debian-celery/celery/fixups/django.py

238 lines
7.9 KiB
Python

from __future__ import absolute_import
import io
import os
import sys
import warnings
from kombu.utils import cached_property, symbol_by_name
from datetime import datetime
from importlib import import_module
from celery import signals
from celery.exceptions import FixupWarning
__all__ = ['DjangoFixup', 'fixup']
ERR_NOT_INSTALLED = """\
Environment variable DJANGO_SETTINGS_MODULE is defined
but Django is not installed. Will not apply Django fixups!
"""
def _maybe_close_fd(fh):
try:
os.close(fh.fileno())
except (AttributeError, OSError, TypeError):
# TypeError added for celery#962
pass
def fixup(app, env='DJANGO_SETTINGS_MODULE'):
SETTINGS_MODULE = os.environ.get(env)
if SETTINGS_MODULE and 'django' not in app.loader_cls.lower():
try:
import django # noqa
except ImportError:
warnings.warn(FixupWarning(ERR_NOT_INSTALLED))
else:
return DjangoFixup(app).install()
class DjangoFixup(object):
def __init__(self, app):
self.app = app
self.app.set_default()
def install(self):
# Need to add project directory to path
sys.path.append(os.getcwd())
self.app.loader.now = self.now
self.app.loader.mail_admins = self.mail_admins
signals.worker_init.connect(self.on_worker_init)
return self
def on_worker_init(self, **kwargs):
# keep reference
self._worker_fixup = DjangoWorkerFixup(self.app).install()
def now(self, utc=False):
return datetime.utcnow() if utc else self._now()
def mail_admins(self, subject, body, fail_silently=False, **kwargs):
return self._mail_admins(subject, body, fail_silently=fail_silently)
@cached_property
def _mail_admins(self):
return symbol_by_name('django.core.mail:mail_admins')
@cached_property
def _now(self):
try:
return symbol_by_name('django.utils.timezone:now')
except (AttributeError, ImportError): # pre django-1.4
return datetime.now
class DjangoWorkerFixup(object):
_db_recycles = 0
def __init__(self, app):
self.app = app
self.db_reuse_max = self.app.conf.get('CELERY_DB_REUSE_MAX', None)
self._db = import_module('django.db')
self._cache = import_module('django.core.cache')
self._settings = symbol_by_name('django.conf:settings')
# Database-related exceptions.
DatabaseError = symbol_by_name('django.db:DatabaseError')
try:
import MySQLdb as mysql
_my_database_errors = (mysql.DatabaseError,
mysql.InterfaceError,
mysql.OperationalError)
except ImportError:
_my_database_errors = () # noqa
try:
import psycopg2 as pg
_pg_database_errors = (pg.DatabaseError,
pg.InterfaceError,
pg.OperationalError)
except ImportError:
_pg_database_errors = () # noqa
try:
import sqlite3
_lite_database_errors = (sqlite3.DatabaseError,
sqlite3.InterfaceError,
sqlite3.OperationalError)
except ImportError:
_lite_database_errors = () # noqa
try:
import cx_Oracle as oracle
_oracle_database_errors = (oracle.DatabaseError,
oracle.InterfaceError,
oracle.OperationalError)
except ImportError:
_oracle_database_errors = () # noqa
try:
self._close_old_connections = symbol_by_name(
'django.db:close_old_connections',
)
except (ImportError, AttributeError):
self._close_old_connections = None
self.database_errors = (
(DatabaseError, ) +
_my_database_errors +
_pg_database_errors +
_lite_database_errors +
_oracle_database_errors
)
def validate_models(self):
import django
try:
django.setup()
except AttributeError:
pass
s = io.StringIO()
try:
from django.core.management.validation import get_validation_errors
except ImportError:
from django.core.management.base import BaseCommand
cmd = BaseCommand()
cmd.stdout, cmd.stderr = sys.stdout, sys.stderr
cmd.check()
else:
num_errors = get_validation_errors(s, None)
if num_errors:
raise RuntimeError(
'One or more Django models did not validate:\n{0}'.format(
s.getvalue()))
def install(self):
signals.beat_embedded_init.connect(self.close_database)
signals.worker_ready.connect(self.on_worker_ready)
signals.task_prerun.connect(self.on_task_prerun)
signals.task_postrun.connect(self.on_task_postrun)
signals.worker_process_init.connect(self.on_worker_process_init)
self.validate_models()
self.close_database()
self.close_cache()
return self
def on_worker_process_init(self, **kwargs):
# the parent process may have established these,
# so need to close them.
# calling db.close() on some DB connections will cause
# the inherited DB conn to also get broken in the parent
# process so we need to remove it without triggering any
# network IO that close() might cause.
try:
for c in self._db.connections.all():
if c and c.connection:
_maybe_close_fd(c.connection)
except AttributeError:
if self._db.connection and self._db.connection.connection:
_maybe_close_fd(self._db.connection.connection)
# use the _ version to avoid DB_REUSE preventing the conn.close() call
self._close_database()
self.close_cache()
def on_task_prerun(self, sender, **kwargs):
"""Called before every task."""
if not getattr(sender.request, 'is_eager', False):
self.close_database()
def on_task_postrun(self, sender, **kwargs):
# See http://groups.google.com/group/django-users/
# browse_thread/thread/78200863d0c07c6d/
if not getattr(sender.request, 'is_eager', False):
self.close_database()
self.close_cache()
def close_database(self, **kwargs):
if self._close_old_connections:
return self._close_old_connections() # Django 1.6
if not self.db_reuse_max:
return self._close_database()
if self._db_recycles >= self.db_reuse_max * 2:
self._db_recycles = 0
self._close_database()
self._db_recycles += 1
def _close_database(self):
try:
funs = [conn.close for conn in self._db.connections]
except AttributeError:
if hasattr(self._db, 'close_old_connections'): # django 1.6
funs = [self._db.close_old_connections]
else:
# pre multidb, pending deprication in django 1.6
funs = [self._db.close_connection]
for close in funs:
try:
close()
except self.database_errors as exc:
str_exc = str(exc)
if 'closed' not in str_exc and 'not connected' not in str_exc:
raise
def close_cache(self):
try:
self._cache.cache.close()
except (TypeError, AttributeError):
pass
def on_worker_ready(self, **kwargs):
if self._settings.DEBUG:
warnings.warn('Using settings.DEBUG leads to a memory leak, never '
'use this setting in production environments!')