + # intialize rmr context + if init_func_override: + 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 + # 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: + time.sleep(0.5) + + # set the receive function + # TODO: when policy query is implemented, add A1_POLICY_QUERY + self.rcv_func = ( + rcv_func_override if rcv_func_override else lambda: helpers.rmr_rcvall_msgs(self.mrc, [A1_POLICY_RESPONSE]) + ) + + # start the work loop + self.thread = Thread(target=self.loop) + self.thread.start() + + def loop(self): + """ + This loop runs forever, and has 3 jobs: + - send out any messages that have to go out (create instance, delete instance) + - read a1s mailbox and update the status of all instances based on acks from downstream policy handlers + - clean up the database (eg delete the instance) under certain conditions based on those statuses (NOT DONE YET) + """ + # loop forever + mdc_logger.debug("Work loop starting") + while self.keep_going: + + # send out all messages waiting for us + while not self.work_queue.empty(): + work_item = self.work_queue.get(block=False, timeout=None) + + pay = work_item["payload"].encode("utf-8") + for _ in range(0, RETRY_TIMES): + # Waiting on an rmr bugfix regarding the over-allocation: https://rancodev.atlassian.net/browse/RICPLT-2490 + sbuf = rmr.rmr_alloc_msg(self.mrc, 4096, pay, True, A1_POLICY_REQUEST) + # TODO: after next rmr is released, this can be done in the alloc call. but that's not avail in pypi yet + sbuf.contents.sub_id = work_item["ptid"] + pre_send_summary = rmr.message_summary(sbuf) + sbuf = rmr.rmr_send_msg(self.mrc, sbuf) # send + post_send_summary = rmr.message_summary(sbuf) + mdc_logger.debug( + "Pre-send summary: {0}, Post-send summary: {1}".format(pre_send_summary, post_send_summary) + ) + rmr.rmr_free_msg(sbuf) # free + if post_send_summary["message state"] == 0 and post_send_summary["message status"] == "RMR_OK": + mdc_logger.debug("Message sent successfully!") + break + + # read our mailbox and update statuses + for msg in self.rcv_func(): + try: + pay = json.loads(msg["payload"]) + pti = pay["policy_type_id"] + pii = pay["policy_instance_id"] + data.set_policy_instance_status(pti, pii, pay["handler_id"], pay["status"]) + except (PolicyTypeNotFound, PolicyInstanceNotFound, KeyError, TypeError, json.decoder.JSONDecodeError): + # TODO: in the future we may also have to catch SDL errors + mdc_logger.debug("Dropping malformed or non applicable message: {0}".format(msg)) + + # TODO: what's a reasonable sleep time? we don't want to hammer redis too much, and a1 isn't a real time component + self.last_ran = time.time() + time.sleep(1) + - return mrc +# Public -def _send(mrc, payload, message_type=0): - """ - Sends a message up to RETRY_TIMES - If the message is sent successfully, it returns the transactionid - Does nothing otherwise - """ - # TODO: investigate moving this below and allocating the space based on the payload size - sbuf = rmr.rmr_alloc_msg(mrc, 4096) - payload = payload if isinstance(payload, bytes) else payload.encode("utf-8") - - # retry RETRY_TIMES to send the message - for _ in range(0, RETRY_TIMES): - # setup the send message - rmr.set_payload_and_length(payload, sbuf) - rmr.generate_and_set_transaction_id(sbuf) - sbuf.contents.state = 0 - sbuf.contents.mtype = message_type - pre_send_summary = rmr.message_summary(sbuf) - logger.debug("Pre message send summary: %s", pre_send_summary) - transaction_id = pre_send_summary["transaction id"] # save the transactionid because we need it later - - # send - sbuf = rmr.rmr_send_msg(mrc, sbuf) - post_send_summary = rmr.message_summary(sbuf) - logger.debug("Post message send summary: %s", rmr.message_summary(sbuf)) - - # check success or failure - if post_send_summary["message state"] == 0 and post_send_summary["message status"] == "RMR_OK": - # we are good - logger.debug("Message sent successfully!") - rmr.rmr_free_msg(sbuf) - return transaction_id - - # we failed all RETRY_TIMES - logger.debug("Send failed all %s times, stopping", RETRY_TIMES) - rmr.rmr_free_msg(sbuf) - return None - - -def _update_all_statuses(mrc): +def start_rmr_thread(init_func_override=None, rcv_func_override=None): """ - get all waiting messages, and try to parse them as status updates - (currently, those are the only messages a1 should get, this may have to be revisited later) + Start a1s rmr thread """ - for msg in helpers.rmr_rcvall_msgs(mrc, [21024]): - try: - pay = json.loads(msg["payload"]) - data.set_status(pay["policy_type_id"], pay["policy_instance_id"], pay["handler_id"], pay["status"]) - except (PolicyTypeNotFound, PolicyInstanceNotFound, KeyError): - logger.debug("Dropping malformed or non applicable message") - logger.debug(msg) + global __RMR_LOOP__ + if __RMR_LOOP__ is None: + __RMR_LOOP__ = _RmrLoop(init_func_override, rcv_func_override) -# Public +def stop_rmr_thread(): + """ + stops the rmr thread + """ + __RMR_LOOP__.keep_going = False def queue_work(item): @@ -108,63 +149,18 @@ def queue_work(item): push an item into the work queue currently the only type of work is to send out messages """ - _SEND_QUEUE.put(item) + __RMR_LOOP__.work_queue.put(item) -class RmrLoop: +def healthcheck_rmr_thread(seconds=30): """ - class represents an rmr loop meant to be called as a longstanding separate thread + returns a boolean representing whether the rmr loop is healthy, by checking two attributes: + 1. is it running?, + 2. is it stuck in a long (> seconds) loop? """ + return __RMR_LOOP__.thread.is_alive() and ((time.time() - __RMR_LOOP__.last_ran) < seconds) - def __init__(self, real_init=True): - self._rmr_is_ready = False - self._keep_going = True - self._real_init = real_init # useful for unit testing to turn off initialization - - def rmr_is_ready(self): - """returns whether rmr has been initialized""" - return self._rmr_is_ready - - def stop(self): - """sets a flag for the loop to end""" - self._keep_going = False - - def loop(self): - """ - This loop runs in an a1 thread forever, and has 3 jobs: - - send out any messages that have to go out (create instance, delete instance) - - read a1s mailbox and update the status of all instances based on acks from downstream policy handlers - - clean up the database (eg delete the instance) under certain conditions based on those statuses (NOT DONE YET) - """ - - # get a context - mrc = None - logger.debug("Waiting for rmr to initialize...") - if self._real_init: - mrc = _init_rmr() - self._rmr_is_ready = True - logger.debug("Rmr is ready") - - # loop forever - logger.debug("Work loop starting") - while self._keep_going: - """ - We never raise an exception here. Log and keep moving - Bugs will eventually be caught be examining logs. - """ - try: - # First, send out all messages waiting for us - while not _SEND_QUEUE.empty(): - work_item = _SEND_QUEUE.get(block=False, timeout=None) - _send(mrc, payload=work_item["payload"], message_type=work_item["msg type"]) - - # Next, update all statuses waiting in a1s mailbox - _update_all_statuses(mrc) - - # TODO: next body of work is to try to clean up the database for any updated statuses - - except Exception as e: - logger.debug("Polling thread encountered an unexpected exception, but it will continue:") - logger.exception(e) - time.sleep(1) +def replace_rcv_func(rcv_func): + """purely for the ease of unit testing to test different rcv scenarios""" + __RMR_LOOP__.rcv_func = rcv_func