def provide_celery(self, app: Flask) -> Celery:
celery = Celery(
app.import_name,
backend=app.config["CELERY_RESULT_BACKEND"],
broker=app.config["CELERY_BROKER_URL"],
)
celery.conf["CELERYD_HIJACK_ROOT_LOGGER"] = False
celery.conf["CELERY_IMPORTS"] = (
"matcher.tasks.export",
"matcher.tasks.import_",
"matcher.tasks.object",
)
celery.conf.update(app.config)
celery.conf.ONCE = {
"backend": "celery_once.backends.Redis",
"settings": {
"url": app.config["CELERY_RESULT_BACKEND"],
"default_timeout": 60 * 60,
},
}
class ContextTask(Task):
def __call__(self, *args, **kwargs):
with app.app_context():
return self.run(*args, **kwargs)
class OnceTask(QueueOnce):
def __call__(self, *args, **kwargs):
with app.app_context():
return self.run(*args, **kwargs)
celery.Task = ContextTask
celery.OnceTask = OnceTask
def handle_celery_postrun(retval=None, *args, **kwargs):
"""After each Celery task, teardown our db session"""
if app.config["SQLALCHEMY_COMMIT_ON_TEARDOWN"]:
if not isinstance(retval, Exception):
db.session.commit()
# If we aren't in an eager request (i.e. Flask will perform teardown), then teardown
if not app.config["CELERY_ALWAYS_EAGER"]:
db.session.remove()
task_postrun.connect(handle_celery_postrun)
return celery
