Add Support for Activation and Deactivation

* Add support for reconfiguration of the administrativeState field
* Add support for policy feedback handling
* Fix network function filter applying to non active network functions

Signed-off-by: ERIMROB <robertas.rimkus@est.tech>
Change-Id: Ic1cfc3207b2495c1d8d10acd0ed1c40114cf4643
Issue-ID: DCAEGEN2-1830

8 files changed, 270 insertions, 77 deletions

diff --git a/components/pm-subscription-handler/pmsh_service/mod/aai_client.py b/components/pm-subscription-handler/pmsh_service/mod/aai_client.py
index 747846f1..f0f20566 100755
--- a/components/pm-subscription-handler/pmsh_service/mod/aai_client.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/aai_client.py
@@ -119,10 +119,12 @@ def _filter_nf_data(nf_data, nf_filter):
     try:
         for nf in nf_data['results']:
             name_identifier = 'pnf-name' if nf['node-type'] == 'pnf' else 'vnf-name'
-            if nf_filter.is_nf_in_filter(nf['properties'].get(name_identifier)):
+            orchestration_status = nf['properties'].get('orchestration-status')
+            if nf_filter.is_nf_in_filter(nf['properties'].get(name_identifier)) \
+                    and orchestration_status == 'Active':
                 nf_set.add(NetworkFunction(
                     nf_name=nf['properties'].get(name_identifier),
-                    orchestration_status=nf['properties'].get('orchestration-status')))
+                    orchestration_status=orchestration_status))
     except KeyError as e:
         logger.debug(f'Failed to parse AAI data: {e}')
         raise
diff --git a/components/pm-subscription-handler/pmsh_service/mod/config_handler.py b/components/pm-subscription-handler/pmsh_service/mod/config_handler.py
index 1ce4b701..acf5b76f 100755
--- a/components/pm-subscription-handler/pmsh_service/mod/config_handler.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/config_handler.py
@@ -15,12 +15,10 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 # ============LICENSE_END=====================================================
-
-import json
 from os import environ
 
 import requests
-from tenacity import retry, wait_fixed, stop_after_attempt
+from tenacity import retry, wait_fixed, stop_after_attempt, retry_if_exception_type
 
 import mod.pmsh_logging as logger
 
@@ -45,7 +43,7 @@ class ConfigHandler:
     def hostname(self):
         return _get_environment_variable('HOSTNAME')
 
-    @retry(wait=wait_fixed(2), stop=stop_after_attempt(5))
+    @retry(wait=wait_fixed(2), stop=stop_after_attempt(5), retry=retry_if_exception_type(Exception))
     def get_config(self):
         """ Retrieves PMSH's configuration from Configbinding service. If a non-2xx response
         is received, it retries after 2 seconds for 5 times before raising an exception.
@@ -56,18 +54,15 @@ class ConfigHandler:
         Raises:
             Exception: If any error occurred pulling configuration from Configbinding service.
         """
-        if self._config is None:
-            logger.debug('No configuration found, pulling from Configbinding Service.')
-            try:
-                response = requests.get(self.cbs_url)
-                response.raise_for_status()
-                self._config = response.json()
-                logger.debug(f'PMSH Configuration from Configbinding Service: {self._config}')
-                return json.loads(self._config)
-            except Exception as err:
-                raise Exception(f'Error retrieving configuration from CBS: {err}')
-        else:
+
+        try:
+            response = requests.get(self.cbs_url)
+            response.raise_for_status()
+            self._config = response.json()
+            logger.debug(f'PMSH Configuration from Configbinding Service: {self._config}')
             return self._config
+        except Exception as err:
+            raise Exception(f'Error retrieving configuration from CBS: {err}')
 
 
 def _get_environment_variable(env_var_key):
diff --git a/components/pm-subscription-handler/pmsh_service/mod/network_function.py b/components/pm-subscription-handler/pmsh_service/mod/network_function.py
index 64f614af..9f21cc66 100755
--- a/components/pm-subscription-handler/pmsh_service/mod/network_function.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/network_function.py
@@ -15,16 +15,13 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 # ============LICENSE_END=====================================================
-
 from mod import pmsh_logging as logger, db
 from mod.db_models import NetworkFunctionModel
 
 
 class NetworkFunction:
     def __init__(self, **kwargs):
-        """
-        Object representation of the NetworkFunction.
-        """
+        """ Object representation of the NetworkFunction. """
         self.nf_name = kwargs.get('nf_name')
         self.orchestration_status = kwargs.get('orchestration_status')
 
@@ -36,8 +33,7 @@ class NetworkFunction:
         return f'nf-name: {self.nf_name}, orchestration-status: {self.orchestration_status}'
 
     def create(self):
-        """ Creates a NetworkFunction database entry
-        """
+        """ Creates a NetworkFunction database entry """
         existing_nf = NetworkFunctionModel.query.filter(
             NetworkFunctionModel.nf_name == self.nf_name).one_or_none()
 
@@ -71,3 +67,13 @@ class NetworkFunction:
             list: NetworkFunctionModel objects else empty
         """
         return NetworkFunctionModel.query.all()
+
+    @staticmethod
+    def delete(**kwargs):
+        """ Deletes a network function from the database """
+        nf_name = kwargs['nf_name']
+        NetworkFunctionModel.query.filter(
+            NetworkFunctionModel.nf_name == nf_name). \
+            delete(synchronize_session='evaluate')
+
+        db.session.commit()
diff --git a/components/pm-subscription-handler/pmsh_service/mod/pmsh_logging.py b/components/pm-subscription-handler/pmsh_service/mod/pmsh_logging.py
index f2d11d49..885644b4 100644
--- a/components/pm-subscription-handler/pmsh_service/mod/pmsh_logging.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/pmsh_logging.py
@@ -1,5 +1,5 @@
 # ============LICENSE_START===================================================
-#  Copyright (C) 2019 Nordix Foundation.
+#  Copyright (C) 2019-2020 Nordix Foundation.
 # ============================================================================
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -15,11 +15,10 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 # ============LICENSE_END=====================================================
-
+import datetime
 import logging as log
 from logging.handlers import RotatingFileHandler
 from os import makedirs
-import datetime
 
 # These loggers will be overwritten with EELF logging when running in Docker
 _AUDIT_LOGGER = log.getLogger("defaultlogger")
diff --git a/components/pm-subscription-handler/pmsh_service/mod/pmsh_utils.py b/components/pm-subscription-handler/pmsh_service/mod/pmsh_utils.py
index b665691d..4a77543b 100755
--- a/components/pm-subscription-handler/pmsh_service/mod/pmsh_utils.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/pmsh_utils.py
@@ -15,12 +15,17 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 # ============LICENSE_END=====================================================
+import json
+import threading
 import uuid
 
 import requests
 from requests.auth import HTTPBasicAuth
+from tenacity import retry, wait_fixed, retry_if_exception_type
 
 import mod.pmsh_logging as logger
+from mod.subscription import Subscription, SubNfState, AdministrativeState
+from mod.network_function import NetworkFunction
 
 
 class AppConfig:
@@ -168,3 +173,71 @@ class _MrSub(_DmaapMrClient):
         except Exception as e:
             logger.debug(e)
         return topic_data
+
+    @staticmethod
+    def _handle_response(subscription_name, administrative_state, nf_name, response_message):
+        """
+        Handles the response from Policy, updating the DB
+
+        Args:
+            subscription_name (str): The subscription name
+            administrative_state (str): The administrative state of the subscription
+            nf_name (str): The network function name
+            response_message (str): The message in the response regarding the state (success|failed)
+        """
+        logger.debug(f'Response from MR: Sub: {subscription_name} for '
+                     f'NF: {nf_name} received, updating the DB')
+        try:
+            sub_nf_status = subscription_nf_states[administrative_state][response_message].value
+            policy_response_handle_functions[administrative_state][response_message](
+                subscription_name=subscription_name, status=sub_nf_status, nf_name=nf_name)
+        except Exception as err:
+            raise Exception(f'Error changing nf_sub status in the DB: {err}')
+
+    @retry(wait=wait_fixed(5), retry=retry_if_exception_type(Exception))
+    def poll_policy_topic(self, subscription_name, app):
+        """
+        This method polls MR for response from policy. It checks whether the message is for the
+        relevant subscription and then handles the response
+
+        Args:
+            subscription_name (str): The subscription name
+            app (app): Needed to push context for the db
+        """
+        app.app_context().push()
+        administrative_state = Subscription.get(subscription_name).status
+        try:
+            response_data = self.get_from_topic('policy_response_consumer')
+            for data in response_data:
+                data = json.loads(data)
+                if data['status']['subscriptionName'] == subscription_name:
+                    nf_name = data['status']['nfName']
+                    response_message = data['status']['message']
+                    self._handle_response(subscription_name, administrative_state,
+                                          nf_name, response_message)
+            threading.Timer(5, self.poll_policy_topic, [subscription_name, app]).start()
+        except Exception as err:
+            raise Exception(f'Error trying to poll MR: {err}')
+
+
+subscription_nf_states = {
+    AdministrativeState.LOCKED.value: {
+        'success': SubNfState.CREATED,
+        'failed': SubNfState.DELETE_FAILED
+    },
+    AdministrativeState.UNLOCKED.value: {
+        'success': SubNfState.CREATED,
+        'failed': SubNfState.CREATE_FAILED
+    }
+}
+
+policy_response_handle_functions = {
+    AdministrativeState.LOCKED.value: {
+        'success': NetworkFunction.delete,
+        'failed': Subscription.update_sub_nf_status
+    },
+    AdministrativeState.UNLOCKED.value: {
+        'success': Subscription.update_sub_nf_status,
+        'failed': Subscription.update_sub_nf_status
+    }
+}
diff --git a/components/pm-subscription-handler/pmsh_service/mod/subscription.py b/components/pm-subscription-handler/pmsh_service/mod/subscription.py
index 265d90b8..031609aa 100755
--- a/components/pm-subscription-handler/pmsh_service/mod/subscription.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/subscription.py
@@ -16,10 +16,25 @@
 # SPDX-License-Identifier: Apache-2.0
 # ============LICENSE_END=====================================================
 import re
+from enum import Enum
 
 import mod.pmsh_logging as logger
 from mod import db
 from mod.db_models import SubscriptionModel, NfSubRelationalModel
+from tenacity import retry, retry_if_exception_type, wait_exponential, stop_after_attempt
+
+
+class SubNfState(Enum):
+    PENDING_CREATE = 'PENDING_CREATE'
+    CREATE_FAILED = 'CREATE_FAILED'
+    CREATED = 'CREATED'
+    PENDING_DELETE = 'PENDING_DELETE'
+    DELETE_FAILED = 'DELETE_FAILED'
+
+
+class AdministrativeState(Enum):
+    UNLOCKED = 'UNLOCKED'
+    LOCKED = 'LOCKED'
 
 
 class Subscription:
@@ -42,7 +57,10 @@ class Subscription:
             dict: the Subscription event to be published.
         """
         clean_sub = {k: v for k, v in self.__dict__.items() if k != 'nfFilter'}
-        clean_sub.update({'nfName': xnf_name, 'policyName': f'OP-{self.subscriptionName}'})
+        clean_sub.update({'nfName': xnf_name, 'policyName': f'OP-{self.subscriptionName}',
+                          'changeType': 'DELETE'
+                          if self.administrativeState == AdministrativeState.LOCKED.value
+                          else 'CREATE'})
         return clean_sub
 
     def create(self):
@@ -84,7 +102,8 @@ class Subscription:
                 NfSubRelationalModel.subscription_name == current_sub.subscription_name,
                 NfSubRelationalModel.nf_name == current_nf.nf_name).one_or_none()
             if existing_entry is None:
-                new_nf_sub = NfSubRelationalModel(current_sub.subscription_name, nf.nf_name)
+                new_nf_sub = NfSubRelationalModel(current_sub.subscription_name,
+                                                  nf.nf_name, SubNfState.PENDING_CREATE.value)
                 new_nf_sub.nf = current_nf
                 logger.debug(current_nf)
                 current_sub.nfs.append(new_nf_sub)
@@ -114,6 +133,44 @@ class Subscription:
         """
         return SubscriptionModel.query.all()
 
+    def update_subscription_status(self):
+        """ Updates the status of subscription in subscription table """
+        SubscriptionModel.query.filter(
+            SubscriptionModel.subscription_name == self.subscriptionName). \
+            update({SubscriptionModel.status: self.administrativeState},
+                   synchronize_session='evaluate')
+
+        db.session.commit()
+
+    def delete_subscription(self):
+        """ Deletes a subscription from the database """
+        SubscriptionModel.query.filter(
+            SubscriptionModel.subscription_name == self.subscriptionName). \
+            delete(synchronize_session='evaluate')
+
+        db.session.commit()
+
+    @retry(wait=wait_exponential(multiplier=1, min=30, max=120), stop=stop_after_attempt(3),
+           retry=retry_if_exception_type(Exception))
+    def process_subscription(self, nfs, mr_pub):
+        action = 'Deactivate'
+        sub_nf_state = SubNfState.PENDING_DELETE.value
+        self.update_subscription_status()
+
+        if self.administrativeState == AdministrativeState.UNLOCKED.value:
+            action = 'Activate'
+            sub_nf_state = SubNfState.PENDING_CREATE.value
+
+        try:
+            for nf in nfs:
+                mr_pub.publish_subscription_event_data(self, nf.nf_name)
+                logger.debug(f'Publishing Event to {action} '
+                             f'Sub: {self.subscriptionName} for the nf: {nf.nf_name}')
+                self.add_network_functions_to_subscription(nfs)
+                self.update_sub_nf_status(self.subscriptionName, sub_nf_state, nf.nf_name)
+        except Exception as err:
+            raise Exception(f'Error publishing activation event to MR: {err}')
+
     @staticmethod
     def get_all_nfs_subscription_relations():
         """ Retrieves all network function to subscription relations
@@ -125,6 +182,22 @@ class Subscription:
 
         return nf_per_subscriptions
 
+    @staticmethod
+    def update_sub_nf_status(subscription_name, status, nf_name):
+        """ Updates the status of the subscription for a particular nf
+
+        Args:
+            subscription_name (str): The subscription name
+            nf_name (str): The network function name
+            status (str): Status of the subscription
+        """
+        NfSubRelationalModel.query.filter(
+            NfSubRelationalModel.subscription_name == subscription_name,
+            NfSubRelationalModel.nf_name == nf_name). \
+            update({NfSubRelationalModel.nf_sub_status: status}, synchronize_session='evaluate')
+
+        db.session.commit()
+
 
 class NetworkFunctionFilter:
     def __init__(self, **kwargs):
diff --git a/components/pm-subscription-handler/pmsh_service/pmsh_service.py b/components/pm-subscription-handler/pmsh_service/pmsh_service.py
deleted file mode 100755
index c564a5e3..00000000
--- a/components/pm-subscription-handler/pmsh_service/pmsh_service.py
+++ /dev/null
@@ -1,49 +0,0 @@
-# ============LICENSE_START===================================================
-#  Copyright (C) 2019-2020 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 sys
-import time
-
-import mod.aai_client as aai_client
-import mod.pmsh_logging as logger
-from mod import db, create_app
-from mod.config_handler import ConfigHandler
-from mod.subscription import Subscription
-
-
-def main():
-
-    try:
-        app = create_app()
-        app.app_context().push()
-        db.create_all(app=app)
-
-        config_handler = ConfigHandler()
-        cbs_data = config_handler.get_config()
-        subscription, xnfs = aai_client.get_pmsh_subscription_data(cbs_data)
-        subscription.add_network_functions_to_subscription(xnfs)
-    except Exception as e:
-        logger.debug(f'Failed to Init PMSH: {e}')
-        sys.exit(e)
-
-    while True:
-        logger.debug(Subscription.get_all_nfs_subscription_relations())
-        time.sleep(5)
-
-
-if __name__ == '__main__':
-    main()
diff --git a/components/pm-subscription-handler/pmsh_service/pmsh_service_main.py b/components/pm-subscription-handler/pmsh_service/pmsh_service_main.py
new file mode 100755
index 00000000..ab330320
--- /dev/null
+++ b/components/pm-subscription-handler/pmsh_service/pmsh_service_main.py
@@ -0,0 +1,94 @@
+# ============LICENSE_START===================================================
+#  Copyright (C) 2019-2020 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 sys
+import time
+import threading
+
+import mod.aai_client as aai
+import mod.pmsh_logging as logger
+from mod import db, create_app
+from mod.config_handler import ConfigHandler
+from mod.pmsh_utils import AppConfig
+from mod.subscription import Subscription, AdministrativeState
+
+
+def subscription_processor(config_handler, administrative_state, mr_pub, app):
+    """
+    Checks for changes of administrative state in config and proceeds to process
+    the Subscription if a change has occurred
+
+    Args:
+        config_handler (ConfigHandler): Configuration Handler used to get config
+        administrative_state (str): The administrative state
+        mr_pub (_MrPub): MR publisher
+        app (db): DB application
+    """
+    app.app_context().push()
+    config = config_handler.get_config()
+    sub, nfs = aai.get_pmsh_subscription_data(config)
+    new_administrative_state = config['policy']['subscription']['administrativeState']
+    polling_period = 30.0
+
+    try:
+        if administrative_state == new_administrative_state:
+            logger.debug('Administrative State did not change in the Config')
+        else:
+            sub.process_subscription(nfs, mr_pub)
+
+    except Exception as err:
+        logger.debug(f'Error occurred during the activation/deactivation process {err}')
+
+    threading.Timer(polling_period, subscription_processor,
+                    [config_handler, new_administrative_state, mr_pub, app]).start()
+
+
+def main():
+
+    try:
+        config_handler = ConfigHandler()
+        config = config_handler.get_config()
+        app_conf = AppConfig(**config['config'])
+        app = create_app()
+        app.app_context().push()
+        db.create_all(app=app)
+        sub, nfs = aai.get_pmsh_subscription_data(config)
+        mr_pub = app_conf.get_mr_pub('policy_pm_publisher')
+        mr_sub = app_conf.get_mr_sub('policy_pm_subscriber')
+        initial_start_delay = 5.0
+
+        administrative_state = AdministrativeState.LOCKED.value
+        subscription_in_db = Subscription.get(sub.subscriptionName)
+        if subscription_in_db is not None:
+            administrative_state = subscription_in_db.status
+
+        threading.Timer(initial_start_delay, subscription_processor,
+                        [config_handler, administrative_state, mr_pub, app]).start()
+
+        threading.Timer(20.0, mr_sub.poll_policy_topic, [sub.subscriptionName, app]).start()
+
+    except Exception as e:
+        logger.debug(f'Failed to Init PMSH: {e}')
+        sys.exit(e)
+
+    while True:
+        logger.debug(Subscription.get_all_nfs_subscription_relations())
+        time.sleep(5)
+
+
+if __name__ == '__main__':
+    main()