policy-handler seed code

Change-Id: I35cd80b6e082f4b84740bab752774e8abc40ca35
Issue-Id: DCAEGEN2-46
Signed-off-by: Alex Shatov <alexs@att.com>

1 files changed, 100 insertions, 0 deletions

diff --git a/policyhandler/policy_engine.py b/policyhandler/policy_engine.py
new file mode 100644
index 0000000..838ccc7
--- /dev/null
+++ b/policyhandler/policy_engine.py
@@ -0,0 +1,100 @@
+"""policy-engine-client communicates with policy-engine thru PolicyEngine client object"""
+
+# 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 re
+
+from .config import Config, PolicyEngineConfig
+from .onap.audit import Audit
+from .PolicyEngine import PolicyEngine, NotificationHandler, NotificationScheme
+from .policy_updater import PolicyUpdater
+
+class PolicyNotificationHandler(NotificationHandler):
+    """handler of the policy-engine push notifications"""
+    _logger = logging.getLogger("policy_handler.policy_notification")
+
+    def __init__(self, policy_updater):
+        scope_prefixes = [scope_prefix.replace(".", "[.]") \
+                          for scope_prefix in Config.config["scope_prefixes"]]
+        self._policy_scopes = re.compile("(" + "|".join(scope_prefixes) + ")")
+        PolicyNotificationHandler._logger.info("_policy_scopes %s", self._policy_scopes.pattern)
+        self._policy_updater = policy_updater
+        self._policy_updater.start()
+
+    def notificationReceived(self, notification):
+        if not notification or not notification._loadedPolicies:
+            return
+
+        policy_names = [loaded._policyName \
+            for loaded in notification._loadedPolicies \
+            if self._policy_scopes.match(loaded._policyName)]
+
+        if not policy_names:
+            PolicyNotificationHandler._logger.info("no policy updated for scopes %s", \
+                self._policy_scopes.pattern)
+            return
+
+        audit = Audit(req_message="notificationReceived from PDP")
+        audit.retry_get_config = True
+        self._policy_updater.enqueue(audit, policy_names)
+
+class PolicyEngineClient(object):
+    """ policy-engine client"""
+    _logger = logging.getLogger("policy_handler.policy_engine")
+    _policy_updater = None
+    _pdp_notification_handler = None
+    _policy_engine = None
+
+    @staticmethod
+    def shutdown(audit):
+        """Shutdown the notification-handler"""
+        PolicyEngineClient._policy_updater.shutdown(audit)
+
+    @staticmethod
+    def catch_up(audit):
+        """bring the latest policies from policy-engine"""
+        PolicyEngineClient._policy_updater.catch_up(audit)
+
+    @staticmethod
+    def create_policy_engine_properties():
+        """create the policy_engine.properties file from config.json"""
+        pass
+
+    @staticmethod
+    def run():
+        """Using policy-engine client to talk to policy engine"""
+        audit = Audit(req_message="start PDP client")
+        PolicyEngineClient._policy_updater = PolicyUpdater()
+        PolicyEngineClient._pdp_notification_handler = PolicyNotificationHandler(
+            PolicyEngineClient._policy_updater)
+
+        sub_aud = Audit(aud_parent=audit)
+        sub_aud.metrics_start("create client to PDP")
+        PolicyEngineConfig.save_to_file()
+        PolicyEngineClient._policy_engine = PolicyEngine(PolicyEngineConfig.PATH_TO_PROPERTIES, \
+                                            scheme=NotificationScheme.AUTO_ALL_NOTIFICATIONS.name,\
+                                            handler=PolicyEngineClient._pdp_notification_handler)
+        sub_aud.metrics("created client to PDP")
+        seed_scope = Config.config["scope_prefixes"][0] + ".*"
+        PolicyEngineClient._policy_engine.getConfig(policyName=seed_scope)
+        sub_aud.metrics("seeded client by PDP.getConfig for policyName={0}".format(seed_scope))
+
+        PolicyEngineClient.catch_up(audit)