variable collection of policies per component
* new feature variable collection of policies per component in DCAE
* massive refactoring
* dissolved the external PolicyEngine.py into policy_receiver.py
- kept only the web-socket communication to PolicyEngine
* new /healthcheck - shows some stats of service running
* Unit Test coverage 75%
Change-Id: I816b7d5713ae0dd88fa73d3656f272b4f3e7946e
Issue-ID: DCAEGEN2-249
Signed-off-by: Alex Shatov <alexs@att.com>
diff --git a/policyhandler/policy_utils.py b/policyhandler/policy_utils.py
new file mode 100644
index 0000000..d664b21
--- /dev/null
+++ b/policyhandler/policy_utils.py
@@ -0,0 +1,134 @@
+"""policy-client communicates with policy-engine thru REST API"""
+
+# org.onap.dcae
+# ================================================================================
+# Copyright (c) 2017 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=========================================================
+#
+# ECOMP is a trademark and service mark of AT&T Intellectual Property.
+
+import logging
+import json
+import re
+
+from .policy_consts import POLICY_ID, POLICY_VERSION, POLICY_NAME, POLICY_BODY, POLICY_CONFIG
+
+class PolicyUtils(object):
+ """policy-client utils"""
+ _logger = logging.getLogger("policy_handler.policy_utils")
+ _policy_name_ext = re.compile('[.][0-9]+[.][a-zA-Z]+$')
+
+ @staticmethod
+ def safe_json_parse(json_str):
+ """try parsing json without exception - returns the json_str back if fails"""
+ if not json_str:
+ return json_str
+ try:
+ return json.loads(json_str)
+ except (ValueError, TypeError) as err:
+ PolicyUtils._logger.warn("unexpected json %s: %s", str(json_str), str(err))
+ return json_str
+
+ @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] = PolicyUtils.safe_json_parse(config)
+ return policy
+
+ @staticmethod
+ def convert_to_policy(policy_config):
+ """wrap policy_config received from policy-engine with policy_id."""
+ if not policy_config:
+ return
+ policy_name = policy_config.get(POLICY_NAME)
+ policy_version = policy_config.get(POLICY_VERSION)
+ if not policy_name or not policy_version:
+ return
+ policy_id = PolicyUtils.extract_policy_id(policy_name)
+ if not policy_id:
+ return
+ return {POLICY_ID:policy_id, POLICY_BODY:policy_config}
+
+ @staticmethod
+ def select_latest_policy(policy_configs, min_version_expected=None, ignore_policy_names=None):
+ """For some reason, the policy-engine returns all version of the policy_configs.
+ DCAE-Controller is only interested in the latest version
+ """
+ if not policy_configs:
+ return
+ latest_policy_config = {}
+ for policy_config in policy_configs:
+ policy_name = policy_config.get(POLICY_NAME)
+ policy_version = policy_config.get(POLICY_VERSION)
+ if not policy_name or not policy_version or not policy_version.isdigit():
+ continue
+ policy_version = int(policy_version)
+ if min_version_expected and policy_version < min_version_expected:
+ continue
+ if ignore_policy_names and policy_name in ignore_policy_names:
+ continue
+
+ if not latest_policy_config \
+ or int(latest_policy_config[POLICY_VERSION]) < policy_version:
+ latest_policy_config = policy_config
+
+ return PolicyUtils.parse_policy_config(PolicyUtils.convert_to_policy(latest_policy_config))
+
+ @staticmethod
+ def select_latest_policies(policy_configs):
+ """For some reason, the policy-engine returns all version of the policy_configs.
+ DCAE-Controller is only interested in the latest versions
+ """
+ if not policy_configs:
+ return {}
+ policies = {}
+ for policy_config in policy_configs:
+ policy = PolicyUtils.convert_to_policy(policy_config)
+ 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