def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
python类db_for_read()的实例源码
def validate(self, value, model_instance):
if self.remote_field.parent_link:
return
super(ForeignKey, self).validate(value, model_instance)
if value is None:
return
using = router.db_for_read(model_instance.__class__, instance=model_instance)
qs = self.remote_field.model._default_manager.using(using).filter(
**{self.remote_field.field_name: value}
)
qs = qs.complex_filter(self.get_limit_choices_to())
if not qs.exists():
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={
'model': self.remote_field.model._meta.verbose_name, 'pk': value,
'field': self.remote_field.field_name, 'value': value,
}, # 'pk' is included for backwards compatibility
)
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
table = connections[db].ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connections[db].cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connections[db].ops.value_to_db_datetime(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
table = connections[db].ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connections[db].cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connections[db].ops.value_to_db_datetime(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
table = connections[db].ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connections[db].cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connections[db].ops.value_to_db_datetime(now)])
return cursor.fetchone() is not None
def validate(self, value, model_instance):
if self.remote_field.parent_link:
return
super(models.ForeignKey, self).validate(value, model_instance)
if value is None:
return
using = router.db_for_read(self.rel.to, instance=model_instance)
qs = self.remote_field.model._default_manager.using(using).filter(
**{self.remote_field.field_name: value}
)
qs = qs.complex_filter(self.get_limit_choices_to())
if not qs.exists():
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={
'model': self.remote_field.model._meta.verbose_name, 'pk': value,
'field': self.remote_field.field_name, 'value': value,
}, # 'pk' is included for backwards compatibility
)
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def validate(self, value, model_instance):
if self.remote_field.parent_link:
return
super(ForeignKey, self).validate(value, model_instance)
if value is None:
return
using = router.db_for_read(self.remote_field.model, instance=model_instance)
qs = self.remote_field.model._default_manager.using(using).filter(
**{self.remote_field.field_name: value}
)
qs = qs.complex_filter(self.get_limit_choices_to())
if not qs.exists():
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={
'model': self.remote_field.model._meta.verbose_name, 'pk': value,
'field': self.remote_field.field_name, 'value': value,
}, # 'pk' is included for backwards compatibility
)
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def ready(self):
for db in settings.DATABASES:
name = db['NAME']
db_wrapper_class = import_string(db['ENGINE'] + '.base.DatabaseWrapper')
base_model = getattr(db_wrapper_class, 'base_model', None)
if base_model:
models = apps.get_models()
for model in models:
if name == router.db_for_read(model):
for k, v in base_model.__dict__:
if k == 'objects':
model_manager = getattr(model, 'objects', None)
if model_manager:
manager_cls = model_manager.__class__
custom_cls = v.__class__
new_manager = type('AnyBackendCustomManager', (custom_cls, manager_cls), {})
setattr(model, 'objects', new_manager())
else:
setattr(model, 'objects', v)
elif not k.startswith('__'):
setattr(model, k ,v)
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def validate(self, value, model_instance):
if self.remote_field.parent_link:
return
super(ForeignKey, self).validate(value, model_instance)
if value is None:
return
using = router.db_for_read(self.remote_field.model, instance=model_instance)
qs = self.remote_field.model._default_manager.using(using).filter(
**{self.remote_field.field_name: value}
)
qs = qs.complex_filter(self.get_limit_choices_to())
if not qs.exists():
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={
'model': self.remote_field.model._meta.verbose_name, 'pk': value,
'field': self.remote_field.field_name, 'value': value,
}, # 'pk' is included for backwards compatibility
)
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def validate(self, value, model_instance):
if self.remote_field.parent_link:
return
super(ForeignKey, self).validate(value, model_instance)
if value is None:
return
using = router.db_for_read(model_instance.__class__, instance=model_instance)
qs = self.remote_field.model._default_manager.using(using).filter(
**{self.remote_field.field_name: value}
)
qs = qs.complex_filter(self.get_limit_choices_to())
if not qs.exists():
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={
'model': self.remote_field.model._meta.verbose_name, 'pk': value,
'field': self.remote_field.field_name, 'value': value,
}, # 'pk' is included for backwards compatibility
)
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
table = connections[db].ops.quote_name(self._table)
cursor = connections[db].cursor()
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connections[db].ops.value_to_db_datetime(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
table = connections[db].ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connections[db].cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connections[db].ops.value_to_db_datetime(now)])
return cursor.fetchone() is not None
def has_key(self, key, version=None):
key = self.make_key(key, version=version)
self.validate_key(key)
db = router.db_for_read(self.cache_model_class)
connection = connections[db]
table = connection.ops.quote_name(self._table)
if settings.USE_TZ:
now = datetime.utcnow()
else:
now = datetime.now()
now = now.replace(microsecond=0)
with connection.cursor() as cursor:
cursor.execute("SELECT cache_key FROM %s "
"WHERE cache_key = %%s and expires > %%s" % table,
[key, connection.ops.adapt_datetimefield_value(now)])
return cursor.fetchone() is not None
