Files
pretix_cgo/src/pretix/base/services/tasks.py
Martin Gross 0b20d3f6f8 Organizer/MultiEvent-Exports (#1684)
Co-authored-by: Raphael Michel <michel@rami.io>
2020-06-16 11:06:40 +02:00

141 lines
4.4 KiB
Python

"""
This code has been taken from
https://blog.hypertrack.io/2016/10/08/dealing-with-database-transactions-in-django-celery/
Usage:
from pretix.base.services.async import TransactionAwareTask
@task(base=TransactionAwareTask)
def task_…():
"""
import cProfile
import os
import random
import time
from django.conf import settings
from django.db import transaction
from django_scopes import scope, scopes_disabled
from pretix.base.metrics import (
pretix_task_duration_seconds, pretix_task_runs_total,
)
from pretix.base.models import Event, Organizer, User
from pretix.celery_app import app
class ProfiledTask(app.Task):
def __call__(self, *args, **kwargs):
if settings.PROFILING_RATE > 0 and random.random() < settings.PROFILING_RATE / 100:
profiler = cProfile.Profile()
profiler.enable()
t0 = time.perf_counter()
ret = super().__call__(*args, **kwargs)
tottime = time.perf_counter() - t0
profiler.disable()
profiler.dump_stats(os.path.join(settings.PROFILE_DIR, '{time:.0f}_{tottime:.3f}_celery_{t}.pstat'.format(
t=self.name, tottime=tottime, time=time.time()
)))
else:
t0 = time.perf_counter()
ret = super().__call__(*args, **kwargs)
tottime = time.perf_counter() - t0
if settings.METRICS_ENABLED:
pretix_task_duration_seconds.observe(tottime, task_name=self.name)
return ret
def on_failure(self, exc, task_id, args, kwargs, einfo):
if settings.METRICS_ENABLED:
expected = False
for t in self.throws:
if isinstance(exc, t):
expected = True
break
pretix_task_runs_total.inc(1, task_name=self.name, status="expected-error" if expected else "error")
return super().on_failure(exc, task_id, args, kwargs, einfo)
def on_success(self, retval, task_id, args, kwargs):
if settings.METRICS_ENABLED:
pretix_task_runs_total.inc(1, task_name=self.name, status="success")
return super().on_success(retval, task_id, args, kwargs)
class EventTask(app.Task):
def __call__(self, *args, **kwargs):
if 'event_id' in kwargs:
event_id = kwargs.get('event_id')
with scopes_disabled():
event = Event.objects.select_related('organizer').get(pk=event_id)
del kwargs['event_id']
kwargs['event'] = event
elif 'event' in kwargs:
event_id = kwargs.get('event')
with scopes_disabled():
event = Event.objects.select_related('organizer').get(pk=event_id)
kwargs['event'] = event
else:
args = list(args)
event_id = args[0]
with scopes_disabled():
event = Event.objects.select_related('organizer').get(pk=event_id)
args[0] = event
with scope(organizer=event.organizer):
ret = super().__call__(*args, **kwargs)
return ret
class OrganizerUserTask(app.Task):
def __call__(self, *args, **kwargs):
organizer_id = kwargs['organizer']
with scopes_disabled():
organizer = Organizer.objects.get(pk=organizer_id)
kwargs['organizer'] = organizer
user_id = kwargs['user']
user = User.objects.get(pk=user_id)
kwargs['user'] = user
with scope(organizer=organizer):
ret = super().__call__(*args, **kwargs)
return ret
class ProfiledEventTask(ProfiledTask, EventTask):
pass
class ProfiledOrganizerUserTask(ProfiledTask, OrganizerUserTask):
pass
class TransactionAwareTask(ProfiledTask):
"""
Task class which is aware of django db transactions and only executes tasks
after transaction has been committed
"""
def apply_async(self, *args, **kwargs):
"""
Unlike the default task in celery, this task does not return an async
result
"""
transaction.on_commit(
lambda: super(TransactionAwareTask, self).apply_async(*args, **kwargs)
)
class TransactionAwareProfiledEventTask(ProfiledEventTask):
def apply_async(self, *args, **kwargs):
"""
Unlike the default task in celery, this task does not return an async
result
"""
transaction.on_commit(
lambda: super(TransactionAwareProfiledEventTask, self).apply_async(*args, **kwargs)
)