diff options
Diffstat (limited to 'policyhandler/pdp_api_v0/policy_utils.py')
| -rw-r--r-- | policyhandler/pdp_api_v0/policy_utils.py | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/policyhandler/pdp_api_v0/policy_utils.py b/policyhandler/pdp_api_v0/policy_utils.py new file mode 100644 index 0000000..d337665 --- /dev/null +++ b/policyhandler/pdp_api_v0/policy_utils.py @@ -0,0 +1,120 @@ +# ================================================================================ +# Copyright (c) 2018-2019 AT&T Intellectual Property. All rights reserved. +# ================================================================================ +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# ============LICENSE_END========================================================= +# + +"""utils for policy usage and conversions""" + +import re + +from ..policy_consts import POLICY_BODY, POLICY_ID +from ..utils import Utils +from .pdp_consts import POLICY_CONFIG, POLICY_NAME, POLICY_VERSION + + +class PolicyUtils(object): + """policy-client utils""" + _policy_name_ext = re.compile('[.][0-9]+[.][a-zA-Z]+$') + + @staticmethod + def extract_policy_id(policy_name): + """ policy_name = policy_id + "." + <version> + "." + <extension> + For instance, + policy_name = DCAE_alex.Config_alex_policy_number_1.3.xml + policy_id = DCAE_alex.Config_alex_policy_number_1 + policy_scope = DCAE_alex + policy_class = Config + policy_version = 3 + type = extension = xml + delimiter = "." + policy_class_delimiter = "_" + policy_name in PAP = DCAE_alex.alex_policy_number_1 + """ + if not policy_name: + return + return PolicyUtils._policy_name_ext.sub('', policy_name) + + @staticmethod + def parse_policy_config(policy): + """try parsing the config in policy.""" + if not policy: + return policy + config = policy.get(POLICY_BODY, {}).get(POLICY_CONFIG) + if config: + policy[POLICY_BODY][POLICY_CONFIG] = Utils.safe_json_parse(config) + return policy + + @staticmethod + def convert_to_policy(policy_body): + """wrap policy_body received from policy-engine with policy_id.""" + if not policy_body: + return None + policy_name = policy_body.get(POLICY_NAME) + policy_version = policy_body.get(POLICY_VERSION) + if not policy_name or not policy_version: + return None + policy_id = PolicyUtils.extract_policy_id(policy_name) + if not policy_id: + return None + return {POLICY_ID:policy_id, POLICY_BODY:policy_body} + + @staticmethod + def select_latest_policy(policy_bodies, expected_versions=None, ignore_policy_names=None): + """For some reason, the policy-engine returns all version of the policy_bodies. + DCAE-Controller is only interested in the latest version + """ + if not policy_bodies: + return + latest_policy_body = {} + for policy_body in policy_bodies: + policy_name = policy_body.get(POLICY_NAME) + policy_version = policy_body.get(POLICY_VERSION) + if not policy_name or not policy_version or not policy_version.isdigit(): + continue + if expected_versions and policy_version not in expected_versions: + continue + if ignore_policy_names and policy_name in ignore_policy_names: + continue + + if (not latest_policy_body + or int(latest_policy_body[POLICY_VERSION]) < int(policy_version)): + latest_policy_body = policy_body + + return PolicyUtils.parse_policy_config(PolicyUtils.convert_to_policy(latest_policy_body)) + + @staticmethod + def select_latest_policies(policy_bodies): + """For some reason, the policy-engine returns all version of the policy_bodies. + DCAE-Controller is only interested in the latest versions + """ + if not policy_bodies: + return {} + policies = {} + for policy_body in policy_bodies: + policy = PolicyUtils.convert_to_policy(policy_body) + if not policy: + continue + policy_id = policy.get(POLICY_ID) + policy_version = policy.get(POLICY_BODY, {}).get(POLICY_VERSION) + if not policy_id or not policy_version or not policy_version.isdigit(): + continue + if (policy_id not in policies + or int(policy_version) > int(policies[policy_id][POLICY_BODY][POLICY_VERSION])): + policies[policy_id] = policy + + for policy_id in policies: + policies[policy_id] = PolicyUtils.parse_policy_config(policies[policy_id]) + + return policies |