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Diffstat (limited to 'module/lib/beaker/ext/database.py')
| -rw-r--r-- | module/lib/beaker/ext/database.py | 165 |
1 files changed, 0 insertions, 165 deletions
diff --git a/module/lib/beaker/ext/database.py b/module/lib/beaker/ext/database.py deleted file mode 100644 index 701e6f7d2..000000000 --- a/module/lib/beaker/ext/database.py +++ /dev/null @@ -1,165 +0,0 @@ -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 -pool = None -types = None - -class DatabaseNamespaceManager(OpenResourceNamespaceManager): - metadatas = SyncDict() - tables = SyncDict() - - @classmethod - def _init_dependencies(cls): - global sa, pool, types - if sa is not None: - return - try: - import sqlalchemy as sa - import sqlalchemy.pool as pool - from sqlalchemy import types - except ImportError: - raise InvalidCacheBackendError("Database cache backend requires " - "the 'sqlalchemy' library") - - def __init__(self, namespace, url=None, sa_opts=None, optimistic=False, - table_name='beaker_cache', data_dir=None, lock_dir=None, - **params): - """Creates a database namespace manager - - ``url`` - SQLAlchemy compliant db url - ``sa_opts`` - A dictionary of SQLAlchemy keyword options to initialize the engine - with. - ``optimistic`` - Use optimistic session locking, note that this will result in an - additional select when updating a cache value to compare version - numbers. - ``table_name`` - The table name to use in the database for the cache. - """ - OpenResourceNamespaceManager.__init__(self, namespace) - - if sa_opts is None: - sa_opts = params - - 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) - - # Check to see if the table's been created before - url = url or sa_opts['sa.url'] - table_key = url + table_name - def make_cache(): - # Check to see if we have a connection pool open already - meta_key = url + table_name - def make_meta(): - # SQLAlchemy pops the url, this ensures it sticks around - # later - sa_opts['sa.url'] = url - engine = sa.engine_from_config(sa_opts, 'sa.') - meta = sa.MetaData() - meta.bind = engine - return meta - meta = DatabaseNamespaceManager.metadatas.get(meta_key, make_meta) - # Create the table object and cache it now - cache = sa.Table(table_name, meta, - sa.Column('id', types.Integer, primary_key=True), - sa.Column('namespace', types.String(255), nullable=False), - sa.Column('accessed', types.DateTime, nullable=False), - sa.Column('created', types.DateTime, nullable=False), - sa.Column('data', types.PickleType, nullable=False), - sa.UniqueConstraint('namespace') - ) - cache.create(checkfirst=True) - return cache - self.hash = {} - self._is_new = False - self.loaded = False - self.cache = DatabaseNamespaceManager.tables.get(table_key, make_cache) - - 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): - # If we already loaded the data, don't bother loading it again - if self.loaded: - self.flags = flags - return - - cache = self.cache - result = sa.select([cache.c.data], - cache.c.namespace==self.namespace - ).execute().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'): - cache = self.cache - if self._is_new: - cache.insert().execute(namespace=self.namespace, data=self.hash, - accessed=datetime.now(), - created=datetime.now()) - self._is_new = False - else: - cache.update(cache.c.namespace==self.namespace).execute( - data=self.hash, accessed=datetime.now()) - self.flags = None - - def do_remove(self): - cache = self.cache - cache.delete(cache.c.namespace==self.namespace).execute() - self.hash = {} - - # We can retain the fact that we did a load attempt, but since the - # file is gone this will be a new namespace should it be saved. - self._is_new = True - - def __getitem__(self, key): - return self.hash[key] - - def __contains__(self, key): - return self.hash.has_key(key) - - 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 DatabaseContainer(Container): - namespace_manager = DatabaseNamespaceManager |