--- /dev/null
+# Copyright 2020 K Sai Kiran (Tata Elxsi)
+#
+# 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.
+
+__author__ = "K Sai Kiran <saikiran.k@tataelxsi.co.in>"
+__date__ = "$28-Apr-2020 23:59:59$"
+
+import asyncio
+import aiohttp
+from http import HTTPStatus
+import json
+import logging
+import time
+from uuid import uuid4
+
+
+class NotificationException(Exception):
+ """
+ Notification Exception
+ """
+
+ def __init__(self, message: str, http_code: int = HTTPStatus.BAD_REQUEST) -> None:
+ """
+ Constructor of notification exception
+ :param message: String text containing exception details.
+ :param http_code: HTTP status code of exception.
+ """
+ self.http_code = http_code
+ Exception.__init__(self, message)
+
+
+class NotificationBase:
+
+ response_models = None
+ # Common HTTP payload header for all notifications.
+ payload_header = {
+ "Content-Type": "application/json",
+ "Accept": "application/json"
+ }
+
+ def __init__(self, db) -> None:
+ """
+ Constructor of NotificationBase class.
+ :param db: Database handler.
+ """
+ self.db = db
+ self.logger = logging.getLogger("nbi.notifications")
+ self.subscriber_collection = None
+
+ def get_models(self) -> dict:
+ """
+ Returns the SOL005 model of notification class
+ :param None
+ :return: dict of SOL005 data model
+ """
+ return NotificationBase.response_models
+
+ def get_subscribers(self, **kwargs) -> NotificationException:
+ """
+ Method should be implemented by all notification subclasses
+ :param kwargs: any keyword arguments needed for db query.
+ :return: List of subscribers
+ """
+ raise NotificationException("Method get_subscribers() is not implemented", http_code=HTTPStatus.NOT_IMPLEMENTED)
+
+ @staticmethod
+ def _get_basic_auth(username: str, password: str) -> tuple:
+ return aiohttp.BasicAuth(username, password)
+
+ def _decrypt_password(self, hashed: str, salt: str, schema_version: str = "1.1") -> str:
+ return self.db.decrypt(hashed, schema_version, salt=salt)
+
+ def get_payload(self, meta_notification: dict) -> dict:
+ """
+ Generates SOL005 compliant payload structure and returns them in dictionary.
+ :param meta_notification: notification meta data which needs to be formatted as SOL005 compliant
+ :return: A dictionary which is SOL005 compliant.
+ """
+ model_name = meta_notification["notificationType"]
+ response_models = self.get_models()
+ if not response_models or not response_models.get(model_name):
+ raise NotificationException("Response model {} is not defined.".format(model_name),
+ HTTPStatus.NOT_IMPLEMENTED)
+ model_keys = response_models[model_name]
+ payload = dict.fromkeys(model_keys, "N/A")
+ notification_keys = set(meta_notification.keys())
+ for model_key in model_keys.intersection(notification_keys):
+ payload[model_key] = meta_notification[model_key]
+ self.logger.debug("Payload generated for subscriber: {} for {}".format(payload["subscriptionId"],
+ payload["notificationType"]))
+ return payload
+
+ async def send_notifications(self, subscribers: list, loop: asyncio.AbstractEventLoop = None):
+ """
+ Generate tasks for all notification for an event.
+ :param subscribers: A list of subscribers who want to be notified for event.
+ :param loop: Event loop object.
+ """
+ notifications = []
+ for subscriber in subscribers:
+ # TODO add support for AuthType OAuth and TLS after support is added in subscription.
+ if subscriber["authentication"]["authType"] != "basic":
+ self.logger.debug("Subscriber {} can not be notified {} notification auth type is not implemented"
+ .format(subscriber["subscriptionId"],
+ subscriber["authentication"]["authType"]))
+ continue
+ salt = subscriber["subscriptionId"]
+ hashed_password = subscriber["authentication"]["paramsBasic"]["password"]
+ password = self._decrypt_password(hashed_password, salt)
+ auth_basic = self._get_basic_auth(subscriber["authentication"]["paramsBasic"]["userName"], password)
+ notifications.append({
+ "headers": self.payload_header,
+ "payload": self.get_payload(subscriber),
+ "auth_basic": auth_basic,
+ "CallbackUri": subscriber["CallbackUri"]
+ })
+ tasks = []
+ async with aiohttp.ClientSession(loop=loop) as session:
+ for notification in notifications:
+ tasks.append(asyncio.ensure_future(self.send_notification(session, notification), loop=loop))
+ await asyncio.gather(*tasks, loop=loop)
+
+ async def send_notification(self, session: aiohttp.ClientSession, notification: dict,
+ loop: asyncio.AbstractEventLoop = None, retry_count: int = 5, timeout: float = 5.0):
+ """
+ Performs HTTP Post request to notify subscriber. In case if for any reason notification is not sent successfully
+ after maximum number of reties, then notification is dropped.
+ :param session: An aiohttp client session object to maintain http session.
+ :param notification: A dictionary containing all necessary data to make POST request.
+ :param loop: Event loop object.
+ :param retry_count: An integer specifying the maximum number of reties for a notification.
+ :param timeout: A float representing client timeout of each HTTP request.
+ """
+ backoff_delay = 1
+ while retry_count > 0:
+ try:
+ async with session.post(url=notification["CallbackUri"], headers=notification["headers"],
+ auth=notification["auth_basic"], data=json.dumps(notification["payload"]),
+ timeout=timeout) as resp:
+ # self.logger.debug("Notification response: {}".format(resp.status))
+ if resp.status == HTTPStatus.NO_CONTENT:
+ self.logger.debug("Notification sent successfully to subscriber {}"
+ .format(notification["payload"]["subscriptionId"]))
+ else:
+ error_text = "Erroneous response code: {}, ".format(resp.status)
+ error_text += await resp.text()
+ raise NotificationException(error_text)
+ return True
+ except Exception as e:
+ error_text = type(e).__name__ + ": " + str(e)
+ self.logger.debug("Unable while sending notification to subscriber {}. Details: {}"
+ .format(notification["payload"]["subscriptionId"], error_text))
+ error_detail = {
+ "error": type(e).__name__,
+ "error_text": str(e),
+ "timestamp": time.time()
+ }
+ if "error_details" in notification["payload"].keys():
+ notification["payload"]["error_details"].append(error_detail)
+ else:
+ notification["payload"]["error_details"] = [error_detail]
+ retry_count -= 1
+ backoff_delay *= 2
+ self.logger.debug("Retry Notification for subscriber: {} after backoff delay: {} seconds."
+ .format(notification["payload"]["subscriptionId"], backoff_delay))
+ await asyncio.sleep(backoff_delay, loop=loop)
+ # Dropping notification
+ self.logger.debug("Notification {} sent failed to subscriber:{}."
+ .format(notification["payload"]["notificationType"],
+ notification["payload"]["subscriptionId"]))
+ return False
+
+
+class NsLcmNotification(NotificationBase):
+
+ # SOL005 response model for nslcm notifications
+ response_models = {
+ "NsLcmOperationOccurrenceNotification": {"id", "nsInstanceId", "nsLcmOpOccId", "operation",
+ "notificationType", "subscriptionId", "timestamp",
+ "notificationStatus", "operationState", "isAutomaticInvocation",
+ "affectedVnf", "affectedVl", "affectedVnffg", "affectedNs",
+ "affectedSap", "error", "_links"},
+
+ "NsIdentifierCreationNotification": {"notificationType", "subscriptionId", "timestamp",
+ "nsInstanceId", "_links"},
+
+ "NsIdentifierDeletionNotification": {"notificationType", "subscriptionId", "timestamp",
+ "nsInstanceId", "_links"},
+
+ "NsChangeNotification": {"nsInstanceId", "nsComponentType", "nsComponentId",
+ "lcmOpOccIdImpactngNsComponent", "lcmOpNameImpactingNsComponent",
+ "lcmOpOccStatusImpactingNsComponent", "notificationType", "subscriptionId",
+ "timeStamp", "error", "_links"}
+ }
+
+ def __init__(self, db) -> None:
+ """
+ Constructor of NotificationBase class.
+ :param db: Database handler.
+ """
+ super().__init__(db)
+ self.subscriber_collection = "mapped_subscriptions"
+
+ def get_models(self) -> dict:
+ """
+ Returns the SOL005 model of notification class
+ :param None
+ :return: dict of SOL005 data model
+ """
+ return NsLcmNotification.response_models
+
+ @staticmethod
+ def _format_nslcm_subscribers(subscribers: list, event_details: dict) -> list:
+ """
+ Formats the raw event details from kakfa message and subscriber details.
+ :param subscribers: A list of subscribers whom the event needs to be notified.
+ :param event_details: A dict containing all meta data of event.
+ :return:
+ """
+ notification_id = str(uuid4())
+ event_timestamp = event_details["params"]["startTime"]
+ resource_links = event_details["params"]["links"]
+ event_operation = event_details["command"]
+ for key in ["_admin", "_id", "id", "links"]:
+ event_details["params"].pop(key, None)
+ for subscriber in subscribers:
+ subscriber["id"] = notification_id
+ subscriber["timestamp"] = event_timestamp
+ subscriber["_links"] = resource_links
+ subscriber["subscriptionId"] = subscriber["reference"]
+ subscriber["operation"] = event_operation
+ del subscriber["reference"]
+ del subscriber["_id"]
+ subscriber.update(event_details["params"])
+ return subscribers
+
+ def get_subscribers(self, nsd_id: str, ns_instance_id: str, command: str, op_state: str,
+ event_details: dict) -> list:
+ """
+ Queries database and returns list of subscribers.
+ :param nsd_id: NSD id of an NS whose lifecycle has changed. (scaled, terminated. etc)
+ :param ns_instance_id: NS instance id an NS whose lifecycle has changed.
+ :param command: the command for event.
+ :param op_state: the operation state of NS.
+ :param event_details: dict containing raw data of event occured.
+ :return: List of interested subscribers for occurred event.
+ """
+ filter_q = {"identifier": [nsd_id, ns_instance_id], "operationStates": ["ANY"], "operationTypes": ["ANY"]}
+ if op_state:
+ filter_q["operationStates"].append(op_state)
+ if command:
+ filter_q["operationTypes"].append(command)
+ # self.logger.debug("Db query is: {}".format(filter_q))
+ subscribers = []
+ try:
+ subscribers = self.db.get_list(self.subscriber_collection, filter_q)
+ subscribers = self._format_nslcm_subscribers(subscribers, event_details)
+ except Exception as e:
+ error_text = type(e).__name__ + ": " + str(e)
+ self.logger.debug("Error getting nslcm subscribers: {}".format(error_text))
+ finally:
+ return subscribers
+
+
+class NsdNotification(NotificationBase):
+
+ def __init__(self, db):
+ """
+ Constructor of the class
+ """
+ super().__init__(db)
+ # TODO will update this once support is there from subscription
+ self.response_models = {}
+ self.subscriber_collection = None
+
+
+class VnfdNotification(NotificationBase):
+
+ def __init__(self, db):
+ """
+ Constructor of the class
+ """
+ super().__init__(db)
+ # TODO will update this once support is there from subscription
+ self.response_models = {}
+ self.subscriber_collection = None