We use dict data structures (KV) with the expectation of having to move this into Redis
"""
import json
+import msgpack
from a1.exceptions import PolicyTypeNotFound, PolicyInstanceNotFound, PolicyTypeAlreadyExists, CantDeleteNonEmptyType
from a1 import get_module_logger
from a1 import a1rmr
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"
+
+class SDLWrapper:
+ """
+ This is a wrapper around the expected SDL Python interface.
+ The usage of POLICY_DATA will be replaced with SDL when SDL for python is available.
+ The eventual SDL API is expected to be very close to what is here.
+
+ We use msgpack for binary (de)serialization: https://msgpack.org/index.html
+ """
+
+ def __init__(self):
+ self.POLICY_DATA = {}
+
+ def set(self, key, value):
+ """set a key"""
+ self.POLICY_DATA[key] = msgpack.packb(value, use_bin_type=True)
+
+ def get(self, key):
+ """get a key"""
+ if key in self.POLICY_DATA:
+ return msgpack.unpackb(self.POLICY_DATA[key], raw=False)
+ return None
+
+ def find_and_get(self, prefix):
+ """get all k v pairs that start with prefix"""
+ return {k: msgpack.unpackb(v, raw=False) for k, v in self.POLICY_DATA.items() if k.startswith(prefix)}
+
+ def delete(self, key):
+ """ delete a key"""
+ del self.POLICY_DATA[key]
+
+
+SDL = SDLWrapper()
+
+TYPE_PREFIX = "a1.policy_type."
+INSTANCE_PREFIX = "a1.policy_instance."
+HANDLER_PREFIX = "a1.policy_handler."
# 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 _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_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 _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)
- return [v for _, v in POLICY_DATA[policy_type_id][I][policy_instance_id][H].items()]
+ prefixes_for_handler = "{0}{1}.{2}.".format(HANDLER_PREFIX, policy_type_id, policy_instance_id)
+ return list(SDL.find_and_get(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)
- return list(POLICY_DATA[policy_type_id][I].keys())
+ prefixes_for_type = "{0}{1}.".format(INSTANCE_PREFIX, policy_type_id)
+ instancekeys = SDL.find_and_get(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(all_handlers_pref)
+ for k in keys:
+ SDL.delete(k)
def _clean_up_type(policy_type_id):
# try to parse the messages as responses. Drop those that are malformed
pay = json.loads(msg["payload"])
if "policy_type_id" in pay and "policy_instance_id" in pay and "handler_id" in pay and "status" in pay:
- """
- NOTE: can't raise an exception here e.g.:
- instance_is_valid(pti, pii)
- because this is called on many functions; just drop bad status messages.
- We def don't want bad messages that happen to hit a1s mailbox to blow up anything
-
- NOTE2: we don't use the parameters "policy_type_id, policy_instance" from above here,
+ # We don't use the parameters "policy_type_id, policy_instance" from above here,
# because we are popping the whole mailbox, which might include other statuses
- """
pti = pay["policy_type_id"]
pii = pay["policy_instance_id"]
- if pti in POLICY_DATA and pii in POLICY_DATA[pti][I]: # manual check per comment above
- POLICY_DATA[pti][I][pii][H][pay["handler_id"]] = pay["status"]
+
+ try:
+ """
+ can't raise an exception here e.g.:
+ because this is called on many functions; just drop bad status messages.
+ We def don't want bad messages that happen to hit a1s mailbox to blow up anything
+
+ """
+ type_is_valid(pti)
+ instance_is_valid(pti, pii)
+ SDL.set(_generate_handler_key(pti, pii, pay["handler_id"]), pay["status"])
+ except (PolicyTypeNotFound, PolicyInstanceNotFound):
+ pass
+
else:
logger.debug("Dropping message")
logger.debug(pay)
# blow away from a1 db
if all_deleted:
- del POLICY_DATA[policy_type_id][I][policy_instance_id]
+ _clear_handlers(policy_type_id, policy_instance_id) # delete all the handlers
+ SDL.delete(_generate_instance_key(policy_type_id, policy_instance_id)) # delete instance
# Types
"""
retrieve all type ids
"""
- return list(POLICY_DATA.keys())
+ typekeys = SDL.find_and_get(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 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(_generate_type_key(policy_type_id)) is None:
raise PolicyTypeNotFound()
"""
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(key) is not None:
raise PolicyTypeAlreadyExists()
-
- POLICY_DATA[policy_type_id] = {}
- POLICY_DATA[policy_type_id][D] = body
- POLICY_DATA[policy_type_id][I] = {}
+ SDL.set(key, body)
def delete_policy_type(policy_type_id):
"""
pil = get_instance_list(policy_type_id)
if pil == []: # empty, can delete
- del POLICY_DATA[policy_type_id]
+ SDL.delete(_generate_type_key(policy_type_id))
else:
raise CantDeleteNonEmptyType()
retrieve a type
"""
type_is_valid(policy_type_id)
- return POLICY_DATA[policy_type_id][D]
+ return SDL.get(_generate_type_key(policy_type_id))
# Instances
check that an instance is valid
"""
type_is_valid(policy_type_id)
- if policy_instance_id not in POLICY_DATA[policy_type_id][I]:
+ if SDL.get(_generate_instance_key(policy_type_id, policy_instance_id)) is None:
raise PolicyInstanceNotFound
Store a policy instance
"""
type_is_valid(policy_type_id)
-
- # 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(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(key, instance)
def get_policy_instance(policy_type_id, policy_instance_id):
"""
_clean_up_type(policy_type_id)
instance_is_valid(policy_type_id, policy_instance_id)
- return POLICY_DATA[policy_type_id][I][policy_instance_id][D]
+ return SDL.get(_generate_instance_key(policy_type_id, policy_instance_id))
def get_policy_instance_statuses(policy_type_id, policy_instance_id):
Code Review / ric-plt / a1.git / blobdiff