cic-stack/apps/cic-ussd/cic_ussd/tasks/ussd_session.py
2021-08-06 16:29:01 +00:00

64 lines
2.5 KiB
Python

# standard imports
import json
from datetime import timedelta
# third party imports
import celery
from celery.utils.log import get_logger
# local imports
from cic_ussd.cache import Cache, get_cached_data
from cic_ussd.db.models.base import SessionBase
from cic_ussd.db.models.ussd_session import UssdSession
from cic_ussd.error import SessionNotFoundError
from cic_ussd.tasks.base import CriticalSQLAlchemyTask
celery_app = celery.current_app
logg = get_logger(__file__)
@celery_app.task(base=CriticalSQLAlchemyTask)
def persist_session_to_db(external_session_id: str):
"""
This task initiates the saving of the session object to the database and it's removal from the in-memory storage.
:param external_session_id: The session id of the session to be saved.
:type external_session_id: str.
:return: The representation of the newly created database object or en error message if session is not found.
:rtype: str.
:raises SessionNotFoundError: If the session object is not found in memory.
:raises VersionTooLowError: If the session's version doesn't match the latest version.
"""
session = SessionBase.create_session()
cached_ussd_session = get_cached_data(external_session_id)
if cached_ussd_session:
cached_ussd_session = json.loads(cached_ussd_session)
ussd_session = session.query(UssdSession).filter_by(external_session_id=external_session_id).first()
if ussd_session:
ussd_session.update(
session=session,
user_input=cached_ussd_session.get('user_input'),
state=cached_ussd_session.get('state'),
version=cached_ussd_session.get('version'),
)
else:
ussd_session = UssdSession(
external_session_id=external_session_id,
service_code=cached_ussd_session.get('service_code'),
msisdn=cached_ussd_session.get('msisdn'),
user_input=cached_ussd_session.get('user_input'),
state=cached_ussd_session.get('state'),
version=cached_ussd_session.get('version'),
)
data = cached_ussd_session.get('data')
if data:
for key, value in data.items():
ussd_session.set_data(key=key, value=value, session=session)
session.add(ussd_session)
session.commit()
session.close()
Cache.store.expire(external_session_id, timedelta(minutes=1))
else:
session.close()
raise SessionNotFoundError('Session does not exist!')
session.close()