X-Git-Url: https://gerrit.o-ran-sc.org/r/gitweb?a=blobdiff_plain;f=a1%2Fcontroller.py;h=42102668945d8ae5e4ac973ea5525be40647b3af;hb=refs%2Fchanges%2F10%2F2310%2F2;hp=e6e093fe1c91375f55b0c58aabd6eb14d3562744;hpb=fdf050451414e1a816e343bcd56f33186a742e49;p=ric-plt%2Fa1.git diff --git a/a1/controller.py b/a1/controller.py index e6e093f..4210266 100644 --- a/a1/controller.py +++ b/a1/controller.py @@ -1,6 +1,9 @@ +""" +Main a1 controller +""" # ================================================================================== -# Copyright (c) 2019 Nokia -# Copyright (c) 2018-2019 AT&T Intellectual Property. +# Copyright (c) 2019-2020 Nokia +# Copyright (c) 2018-2020 AT&T Intellectual Property. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. @@ -14,148 +17,168 @@ # See the License for the specific language governing permissions and # limitations under the License. # ================================================================================== -from flask import Response -import connexion -import json +from jsonschema import validate from jsonschema.exceptions import ValidationError -from a1 import get_module_logger -from a1 import a1rmr, exceptions, utils +import connexion +from mdclogpy import Logger +from ricsdl.exceptions import RejectedByBackend, NotConnected, BackendError +from a1 import a1rmr, exceptions, data + + +mdc_logger = Logger(name=__name__) + + +def _try_func_return(func): + """ + generic caller that returns the apporp http response if exceptions are raised + """ + try: + return func() + except (ValidationError, exceptions.PolicyTypeAlreadyExists, exceptions.CantDeleteNonEmptyType): + return "", 400 + except (exceptions.PolicyTypeNotFound, exceptions.PolicyInstanceNotFound): + return "", 404 + except (RejectedByBackend, NotConnected, BackendError): + """ + These are SDL errors. At the time of development here, we do not have a good understanding which of these errors are "try again later it may work" + and which are "never going to work". There is some discussion that RejectedByBackend is in the latter category, suggesting it should map to 400, + but until we understand the root cause of these errors, it's confusing to clients to give them a 400 (a "your fault" code) because they won't know how to fix + For now, we log, and 503, and investigate the logs later to improve the handling/reporting. + """ + # mdc_logger.exception(exc) # waiting for https://jira.o-ran-sc.org/browse/RIC-39 + return "", 503 + + # let other types of unexpected exceptions blow up and log + + +# Healthcheck -logger = get_module_logger(__name__) +def get_healthcheck(): + """ + Handles healthcheck GET + Currently, this checks: + 1. whether the a1 webserver is up (if it isn't, this won't even be called, so even entering this function confirms it is) + 2. checks whether the rmr thread is running and has completed a loop recently + 3. checks that our SDL connection is healthy + """ + if not a1rmr.healthcheck_rmr_thread(): + return "rmr thread is unhealthy", 500 + if not data.SDL.healthcheck(): + return "sdl connection is unhealthy", 500 + return "", 200 -def _get_policy_definition(policyname): - # Currently we read the manifest on each call, which would seem to allow updating A1 in place. Revisit this? - manifest = utils.get_ric_manifest() - for m in manifest["controls"]: - if m["name"] == policyname: - return m - raise exceptions.PolicyNotFound() +# Policy types -def _get_needed_policy_info(policyname): +def get_all_policy_types(): """ - Get the needed info for a policy + Handles GET /a1-p/policytypes """ - m = _get_policy_definition(policyname) - return ( - utils.rmr_string_to_int(m["message_receives_rmr_type"]), - m["message_receives_payload_schema"] if "message_receives_payload_schema" in m else None, - utils.rmr_string_to_int(m["message_sends_rmr_type"]), - ) + return _try_func_return(data.get_type_list) -def _get_needed_policy_fetch_info(policyname): +def create_policy_type(policy_type_id): """ - Get the needed info for fetching a policy state + Handles PUT /a1-p/policytypes/policy_type_id """ - m = _get_policy_definition(policyname) - req_k = "control_state_request_rmr_type" - ack_k = "control_state_request_reply_rmr_type" - return ( - utils.rmr_string_to_int(m[req_k]) if req_k in m else None, - utils.rmr_string_to_int(m[ack_k]) if ack_k in m else None, - ) + def put_type_handler(): + data.store_policy_type(policy_type_id, body) + return "", 201 -def _try_func_return(func): + body = connexion.request.json + return _try_func_return(put_type_handler) + + +def get_policy_type(policy_type_id): """ - generic caller that returns the apporp http response if exceptions are raised + Handles GET /a1-p/policytypes/policy_type_id """ - try: - return func() - except ValidationError as exc: - logger.exception(exc) - return "", 400 - except exceptions.PolicyNotFound as exc: - logger.exception(exc) - return "", 404 - except exceptions.MissingManifest as exc: - logger.exception(exc) - return "A1 was unable to find the required RIC manifest. report this!", 500 - except exceptions.MissingRmrString as exc: - logger.exception(exc) - return "A1 does not have a mapping for the desired rmr string. report this!", 500 - except exceptions.MessageSendFailure as exc: - logger.exception(exc) - return "A1 was unable to send a needed message to a downstream subscriber", 504 - except exceptions.ExpectedAckNotReceived as exc: - logger.exception(exc) - return "A1 was expecting an ACK back but it didn't receive one or didn't recieve the expected ACK", 504 - except BaseException as exc: - # catch all, should never happen... - logger.exception(exc) - return Response(status=500) - - -def _put_handler(policyname, data): - """ - Handles policy put - """ - - mtype_send, schema, mtype_return = _get_needed_policy_info(policyname) - - # validate the PUT against the schema, or if there is no shema, make sure the pUT is empty - if schema: - utils.validate_json(data, schema) - elif data != {}: - return "BODY SUPPLIED BUT POLICY HAS NO EXPECTED BODY", 400 - - # send rmr, wait for ACK - return_payload = a1rmr.send_ack_retry(json.dumps(data), message_type=mtype_send, expected_ack_message_type=mtype_return) - - # right now it is assumed that xapps respond with JSON payloads - # it is further assumed that they include a field "status" and that the value "SUCCESS" indicates a good policy change - try: - rpj = json.loads(return_payload) - return (rpj, 200) if rpj["status"] == "SUCCESS" else ({"reason": "BAD STATUS", "return_payload": rpj}, 502) - except json.decoder.JSONDecodeError: - return {"reason": "NOT JSON", "return_payload": return_payload}, 502 - except KeyError: - return {"reason": "NO STATUS", "return_payload": rpj}, 502 + return _try_func_return(lambda: data.get_policy_type(policy_type_id)) -def _get_handler(policyname): +def delete_policy_type(policy_type_id): """ - Handles policy GET + Handles DELETE /a1-p/policytypes/policy_type_id """ - mtype_send, mtype_return = _get_needed_policy_fetch_info(policyname) - if not (mtype_send and mtype_return): - return "POLICY DOES NOT SUPPORT FETCHING", 400 + def delete_policy_type_handler(): + data.delete_policy_type(policy_type_id) + return "", 204 - # send rmr, wait for ACK - return_payload = a1rmr.send_ack_retry("", message_type=mtype_send, expected_ack_message_type=mtype_return) + return _try_func_return(delete_policy_type_handler) - # right now it is assumed that xapps respond with JSON payloads - try: - return (json.loads(return_payload), 200) - except json.decoder.JSONDecodeError: - return {"reason": "NOT JSON", "return_payload": return_payload}, 502 +# Policy instances -# Public + +def get_all_instances_for_type(policy_type_id): + """ + Handles GET /a1-p/policytypes/policy_type_id/policies + """ + return _try_func_return(lambda: data.get_instance_list(policy_type_id)) -def put_handler(policyname): +def get_policy_instance(policy_type_id, policy_instance_id): """ - Handles policy replacement + Handles GET /a1-p/policytypes/polidyid/policies/policy_instance_id """ - data = connexion.request.json - return _try_func_return(lambda: _put_handler(policyname, data)) + return _try_func_return(lambda: data.get_policy_instance(policy_type_id, policy_instance_id)) -def get_handler(policyname): +def get_policy_instance_status(policy_type_id, policy_instance_id): """ - Handles policy GET + Handles GET /a1-p/policytypes/polidyid/policies/policy_instance_id/status + + Return the aggregated status. The order of rules is as follows: + 1. If a1 has received at least one status, and *all* received statuses are "DELETED", we blow away the instance and return a 404 + 2. if a1 has received at least one status and at least one is OK, we return "IN EFFECT" + 3. "NOT IN EFFECT" otherwise (no statuses, or none are OK but not all are deleted) """ - return _try_func_return(lambda: _get_handler(policyname)) + + return _try_func_return(lambda: data.get_policy_instance_status(policy_type_id, policy_instance_id)) -def healthcheck_handler(): +def create_or_replace_policy_instance(policy_type_id, policy_instance_id): """ - Handles healthcheck GET - Currently, this basically checks the server is alive.a1rmr + Handles PUT /a1-p/policytypes/polidyid/policies/policy_instance_id """ - return "", 200 + instance = connexion.request.json + + def put_instance_handler(): + """ + Handles policy instance put + + For now, policy_type_id is used as the message type + """ + # validate the PUT against the schema + schema = data.get_policy_type(policy_type_id)["create_schema"] + validate(instance=instance, schema=schema) + + # store the instance + data.store_policy_instance(policy_type_id, policy_instance_id, instance) + + # queue rmr send (best effort) + a1rmr.queue_instance_send(("CREATE", policy_type_id, policy_instance_id, instance)) + + return "", 202 + + return _try_func_return(put_instance_handler) + + +def delete_policy_instance(policy_type_id, policy_instance_id): + """ + Handles DELETE /a1-p/policytypes/polidyid/policies/policy_instance_id + """ + + def delete_instance_handler(): + data.delete_policy_instance(policy_type_id, policy_instance_id) + + # queue rmr send (best effort) + a1rmr.queue_instance_send(("DELETE", policy_type_id, policy_instance_id, "")) + + return "", 202 + + return _try_func_return(delete_instance_handler)