def get_permissions(actor_id):
""" Return all permissions for an actor
:param actor_id:
:return:
"""
try:
return permissions_store[actor_id]
except KeyError:
raise errors.PermissionsException("Actor {} does not exist".format(actor_id))
def check_and_redeem_nonce(cls, actor_id, nonce_id, level):
"""
Atomically, check for the existence of a nonce for a given actor_id and redeem it if it
has not expired. Otherwise, raises PermissionsError.
"""
def _transaction(nonces):
"""
This function can be passed to nonce_store.within_transaction() to atomically check
whether a nonce is expired and, if not, redeem a use. The parameter, nonces, should
be the value under the key `actor_id` associated with the nonce.
"""
# first pull the nonce from the nonces parameter
try:
nonce = nonces[nonce_id]
except KeyError:
raise errors.PermissionsException("Nonce does not exist.")
# check if the nonce level is sufficient
try:
if PermissionLevel(nonce['level']) < level:
raise errors.PermissionsException(
"Nonce does not have sufficient permissions level.")
except KeyError:
raise errors.PermissionsException(
"Nonce did not have an associated level.")
# check if there are remaining uses
try:
if nonce['remaining_uses'] == -1:
logger.debug("nonce has infinite uses. updating nonce.")
nonce['current_uses'] += 1
nonce['last_use_time'] = get_current_utc_time()
nonce_store.update(actor_id, nonce_id, nonce)
elif nonce['remaining_uses'] > 0:
logger.debug(
"nonce still has uses remaining. updating nonce.")
nonce['current_uses'] += 1
nonce['remaining_uses'] -= 1
nonce_store.update(actor_id, nonce_id, nonce)
else:
logger.debug(
"nonce did not have at least 1 use remaining.")
raise errors.PermissionsException(
"No remaining uses left for this nonce.")
except KeyError:
logger.debug("nonce did not have a remaining_uses attribute.")
raise errors.PermissionsException(
"No remaining uses left for this nonce.")
# first, make sure the nonce exists for the actor id:
try:
nonce_store[actor_id][nonce_id]
except KeyError:
raise errors.PermissionsException("Nonce does not exist.")
# atomically, check if the nonce is still valid and add a use if so:
nonce_store.within_transaction(_transaction, actor_id)