def load_storage_driver(conf, cache, control_mode=False):
"""Loads a storage driver and returns it.
The driver's initializer will be passed conf and cache as
its positional args.
:param conf: Configuration instance to use for loading the
driver. Must include a 'drivers' group.
:param cache: Cache instance that the driver can (optionally)
use to reduce latency for some operations.
:param control_mode: (Default False). Determines which
driver type to load; if False, the data driver is
loaded. If True, the control driver is loaded.
"""
mode = 'control' if control_mode else 'data'
driver_type = 'marconi.queues.{0}.storage'.format(mode)
try:
mgr = driver.DriverManager(driver_type,
conf['drivers'].storage,
invoke_on_load=True,
invoke_args=[conf, cache])
return mgr.driver
except RuntimeError as exc:
LOG.exception(exc)
raise errors.InvalidDriver(exc)
def cache(self):
LOG.debug(_(u'Loading proxy cache driver'))
try:
oslo_cache.register_oslo_configs(self.conf)
mgr = oslo_cache.get_cache(self.conf.cache_url)
return mgr
except RuntimeError as exc:
LOG.exception(exc)
raise errors.InvalidDriver(exc)
def transport(self):
transport_name = self.driver_conf.transport
LOG.debug(_(u'Loading transport driver: %s'), transport_name)
args = [
self.conf,
self.storage,
self.cache,
self.control,
]
try:
mgr = driver.DriverManager('marconi.queues.transport',
transport_name,
invoke_on_load=True,
invoke_args=args)
return mgr.driver
except RuntimeError as exc:
LOG.exception(exc)
raise errors.InvalidDriver(exc)