Handle AAI Update and Delete events for PMSH

Change-Id: I7f84e4429011bbaea4de23077ce23629b897fd7d
Issue-ID: DCAEGEN2-1846
Signed-off-by: emartin <ephraim.martin@est.tech>

1 files changed, 90 insertions, 0 deletions

diff --git a/components/pm-subscription-handler/pmsh_service/mod/aai_event_handler.py b/components/pm-subscription-handler/pmsh_service/mod/aai_event_handler.py
new file mode 100755
index 00000000..f8254e52
--- /dev/null
+++ b/components/pm-subscription-handler/pmsh_service/mod/aai_event_handler.py
@@ -0,0 +1,90 @@
+# ============LICENSE_START===================================================
+#  Copyright (C) 2020 Nordix Foundation.
+# ============================================================================
+# 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.
+#
+# SPDX-License-Identifier: Apache-2.0
+# ============LICENSE_END=====================================================
+
+import json
+from enum import Enum
+
+from mod import pmsh_logging as logger
+from mod.network_function import NetworkFunction
+from mod.subscription import NetworkFunctionFilter
+
+
+class XNFType(Enum):
+    PNF = 'pnf'
+    VNF = 'vnf'
+
+
+class AAIEvent(Enum):
+    DELETE = 'DELETE'
+    UPDATE = 'UPDATE'
+
+
+class OrchestrationStatus(Enum):
+    ACTIVE = 'Active'
+    INVENTORIED = 'Inventoried'
+
+
+def process_aai_events(mr_sub, subscription, mr_pub, app):
+    """
+    Processes AAI UPDATE events for each filtered xNFs where orchestration status is set to Active.
+
+    Args:
+        mr_sub (_MrSub): MR subscriber
+        subscription (Subscription): The current subscription object
+        mr_pub (_MrPub): MR publisher
+        app (db): DB application
+    """
+    app.app_context().push()
+    aai_events = mr_sub.get_from_topic('AAI-EVENT')
+
+    if _aai_event_exists(aai_events):
+        for entry in aai_events:
+            logger.debug(f'AAI-EVENT entry: {entry}')
+            entry = json.loads(entry)
+            event_header = entry['event-header']
+            aai_xnf = entry['entity']
+            action = event_header['action']
+            entity_type = event_header['entity-type']
+            xnf_name = aai_xnf['pnf-name'] if entity_type == XNFType.PNF.value else aai_xnf[
+                'vnf-name']
+            new_status = aai_xnf['orchestration-status']
+
+            if NetworkFunctionFilter(**subscription.nfFilter).is_nf_in_filter(xnf_name):
+                _process_event(action, new_status, xnf_name, subscription, mr_pub)
+
+
+def _process_event(action, new_status, xnf_name, subscription, mr_pub):
+    if action == AAIEvent.UPDATE.value:
+        logger.debug(f'Update event found for network function {xnf_name}')
+        local_xnf = NetworkFunction.get(xnf_name)
+
+        if local_xnf is None:
+            logger.debug(f'Activating subscription for network function {xnf_name}')
+            subscription.process_subscription([NetworkFunction(
+                nf_name=xnf_name, orchestration_status=new_status)], mr_pub)
+        else:
+            logger.debug(f"Update Event for network function {xnf_name} will not be processed "
+                         f" as it's state is set to {local_xnf.orchestration_status}.")
+    elif action == AAIEvent.DELETE.value:
+        logger.debug(f'Delete event found for network function {xnf_name}')
+        NetworkFunction.delete(nf_name=xnf_name)
+        logger.debug(f'{xnf_name} successfully deleted.')
+
+
+def _aai_event_exists(aai_events):
+    return aai_events is not None and len(aai_events) != 0