fix(scaling): min instance count now from right sol006 field and condition fixed...
[osm/POL.git] / osm_policy_module / autoscaling / service.py
index e1f0704..57756b7 100644 (file)
@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+# pylint: disable=no-member
 
 # Copyright 2018 Whitestack, LLC
 # *************************************************************
@@ -31,14 +32,14 @@ from osm_policy_module.common.lcm_client import LcmClient
 from osm_policy_module.common.mon_client import MonClient
 from osm_policy_module.core import database
 from osm_policy_module.core.config import Config
-from osm_policy_module.core.database import ScalingGroup, ScalingAlarm, ScalingPolicy, ScalingCriteria
+from osm_policy_module.core.database import ScalingGroup, ScalingAlarm, ScalingPolicy, ScalingCriteria, \
+    ScalingAlarmRepository, ScalingGroupRepository, ScalingPolicyRepository, ScalingCriteriaRepository
 from osm_policy_module.core.exceptions import VdurNotFound
-from osm_policy_module.utils.vnfd import VnfdUtils
 
 log = logging.getLogger(__name__)
 
 
-class Service:
+class AutoscalingService:
 
     def __init__(self, config: Config, loop=None):
         self.conf = config
@@ -50,223 +51,140 @@ class Service:
         self.lcm_client = LcmClient(config, loop=self.loop)
 
     async def configure_scaling_groups(self, nsr_id: str):
-        log.debug("_configure_scaling_groups: %s", nsr_id)
+        """
+        Configures scaling groups for a network service. Creates records in DB. Creates alarms in MON.
+        :param nsr_id: Network service record id
+        :return:
+        """
+        log.info("Configuring scaling groups for network service with nsr_id: %s",
+                 nsr_id)
         alarms_created = []
         database.db.connect()
-        with database.db.atomic() as tx:
-            try:
-                vnfrs = self.db_client.get_vnfrs(nsr_id)
-                for vnfr in vnfrs:
-                    log.info("Processing vnfr: %s", vnfr)
-                    vnfd = self.db_client.get_vnfd(vnfr['vnfd-id'])
-                    log.info("Looking for vnfd %s", vnfr['vnfd-id'])
-                    if 'scaling-group-descriptor' not in vnfd:
-                        continue
-                    scaling_groups = vnfd['scaling-group-descriptor']
-                    vnf_monitoring_params = vnfd['monitoring-param']
-                    for scaling_group in scaling_groups:
-                        try:
-                            scaling_group_record = ScalingGroup.select().where(
-                                ScalingGroup.nsr_id == nsr_id,
-                                ScalingGroup.vnf_member_index == int(vnfr['member-vnf-index-ref']),
-                                ScalingGroup.name == scaling_group['name']
-                            ).get()
-                            log.info("Found existing scaling group record in DB...")
-                        except ScalingGroup.DoesNotExist:
-                            log.info("Creating scaling group record in DB...")
-                            scaling_group_record = ScalingGroup.create(
-                                nsr_id=nsr_id,
-                                vnf_member_index=vnfr['member-vnf-index-ref'],
-                                name=scaling_group['name'],
-                                content=json.dumps(scaling_group)
-                            )
-                            log.info(
-                                "Created scaling group record in DB : nsr_id=%s, vnf_member_index=%s, name=%s",
-                                scaling_group_record.nsr_id,
-                                scaling_group_record.vnf_member_index,
-                                scaling_group_record.name)
-                        for scaling_policy in scaling_group['scaling-policy']:
-                            if scaling_policy['scaling-type'] != 'automatic':
-                                continue
-                            try:
-                                scaling_policy_record = ScalingPolicy.select().join(ScalingGroup).where(
-                                    ScalingPolicy.name == scaling_policy['name'],
-                                    ScalingGroup.id == scaling_group_record.id
-                                ).get()
-                                log.info("Found existing scaling policy record in DB...")
-                            except ScalingPolicy.DoesNotExist:
-                                log.info("Creating scaling policy record in DB...")
-                                scaling_policy_record = ScalingPolicy.create(
-                                    nsr_id=nsr_id,
-                                    name=scaling_policy['name'],
-                                    cooldown_time=scaling_policy['cooldown-time'],
-                                    scaling_group=scaling_group_record
-                                )
-                                log.info("Created scaling policy record in DB : name=%s, scaling_group.name=%s",
-                                         scaling_policy_record.name,
-                                         scaling_policy_record.scaling_group.name)
-
-                            for scaling_criteria in scaling_policy['scaling-criteria']:
-                                try:
-                                    scaling_criteria_record = ScalingCriteria.select().join(ScalingPolicy).where(
-                                        ScalingPolicy.id == scaling_policy_record.id,
-                                        ScalingCriteria.name == scaling_criteria['name']
-                                    ).get()
-                                    log.info("Found existing scaling criteria record in DB...")
-                                except ScalingCriteria.DoesNotExist:
-                                    log.info("Creating scaling criteria record in DB...")
-                                    scaling_criteria_record = ScalingCriteria.create(
-                                        nsr_id=nsr_id,
-                                        name=scaling_criteria['name'],
-                                        scaling_policy=scaling_policy_record
-                                    )
-                                    log.info(
-                                        "Created scaling criteria record in DB : name=%s, scaling_policy.name=%s",
-                                        scaling_criteria_record.name,
-                                        scaling_criteria_record.scaling_policy.name)
-
-                                vnf_monitoring_param = next(
-                                    filter(
-                                        lambda param: param['id'] == scaling_criteria[
-                                            'vnf-monitoring-param-ref'
-                                        ],
-                                        vnf_monitoring_params)
-                                )
-                                if 'vdu-monitoring-param' in vnf_monitoring_param:
-                                    vdurs = list(
-                                        filter(
-                                            lambda vdur: vdur['vdu-id-ref'] == vnf_monitoring_param
-                                            ['vdu-monitoring-param']
-                                            ['vdu-ref'],
-                                            vnfr['vdur']
-                                        )
+        try:
+            with database.db.atomic() as tx:
+                try:
+                    vnfrs = self.db_client.get_vnfrs(nsr_id)
+                    for vnfr in vnfrs:
+                        log.debug("Processing vnfr: %s", vnfr)
+                        vnfd = self.db_client.get_vnfd(vnfr['vnfd-id'])
+                        # TODO: Change for multiple DF support
+                        df = vnfd.get('df', [{}])[0]
+                        if 'scaling-aspect' not in df:
+                            log.debug("No scaling aspect present in vnfd")
+                            continue
+                        # TODO: Change for multiple instantiation levels support
+                        scaling_aspects = df['scaling-aspect']
+                        all_vnfd_monitoring_params = self._get_all_vnfd_monitoring_params(vnfd)
+                        for scaling_aspect in scaling_aspects:
+                            scaling_group_record = self._get_or_create_scaling_group(nsr_id,
+                                                                                     vnfr['member-vnf-index-ref'],
+                                                                                     scaling_aspect)
+                            vdurs = self._get_monitored_vdurs(scaling_aspect, vnfr['vdur'])
+                            for scaling_policy in scaling_aspect.get('scaling-policy', ()):
+                                if scaling_policy['scaling-type'] != 'automatic':
+                                    continue
+                                scaling_policy_record = self._get_or_create_scaling_policy(nsr_id,
+                                                                                           scaling_policy,
+                                                                                           scaling_group_record)
+
+                                for scaling_criteria in scaling_policy['scaling-criteria']:
+                                    scaling_criteria_record = self._get_or_create_scaling_criteria(
+                                        nsr_id,
+                                        scaling_criteria,
+                                        scaling_policy_record
                                     )
-                                elif 'vdu-metric' in vnf_monitoring_param:
-                                    vdurs = list(
-                                        filter(
-                                            lambda vdur: vdur['vdu-id-ref'] == vnf_monitoring_param
-                                            ['vdu-metric']
-                                            ['vdu-ref'],
-                                            vnfr['vdur']
+                                    monitoring_param_ref = scaling_criteria.get('vnf-monitoring-param-ref')
+                                    vnf_monitoring_param = all_vnfd_monitoring_params[monitoring_param_ref]
+
+                                    for vdur in vdurs:
+                                        vdu_id = vdur['vdu-id-ref']
+                                        log.debug("Creating alarm for vdur %s ", vdur)
+                                        try:
+                                            ScalingAlarmRepository.get(ScalingAlarm.vdu_name == vdur['name'],
+                                                                       ScalingCriteria.name == scaling_criteria['name'],
+                                                                       ScalingPolicy.name == scaling_policy['name'],
+                                                                       ScalingGroup.nsr_id == nsr_id,
+                                                                       join_classes=[ScalingCriteria,
+                                                                                     ScalingPolicy,
+                                                                                     ScalingGroup])
+                                            log.debug("vdu %s already has an alarm configured", vdur['name'])
+                                            continue
+                                        except ScalingAlarm.DoesNotExist:
+                                            pass
+                                        metric_name = self._get_metric_name(vnf_monitoring_param)
+
+                                        db_nsr = self.db_client.get_nsr(nsr_id)
+                                        nb_scale_op = 0
+                                        if db_nsr["_admin"].get("scaling-group"):
+                                            db_nsr_admin = db_nsr["_admin"]["scaling-group"]
+                                            for admin_scale_index, admin_scale_info in enumerate(db_nsr_admin):
+                                                if admin_scale_info["name"] == scaling_aspect["name"]:
+                                                    nb_scale_op = admin_scale_info.get("nb-scale-op", 0)
+                                                    break
+                                        min_instance_count = 1
+                                        for vdu_profile in df.get('vdu-profile', ()):
+                                            if vdu_profile.get('id') == vdu_id:
+                                                min_instance_count = int(vdu_profile.get('min-number-of-instances ', 1))
+                                                break
+                                        if nb_scale_op >= min_instance_count:
+                                            alarm_uuid = await self.mon_client.create_alarm(
+                                                metric_name=metric_name,
+                                                ns_id=nsr_id,
+                                                vdu_name=vdur['name'],
+                                                vnf_member_index=vnfr['member-vnf-index-ref'],
+                                                threshold=scaling_criteria['scale-in-threshold'],
+                                                operation=scaling_criteria['scale-in-relational-operation']
+                                            )
+                                            alarm = ScalingAlarmRepository.create(
+                                                alarm_uuid=alarm_uuid,
+                                                action='scale_in',
+                                                vnf_member_index=vnfr['member-vnf-index-ref'],
+                                                vdu_name=vdur['name'],
+                                                scaling_criteria=scaling_criteria_record
+                                            )
+                                            alarms_created.append(alarm)
+                                        alarm_uuid = await self.mon_client.create_alarm(
+                                            metric_name=metric_name,
+                                            ns_id=nsr_id,
+                                            vdu_name=vdur['name'],
+                                            vnf_member_index=vnfr['member-vnf-index-ref'],
+                                            threshold=scaling_criteria['scale-out-threshold'],
+                                            operation=scaling_criteria['scale-out-relational-operation']
                                         )
-                                    )
-                                elif 'vnf-metric' in vnf_monitoring_param:
-                                    vdu = VnfdUtils.get_mgmt_vdu(vnfd)
-                                    vdurs = list(
-                                        filter(
-                                            lambda vdur: vdur['vdu-id-ref'] == vdu['id'],
-                                            vnfr['vdur']
+                                        alarm = ScalingAlarmRepository.create(
+                                            alarm_uuid=alarm_uuid,
+                                            action='scale_out',
+                                            vnf_member_index=vnfr['member-vnf-index-ref'],
+                                            vdu_name=vdur['name'],
+                                            scaling_criteria=scaling_criteria_record
                                         )
-                                    )
-                                else:
-                                    log.warning(
-                                        "Scaling criteria is referring to a vnf-monitoring-param that does not "
-                                        "contain a reference to a vdu or vnf metric.")
-                                    continue
-                                for vdur in vdurs:
-                                    log.info("Creating alarm for vdur %s ", vdur)
-                                    try:
-                                        (ScalingAlarm.select()
-                                         .join(ScalingCriteria)
-                                         .join(ScalingPolicy)
-                                         .join(ScalingGroup)
-                                         .where(
-                                            ScalingAlarm.vdu_name == vdur['name'],
-                                            ScalingCriteria.name == scaling_criteria['name'],
-                                            ScalingPolicy.name == scaling_policy['name'],
-                                            ScalingGroup.nsr_id == nsr_id
-                                        ).get())
-                                        log.debug("vdu %s already has an alarm configured", vdur['name'])
-                                        continue
-                                    except ScalingAlarm.DoesNotExist:
-                                        pass
-                                    alarm_uuid = await self.mon_client.create_alarm(
-                                        metric_name=vnf_monitoring_param['id'],
-                                        ns_id=nsr_id,
-                                        vdu_name=vdur['name'],
-                                        vnf_member_index=vnfr['member-vnf-index-ref'],
-                                        threshold=scaling_criteria['scale-in-threshold'],
-                                        operation=scaling_criteria['scale-in-relational-operation'],
-                                        statistic=vnf_monitoring_param['aggregation-type']
-                                    )
-                                    alarm = ScalingAlarm.create(
-                                        alarm_uuid=alarm_uuid,
-                                        action='scale_in',
-                                        vnf_member_index=int(vnfr['member-vnf-index-ref']),
-                                        vdu_name=vdur['name'],
-                                        scaling_criteria=scaling_criteria_record
-                                    )
-                                    alarms_created.append(alarm)
-                                    alarm_uuid = await self.mon_client.create_alarm(
-                                        metric_name=vnf_monitoring_param['id'],
-                                        ns_id=nsr_id,
-                                        vdu_name=vdur['name'],
-                                        vnf_member_index=vnfr['member-vnf-index-ref'],
-                                        threshold=scaling_criteria['scale-out-threshold'],
-                                        operation=scaling_criteria['scale-out-relational-operation'],
-                                        statistic=vnf_monitoring_param['aggregation-type']
-                                    )
-                                    alarm = ScalingAlarm.create(
-                                        alarm_uuid=alarm_uuid,
-                                        action='scale_out',
-                                        vnf_member_index=int(vnfr['member-vnf-index-ref']),
-                                        vdu_name=vdur['name'],
-                                        scaling_criteria=scaling_criteria_record
-                                    )
-                                    alarms_created.append(alarm)
-
-            except Exception as e:
-                log.exception("Error configuring scaling groups:")
-                tx.rollback()
-                if len(alarms_created) > 0:
-                    log.info("Cleaning alarm resources in MON")
-                    for alarm in alarms_created:
-                        await self.mon_client.delete_alarm(alarm.scaling_criteria.scaling_policy.scaling_group.nsr_id,
-                                                           alarm.vnf_member_index,
-                                                           alarm.vdu_name,
-                                                           alarm.alarm_uuid)
-                raise e
-        database.db.close()
+                                        alarms_created.append(alarm)
 
-    async def delete_scaling_groups(self, nsr_id: str):
-        database.db.connect()
-        with database.db.atomic() as tx:
-            try:
-                for scaling_group in ScalingGroup.select().where(ScalingGroup.nsr_id == nsr_id):
-                    for scaling_policy in scaling_group.scaling_policies:
-                        for scaling_criteria in scaling_policy.scaling_criterias:
-                            for alarm in scaling_criteria.scaling_alarms:
-                                try:
-                                    await self.mon_client.delete_alarm(
-                                        alarm.scaling_criteria.scaling_policy.scaling_group.nsr_id,
-                                        alarm.vnf_member_index,
-                                        alarm.vdu_name,
-                                        alarm.alarm_uuid)
-                                except ValueError:
-                                    log.exception("Error deleting alarm in MON %s", alarm.alarm_uuid)
-                                alarm.delete_instance()
-                            scaling_criteria.delete_instance()
-                        scaling_policy.delete_instance()
-                    scaling_group.delete_instance()
-
-            except Exception as e:
-                log.exception("Error deleting scaling groups and alarms:")
-                tx.rollback()
-                raise e
-        database.db.close()
+                except Exception as e:
+                    log.exception("Error configuring scaling groups:")
+                    tx.rollback()
+                    if len(alarms_created) > 0:
+                        log.info("Cleaning alarm resources in MON")
+                        for alarm in alarms_created:
+                            await self.mon_client.delete_alarm(
+                                alarm.scaling_criteria.scaling_policy.scaling_group.nsr_id,
+                                alarm.vnf_member_index,
+                                alarm.vdu_name,
+                                alarm.alarm_uuid)
+                    raise e
+        finally:
+            database.db.close()
 
-    async def delete_orphaned_alarms(self, nsr_id):
+    async def delete_scaling_groups(self, nsr_id: str):
+        log.debug("Deleting scaling groups for network service %s", nsr_id)
         database.db.connect()
-        with database.db.atomic() as tx:
-            try:
-                for scaling_group in ScalingGroup.select().where(ScalingGroup.nsr_id == nsr_id):
-                    for scaling_policy in scaling_group.scaling_policies:
-                        for scaling_criteria in scaling_policy.scaling_criterias:
-                            for alarm in scaling_criteria.scaling_alarms:
-                                try:
-                                    self.db_client.get_vdur(nsr_id, alarm.vnf_member_index, alarm.vdu_name)
-                                except VdurNotFound:
-                                    log.info("Deleting orphaned alarm %s", alarm.alarm_uuid)
+        try:
+            with database.db.atomic() as tx:
+                try:
+                    for scaling_group in ScalingGroupRepository.list(ScalingGroup.nsr_id == nsr_id):
+                        for scaling_policy in scaling_group.scaling_policies:
+                            for scaling_criteria in scaling_policy.scaling_criterias:
+                                for alarm in scaling_criteria.scaling_alarms:
                                     try:
                                         await self.mon_client.delete_alarm(
                                             alarm.scaling_criteria.scaling_policy.scaling_group.nsr_id,
@@ -276,36 +194,209 @@ class Service:
                                     except ValueError:
                                         log.exception("Error deleting alarm in MON %s", alarm.alarm_uuid)
                                     alarm.delete_instance()
+                                scaling_criteria.delete_instance()
+                            scaling_policy.delete_instance()
+                        scaling_group.delete_instance()
 
-            except Exception as e:
-                log.exception("Error deleting orphaned alarms:")
-                tx.rollback()
-                raise e
-        database.db.close()
+                except Exception as e:
+                    log.exception("Error deleting scaling groups and alarms:")
+                    tx.rollback()
+                    raise e
+        finally:
+            database.db.close()
 
-    async def scale(self, alarm):
+    async def delete_orphaned_alarms(self, nsr_id):
+        log.info("Deleting orphaned scaling alarms for network service %s", nsr_id)
         database.db.connect()
-        with database.db.atomic():
-            delta = datetime.datetime.now() - alarm.scaling_criteria.scaling_policy.last_scale
-            if delta.total_seconds() > alarm.scaling_criteria.scaling_policy.cooldown_time:
-                log.info("Sending scaling action message for ns: %s",
-                         alarm.scaling_criteria.scaling_policy.scaling_group.nsr_id)
-                await self.lcm_client.scale(alarm.scaling_criteria.scaling_policy.scaling_group.nsr_id,
-                                            alarm.scaling_criteria.scaling_policy.scaling_group.name,
-                                            alarm.vnf_member_index,
-                                            alarm.action)
-                alarm.scaling_criteria.scaling_policy.last_scale = datetime.datetime.now()
-                alarm.scaling_criteria.scaling_policy.save()
-            else:
-                log.info("Time between last scale and now is less than cooldown time. Skipping.")
-        database.db.close()
-
-    def get_alarm(self, alarm_uuid: str):
+        try:
+            with database.db.atomic() as tx:
+                try:
+                    for scaling_group in ScalingGroupRepository.list(ScalingGroup.nsr_id == nsr_id):
+                        for scaling_policy in scaling_group.scaling_policies:
+                            for scaling_criteria in scaling_policy.scaling_criterias:
+                                for alarm in scaling_criteria.scaling_alarms:
+                                    try:
+                                        self.db_client.get_vdur(nsr_id, alarm.vnf_member_index, alarm.vdu_name)
+                                    except VdurNotFound:
+                                        log.debug("Deleting orphaned scaling alarm %s", alarm.alarm_uuid)
+                                        try:
+                                            await self.mon_client.delete_alarm(
+                                                alarm.scaling_criteria.scaling_policy.scaling_group.nsr_id,
+                                                alarm.vnf_member_index,
+                                                alarm.vdu_name,
+                                                alarm.alarm_uuid)
+                                        except ValueError:
+                                            log.exception("Error deleting alarm in MON %s", alarm.alarm_uuid)
+                                        alarm.delete_instance()
+
+                except Exception as e:
+                    log.exception("Error deleting orphaned alarms:")
+                    tx.rollback()
+                    raise e
+        finally:
+            database.db.close()
+
+    async def handle_alarm(self, alarm_uuid: str, status: str):
+        await self.update_alarm_status(alarm_uuid, status)
+        await self.evaluate_policy(alarm_uuid)
+
+    async def update_alarm_status(self, alarm_uuid: str, status: str):
         database.db.connect()
-        with database.db.atomic():
-            alarm = ScalingAlarm.select().where(ScalingAlarm.alarm_uuid == alarm_uuid).get()
-        database.db.close()
-        return alarm
+        try:
+            with database.db.atomic():
+                alarm = ScalingAlarmRepository.get(ScalingAlarm.alarm_uuid == alarm_uuid)
+                alarm.last_status = status
+                alarm.save()
+        except ScalingAlarm.DoesNotExist:
+            log.debug("There is no autoscaling action configured for alarm %s.", alarm_uuid)
+        finally:
+            database.db.close()
+
+    async def evaluate_policy(self, alarm_uuid):
+        database.db.connect()
+        try:
+            with database.db.atomic():
+                alarm = ScalingAlarmRepository.get(ScalingAlarm.alarm_uuid == alarm_uuid)
+                vnf_member_index = alarm.vnf_member_index
+                action = alarm.action
+                scaling_policy = alarm.scaling_criteria.scaling_policy
+                if not scaling_policy.enabled:
+                    return
+                if action == 'scale_in':
+                    operation = scaling_policy.scale_in_operation
+                elif action == 'scale_out':
+                    operation = scaling_policy.scale_out_operation
+                else:
+                    raise Exception('Unknown alarm action {}'.format(alarm.action))
+                alarms = ScalingAlarmRepository.list(ScalingAlarm.scaling_criteria == alarm.scaling_criteria,
+                                                     ScalingAlarm.action == alarm.action,
+                                                     ScalingAlarm.vnf_member_index == vnf_member_index,
+                                                     ScalingAlarm.vdu_name == alarm.vdu_name)
+                statuses = []
+                for alarm in alarms:
+                    statuses.append(alarm.last_status)
+                if (operation == 'AND' and set(statuses) == {'alarm'}) or (operation == 'OR' and 'alarm' in statuses):
+                    delta = datetime.datetime.now() - scaling_policy.last_scale
+                    if delta.total_seconds() > scaling_policy.cooldown_time:
+                        log.info("Sending %s action message for ns: %s",
+                                 alarm.action,
+                                 scaling_policy.scaling_group.nsr_id)
+                        await self.lcm_client.scale(scaling_policy.scaling_group.nsr_id,
+                                                    scaling_policy.scaling_group.name,
+                                                    vnf_member_index,
+                                                    action)
+                        scaling_policy.last_scale = datetime.datetime.now()
+                        scaling_policy.save()
+
+        except ScalingAlarm.DoesNotExist:
+            log.debug("There is no autoscaling action configured for alarm %s.", alarm_uuid)
+        finally:
+            database.db.close()
+
+    def _get_all_vnfd_monitoring_params(self, vnfd):
+        all_monitoring_params = {}
+        for ivld in vnfd.get("int-virtual-link-desc", ()):
+            for mp in ivld.get("monitoring-parameters", ()):
+                all_monitoring_params[mp.get("id")] = mp
+
+        for vdu in vnfd.get("vdu", ()):
+            for mp in vdu.get("monitoring-parameter", ()):
+                all_monitoring_params[mp.get("id")] = mp
+
+        for df in vnfd.get("df", ()):
+            for mp in df.get("monitoring-parameter", ()):
+                all_monitoring_params[mp.get("id")] = mp
+
+        return all_monitoring_params
+
+    def _get_or_create_scaling_group(self, nsr_id: str, vnf_member_index: str, scaling_aspect: dict):
+        try:
+            scaling_group_record = ScalingGroupRepository.get(
+                ScalingGroup.nsr_id == nsr_id,
+                ScalingGroup.vnf_member_index == vnf_member_index,
+                ScalingGroup.name == scaling_aspect['name']
+            )
+            log.debug("Found existing scaling group record in DB...")
+        except ScalingGroup.DoesNotExist:
+            log.debug("Creating scaling group record in DB...")
+            scaling_group_record = ScalingGroupRepository.create(
+                nsr_id=nsr_id,
+                vnf_member_index=vnf_member_index,
+                name=scaling_aspect['name'],
+                content=json.dumps(scaling_aspect)
+            )
+            log.debug(
+                "Created scaling group record in DB : nsr_id=%s, vnf_member_index=%s, name=%s",
+                scaling_group_record.nsr_id,
+                scaling_group_record.vnf_member_index,
+                scaling_group_record.name)
+        return scaling_group_record
+
+    def _get_or_create_scaling_policy(self, nsr_id: str, scaling_policy: dict, scaling_group_record: ScalingGroup):
+        try:
+            scaling_policy_record = ScalingPolicyRepository.get(
+                ScalingPolicy.name == scaling_policy['name'],
+                ScalingGroup.id == scaling_group_record.id,
+                join_classes=[ScalingGroup]
+            )
+            log.debug("Found existing scaling policy record in DB...")
+        except ScalingPolicy.DoesNotExist:
+            log.debug("Creating scaling policy record in DB...")
+            scaling_policy_record = ScalingPolicyRepository.create(
+                nsr_id=nsr_id,
+                name=scaling_policy['name'],
+                cooldown_time=scaling_policy['cooldown-time'],
+                scaling_group=scaling_group_record,
+            )
+            if 'scale-in-operation-type' in scaling_policy:
+                scaling_policy_record.scale_in_operation = scaling_policy['scale-in-operation-type']
+            if 'scale-out-operation-type' in scaling_policy:
+                scaling_policy_record.scale_out_operation = scaling_policy['scale-out-operation-type']
+            if 'enabled' in scaling_policy:
+                scaling_policy_record.enabled = scaling_policy['enabled']
+            scaling_policy_record.save()
+            log.debug("Created scaling policy record in DB : name=%s, scaling_group.name=%s",
+                      scaling_policy_record.name,
+                      scaling_policy_record.scaling_group.name)
+        return scaling_policy_record
+
+    def _get_or_create_scaling_criteria(self, nsr_id: str, scaling_criteria: dict,
+                                        scaling_policy_record: ScalingPolicy):
+        try:
+            scaling_criteria_record = ScalingCriteriaRepository.get(
+                ScalingPolicy.id == scaling_policy_record.id,
+                ScalingCriteria.name == scaling_criteria['name'],
+                join_classes=[ScalingPolicy]
+            )
+            log.debug("Found existing scaling criteria record in DB...")
+        except ScalingCriteria.DoesNotExist:
+            log.debug("Creating scaling criteria record in DB...")
+            scaling_criteria_record = ScalingCriteriaRepository.create(
+                nsr_id=nsr_id,
+                name=scaling_criteria['name'],
+                scaling_policy=scaling_policy_record
+            )
+            log.debug(
+                "Created scaling criteria record in DB : name=%s, scaling_policy.name=%s",
+                scaling_criteria_record.name,
+                scaling_criteria_record.scaling_policy.name)
+        return scaling_criteria_record
+
+    def _get_monitored_vdurs(self, scaling_aspect: dict, vdurs):
+        all_monitored_vdus = set()
+        for delta in scaling_aspect.get('aspect-delta-details', {}).get('deltas', ()):
+            for vdu_delta in delta.get('vdu-delta', ()):
+                all_monitored_vdus.add(vdu_delta.get('id'))
+
+        monitored_vdurs = list(filter(lambda vdur: vdur['vdu-id-ref'] in all_monitored_vdus, vdurs))
+
+        if not monitored_vdurs:
+            log.warning(
+                "Scaling criteria is referring to a vnf-monitoring-param that does not "
+                "contain a reference to a vdu or vnf metric.")
+        return monitored_vdurs
 
-    def get_nslcmop(self, nslcmop_id):
-        return self.db_client.get_nslcmop(nslcmop_id)
+    def _get_metric_name(self, vnf_monitoring_param: dict):
+        if 'performance-metric' in vnf_monitoring_param:
+            return vnf_monitoring_param['performance-metric']
+        raise ValueError('No metric name found for vnf_monitoring_param %s' % vnf_monitoring_param['id'])