/usr/lib/python2.7/dist-packages/beaker/ext/sqla.py is in python-beaker 1.6.4-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 | import cPickle
import logging
import pickle
from datetime import datetime
from beaker.container import OpenResourceNamespaceManager, Container
from beaker.exceptions import InvalidCacheBackendError, MissingCacheParameter
from beaker.synchronization import file_synchronizer, null_synchronizer
from beaker.util import verify_directory, SyncDict
log = logging.getLogger(__name__)
sa = None
class SqlaNamespaceManager(OpenResourceNamespaceManager):
binds = SyncDict()
tables = SyncDict()
@classmethod
def _init_dependencies(cls):
global sa
if sa is not None:
return
try:
import sqlalchemy as sa
except ImportError:
raise InvalidCacheBackendError("SQLAlchemy, which is required by "
"this backend, is not installed")
def __init__(self, namespace, bind, table, data_dir=None, lock_dir=None,
**kwargs):
"""Create a namespace manager for use with a database table via
SQLAlchemy.
``bind``
SQLAlchemy ``Engine`` or ``Connection`` object
``table``
SQLAlchemy ``Table`` object in which to store namespace data.
This should usually be something created by ``make_cache_table``.
"""
OpenResourceNamespaceManager.__init__(self, namespace)
if lock_dir:
self.lock_dir = lock_dir
elif data_dir:
self.lock_dir = data_dir + "/container_db_lock"
if self.lock_dir:
verify_directory(self.lock_dir)
self.bind = self.__class__.binds.get(str(bind.url), lambda: bind)
self.table = self.__class__.tables.get('%s:%s' % (bind.url, table.name),
lambda: table)
self.hash = {}
self._is_new = False
self.loaded = False
def get_access_lock(self):
return null_synchronizer()
def get_creation_lock(self, key):
return file_synchronizer(
identifier="databasecontainer/funclock/%s" % self.namespace,
lock_dir=self.lock_dir)
def do_open(self, flags, replace):
if self.loaded:
self.flags = flags
return
select = sa.select([self.table.c.data],
(self.table.c.namespace == self.namespace))
result = self.bind.execute(select).fetchone()
if not result:
self._is_new = True
self.hash = {}
else:
self._is_new = False
try:
self.hash = result['data']
except (IOError, OSError, EOFError, cPickle.PickleError,
pickle.PickleError):
log.debug("Couln't load pickle data, creating new storage")
self.hash = {}
self._is_new = True
self.flags = flags
self.loaded = True
def do_close(self):
if self.flags is not None and (self.flags == 'c' or self.flags == 'w'):
if self._is_new:
insert = self.table.insert()
self.bind.execute(insert, namespace=self.namespace, data=self.hash,
accessed=datetime.now(), created=datetime.now())
self._is_new = False
else:
update = self.table.update(self.table.c.namespace == self.namespace)
self.bind.execute(update, data=self.hash, accessed=datetime.now())
self.flags = None
def do_remove(self):
delete = self.table.delete(self.table.c.namespace == self.namespace)
self.bind.execute(delete)
self.hash = {}
self._is_new = True
def __getitem__(self, key):
return self.hash[key]
def __contains__(self, key):
return key in self.hash
def __setitem__(self, key, value):
self.hash[key] = value
def __delitem__(self, key):
del self.hash[key]
def keys(self):
return self.hash.keys()
class SqlaContainer(Container):
namespace_manager = SqlaNamespaceManager
def make_cache_table(metadata, table_name='beaker_cache', schema_name=None):
"""Return a ``Table`` object suitable for storing cached values for the
namespace manager. Do not create the table."""
return sa.Table(table_name, metadata,
sa.Column('namespace', sa.String(255), primary_key=True),
sa.Column('accessed', sa.DateTime, nullable=False),
sa.Column('created', sa.DateTime, nullable=False),
sa.Column('data', sa.PickleType, nullable=False),
schema=schema_name if schema_name else metadata.schema)
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