X-Git-Url: https://gerrit.o-ran-sc.org/r/gitweb?a=blobdiff_plain;f=a1%2Fdata.py;h=45fe5de204e27f52d529fb8a9c671b6f367ac072;hb=2c1c4e9dd207289bbdc3453bfdb3e2dad68df8a8;hp=6fa8b3f9033bca4bac8da70da4bae84d05170df3;hpb=91ae88989c82b08b9fb69a28f838d6b80681d953;p=ric-plt%2Fa1.git diff --git a/a1/data.py b/a1/data.py index 6fa8b3f..45fe5de 100644 --- a/a1/data.py +++ b/a1/data.py @@ -1,6 +1,9 @@ +""" +Represents A1s database and database access functions. +""" # ================================================================================== -# 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. @@ -14,108 +17,265 @@ # See the License for the specific language governing permissions and # limitations under the License. # ================================================================================== +import os +import time +from threading import Thread +from mdclogpy import Logger +from ricxappframe.xapp_sdl import SDLWrapper +from a1.exceptions import PolicyTypeNotFound, PolicyInstanceNotFound, PolicyTypeAlreadyExists, CantDeleteNonEmptyType -""" -Represents A1s database and database access functions. -In the future, this may change to use a different backend, possibly dramatically. -Hopefully, the access functions are a good api so nothing else has to change when this happens -For now, the database is in memory. -We use dict data structures (KV) with the expectation of having to move this into Redis -""" -from a1.exceptions import PolicyTypeNotFound, PolicyInstanceNotFound, PolicyTypeAlreadyExists -from a1 import get_module_logger +# constants +INSTANCE_DELETE_NO_RESP_TTL = int(os.environ.get("INSTANCE_DELETE_NO_RESP_TTL", 5)) +INSTANCE_DELETE_RESP_TTL = int(os.environ.get("INSTANCE_DELETE_RESP_TTL", 5)) +A1NS = "A1m_ns" +TYPE_PREFIX = "a1.policy_type." +INSTANCE_PREFIX = "a1.policy_instance." +METADATA_PREFIX = "a1.policy_inst_metadata." +HANDLER_PREFIX = "a1.policy_handler." -logger = get_module_logger(__name__) -# This is essentially mockouts for future KV -# Note that the D subkey won't be needed when in redis, since you can store data at x anx x_y -POLICY_DATA = {} -I = "instances" -H = "handlers" -D = "data" +mdc_logger = Logger(name=__name__) +SDL = SDLWrapper() -# Types +# Internal helpers + + +def _generate_type_key(policy_type_id): + """ + generate a key for a policy type + """ + return "{0}{1}".format(TYPE_PREFIX, policy_type_id) -def type_is_valid(policy_type_id): +def _generate_instance_key(policy_type_id, policy_instance_id): + """ + generate a key for a policy instance + """ + return "{0}{1}.{2}".format(INSTANCE_PREFIX, policy_type_id, policy_instance_id) + + +def _generate_instance_metadata_key(policy_type_id, policy_instance_id): + """ + generate a key for a policy instance metadata + """ + return "{0}{1}.{2}".format(METADATA_PREFIX, policy_type_id, policy_instance_id) + + +def _generate_handler_prefix(policy_type_id, policy_instance_id): + """ + generate the prefix to a handler key + """ + return "{0}{1}.{2}.".format(HANDLER_PREFIX, policy_type_id, policy_instance_id) + + +def _generate_handler_key(policy_type_id, policy_instance_id, handler_id): + """ + generate a key for a policy handler + """ + return "{0}{1}".format(_generate_handler_prefix(policy_type_id, policy_instance_id), handler_id) + + +def _type_is_valid(policy_type_id): """ check that a type is valid """ - if policy_type_id not in POLICY_DATA: - logger.error("%s not found", policy_type_id) + if SDL.get(A1NS, _generate_type_key(policy_type_id)) is None: raise PolicyTypeNotFound() +def _instance_is_valid(policy_type_id, policy_instance_id): + """ + check that an instance is valid + """ + _type_is_valid(policy_type_id) + if SDL.get(A1NS, _generate_instance_key(policy_type_id, policy_instance_id)) is None: + raise PolicyInstanceNotFound + + +def _get_statuses(policy_type_id, policy_instance_id): + """ + shared helper to get statuses for an instance + """ + _instance_is_valid(policy_type_id, policy_instance_id) + prefixes_for_handler = "{0}{1}.{2}.".format(HANDLER_PREFIX, policy_type_id, policy_instance_id) + return list(SDL.find_and_get(A1NS, prefixes_for_handler).values()) + + +def _get_instance_list(policy_type_id): + """ + shared helper to get instance list for a type + """ + _type_is_valid(policy_type_id) + prefixes_for_type = "{0}{1}.".format(INSTANCE_PREFIX, policy_type_id) + instancekeys = SDL.find_and_get(A1NS, prefixes_for_type).keys() + return [k.split(prefixes_for_type)[1] for k in instancekeys] + + +def _clear_handlers(policy_type_id, policy_instance_id): + """ + delete all the handlers for a policy instance + """ + all_handlers_pref = _generate_handler_prefix(policy_type_id, policy_instance_id) + keys = SDL.find_and_get(A1NS, all_handlers_pref) + for k in keys: + SDL.delete(A1NS, k) + + +def _get_metadata(policy_type_id, policy_instance_id): + """ + get instance metadata + """ + _instance_is_valid(policy_type_id, policy_instance_id) + metadata_key = _generate_instance_metadata_key(policy_type_id, policy_instance_id) + return SDL.get(A1NS, metadata_key) + + +def _delete_after(policy_type_id, policy_instance_id, ttl): + """ + this is a blocking function, must call this in a thread to not block! + waits ttl seconds, then deletes the instance + """ + _instance_is_valid(policy_type_id, policy_instance_id) + + time.sleep(ttl) + + # ready to delete + _clear_handlers(policy_type_id, policy_instance_id) # delete all the handlers + SDL.delete(A1NS, _generate_instance_key(policy_type_id, policy_instance_id)) # delete instance + SDL.delete(A1NS, _generate_instance_metadata_key(policy_type_id, policy_instance_id)) # delete instance metadata + mdc_logger.debug("type {0} instance {1} deleted".format(policy_type_id, policy_instance_id)) + + +# Types + + +def get_type_list(): + """ + retrieve all type ids + """ + typekeys = SDL.find_and_get(A1NS, TYPE_PREFIX).keys() + # policy types are ints but they get butchered to strings in the KV + return [int(k.split(TYPE_PREFIX)[1]) for k in typekeys] + + def store_policy_type(policy_type_id, body): """ store a policy type if it doesn't already exist """ - if policy_type_id in POLICY_DATA: + key = _generate_type_key(policy_type_id) + if SDL.get(A1NS, key) is not None: raise PolicyTypeAlreadyExists() + SDL.set(A1NS, key, body) - POLICY_DATA[policy_type_id] = {} - POLICY_DATA[policy_type_id][D] = body - POLICY_DATA[policy_type_id][I] = {} + +def delete_policy_type(policy_type_id): + """ + delete a policy type; can only be done if there are no instances (business logic) + """ + pil = get_instance_list(policy_type_id) + if pil == []: # empty, can delete + SDL.delete(A1NS, _generate_type_key(policy_type_id)) + else: + raise CantDeleteNonEmptyType() def get_policy_type(policy_type_id): """ retrieve a type """ - type_is_valid(policy_type_id) - return POLICY_DATA[policy_type_id][D] + _type_is_valid(policy_type_id) + return SDL.get(A1NS, _generate_type_key(policy_type_id)) # Instances -def instance_is_valid(policy_type_id, policy_instance_id): - """ - check that an instance is valid - """ - type_is_valid(policy_type_id) - if policy_instance_id not in POLICY_DATA[policy_type_id][I]: - raise PolicyInstanceNotFound - - def store_policy_instance(policy_type_id, policy_instance_id, instance): """ Store a policy instance """ - type_is_valid(policy_type_id) + _type_is_valid(policy_type_id) + creation_timestamp = time.time() # store the instance - # Reset the statuses because this is a new policy instance, even if it was overwritten - POLICY_DATA[policy_type_id][I][policy_instance_id] = {} - POLICY_DATA[policy_type_id][I][policy_instance_id][D] = instance - POLICY_DATA[policy_type_id][I][policy_instance_id][H] = {} + key = _generate_instance_key(policy_type_id, policy_instance_id) + if SDL.get(A1NS, key) is not None: + # Reset the statuses because this is a new policy instance, even if it was overwritten + _clear_handlers(policy_type_id, policy_instance_id) # delete all the handlers + SDL.set(A1NS, key, instance) + + metadata_key = _generate_instance_metadata_key(policy_type_id, policy_instance_id) + SDL.set(A1NS, metadata_key, {"created_at": creation_timestamp, "has_been_deleted": False}) def get_policy_instance(policy_type_id, policy_instance_id): """ Retrieve a policy instance """ - type_is_valid(policy_type_id) - instance_is_valid(policy_type_id, policy_instance_id) - return POLICY_DATA[policy_type_id][I][policy_instance_id][D] + _instance_is_valid(policy_type_id, policy_instance_id) + return SDL.get(A1NS, _generate_instance_key(policy_type_id, policy_instance_id)) -def get_policy_instance_statuses(policy_type_id, policy_instance_id): +def get_instance_list(policy_type_id): """ - Retrieve the status vector for a policy instance + retrieve all instance ids for a type """ - type_is_valid(policy_type_id) - instance_is_valid(policy_type_id, policy_instance_id) + return _get_instance_list(policy_type_id) - return [{"handler_id": k, "status": v} for k, v in POLICY_DATA[policy_type_id][I][policy_instance_id][H].items()] + +def delete_policy_instance(policy_type_id, policy_instance_id): + """ + initially sets has_been_deleted in the status + then launches a thread that waits until the relevent timer expires, and finally deletes the instance + """ + _instance_is_valid(policy_type_id, policy_instance_id) + + # set the metadata first + deleted_timestamp = time.time() + metadata_key = _generate_instance_metadata_key(policy_type_id, policy_instance_id) + existing_metadata = _get_metadata(policy_type_id, policy_instance_id) + SDL.set( + A1NS, + metadata_key, + {"created_at": existing_metadata["created_at"], "has_been_deleted": True, "deleted_at": deleted_timestamp}, + ) + + # wait, then delete + vector = _get_statuses(policy_type_id, policy_instance_id) + if vector == []: + # handler is empty; we wait for t1 to expire then goodnight + clos = lambda: _delete_after(policy_type_id, policy_instance_id, INSTANCE_DELETE_NO_RESP_TTL) + else: + # handler is not empty, we wait max t1,t2 to expire then goodnight + clos = lambda: _delete_after( + policy_type_id, policy_instance_id, max(INSTANCE_DELETE_RESP_TTL, INSTANCE_DELETE_NO_RESP_TTL) + ) + Thread(target=clos).start() + + +# Statuses def set_policy_instance_status(policy_type_id, policy_instance_id, handler_id, status): """ - Update the status of a handler id of a policy instance + update the database status for a handler + called from a1's rmr thread """ - type_is_valid(policy_type_id) - instance_is_valid(policy_type_id, policy_instance_id) + _type_is_valid(policy_type_id) + _instance_is_valid(policy_type_id, policy_instance_id) + SDL.set(A1NS, _generate_handler_key(policy_type_id, policy_instance_id, handler_id), status) + - POLICY_DATA[policy_type_id][I][policy_instance_id][H][handler_id] = status +def get_policy_instance_status(policy_type_id, policy_instance_id): + """ + Gets the status of an instance + """ + _instance_is_valid(policy_type_id, policy_instance_id) + metadata = _get_metadata(policy_type_id, policy_instance_id) + metadata["instance_status"] = "NOT IN EFFECT" + for i in _get_statuses(policy_type_id, policy_instance_id): + if i == "OK": + metadata["instance_status"] = "IN EFFECT" + break + return metadata