+import json
+import logging
+
+from kafka import KafkaConsumer
+from osm_policy_module.core.config import Config
+from osm_policy_module.common.lcm_client import LcmClient
+
+from osm_policy_module.common.alarm_config import AlarmConfig
+from osm_policy_module.common.mon_client import MonClient
+from osm_policy_module.core.database import ScalingRecord, ScalingAlarm
+
+log = logging.getLogger(__name__)
+
+
+class PolicyModuleAgent:
+ def run(self):
+ cfg = Config.instance()
+ # Initialize servers
+ kafka_server = '{}:{}'.format(cfg.get('policy_module', 'kafka_server_host'),
+ cfg.get('policy_module', 'kafka_server_port'))
+
+ # Initialize Kafka consumer
+ log.info("Connecting to Kafka server at %s", kafka_server)
+ consumer = KafkaConsumer(bootstrap_servers=kafka_server,
+ key_deserializer=bytes.decode,
+ value_deserializer=bytes.decode,
+ group_id="policy-module-agent")
+ consumer.subscribe(['lcm_pm', 'alarm_response'])
+
+ for message in consumer:
+ log.info("Message arrived: %s", message)
+ log.info("Message key: %s", message.key)
+ try:
+ if message.key == 'configure_scaling':
+ content = json.loads(message.value)
+ log.info("Creating scaling record in DB")
+ # TODO: Use transactions: http://docs.peewee-orm.com/en/latest/peewee/transactions.html
+ scaling_record = ScalingRecord.create(
+ nsr_id=content['ns_id'],
+ name=content['scaling_group_descriptor']['name'],
+ content=json.dumps(content)
+ )
+ log.info("Created scaling record in DB : nsr_id=%s, name=%s, content=%s",
+ scaling_record.nsr_id,
+ scaling_record.name,
+ scaling_record.content)
+ alarm_configs = self._get_alarm_configs(content)
+ for config in alarm_configs:
+ mon_client = MonClient()
+ log.info("Creating alarm record in DB")
+ alarm_uuid = mon_client.create_alarm(
+ metric_name=config.metric_name,
+ resource_uuid=config.resource_uuid,
+ vim_uuid=config.vim_uuid,
+ threshold=config.threshold,
+ operation=config.operation,
+ statistic=config.statistic
+ )
+ ScalingAlarm.create(
+ alarm_id=alarm_uuid,
+ action=config.action,
+ scaling_record=scaling_record
+ )
+ if message.key == 'notify_alarm':
+ content = json.loads(message.value)
+ alarm_id = content['notify_details']['alarm_uuid']
+ alarm = ScalingAlarm.select().where(ScalingAlarm.alarm_id == alarm_id).get()
+ if alarm:
+ lcm_client = LcmClient()
+ log.info("Sending scaling action message: %s", json.dumps(alarm))
+ lcm_client.scale(alarm.scaling_record.nsr_id, alarm.scaling_record.name, alarm.action)
+ except Exception:
+ log.exception("Error consuming message: ")
+
+ def _get_alarm_configs(self, message_content):
+ scaling_criterias = message_content['scaling_group_descriptor']['scaling_policy']['scaling_criteria']
+ alarm_configs = []
+ for criteria in scaling_criterias:
+ metric_name = ''
+ scale_out_threshold = criteria['scale_out_threshold']
+ scale_in_threshold = criteria['scale_in_threshold']
+ scale_out_operation = criteria['scale_out_relational_operation']
+ scale_in_operation = criteria['scale_in_relational_operation']
+ statistic = criteria['monitoring_param']['aggregation_type']
+ vim_uuid = ''
+ resource_uuid = ''
+ if 'vdu_monitoring_param' in criteria['monitoring_param']:
+ vim_uuid = criteria['monitoring_param']['vdu_monitoring_param']['vim_uuid']
+ resource_uuid = criteria['monitoring_param']['vdu_monitoring_param']['resource_id']
+ metric_name = criteria['monitoring_param']['vdu_monitoring_param']['name']
+ if 'vnf_metric' in criteria['monitoring_param']:
+ # TODO vnf_metric
+ continue
+ if 'vdu_metric' in criteria['monitoring_param']:
+ # TODO vdu_metric
+ continue
+ scale_out_alarm_config = AlarmConfig(metric_name,
+ resource_uuid,
+ vim_uuid,
+ scale_out_threshold,
+ scale_out_operation,
+ statistic,
+ 'scale_out')
+ scale_in_alarm_config = AlarmConfig(metric_name,
+ resource_uuid,
+ vim_uuid,
+ scale_in_threshold,
+ scale_in_operation,
+ statistic,
+ 'scale_in')
+ alarm_configs.append(scale_in_alarm_config)
+ alarm_configs.append(scale_out_alarm_config)
+ return alarm_configs