def _distill_storage(conn, do_create, nomanaged,
path, vol_object, vol_install, clone_path, *args):
"""
Validates and updates params when the backing storage is changed
"""
pool = None
path_is_pool = False
storage_capable = conn.check_conn_support(conn.SUPPORT_CONN_STORAGE)
if vol_object:
pass
elif not storage_capable:
pass
elif path and not nomanaged:
path = os.path.abspath(path)
vol_object, pool, path_is_pool = diskbackend.check_if_path_managed(
conn, path)
creator = None
backend = diskbackend.StorageBackend(conn, path, vol_object,
path_is_pool and pool or None)
if not do_create:
return backend, None
if backend.exists() and path is not None:
if vol_install:
raise ValueError("vol_install specified but %s exists." %
backend.path)
elif not clone_path:
return backend, None
if path or vol_install or pool or clone_path:
creator = diskbackend.StorageCreator(conn, path, pool,
vol_install, clone_path, *args)
return backend, creator
def path_exists(conn, path):
"""
Check if path exists. If we can't determine, return False
"""
if path is None:
return False
try:
(vol, pool, path_is_pool) = diskbackend.check_if_path_managed(
conn, path)
ignore = pool
if vol or path_is_pool:
return True
if not conn.is_remote():
return os.path.exists(path)
except:
pass
return False