def __init__(self, root, mode="r+" ):
"""Load the TSDB located at ``path``.
``mode`` control the mode used by open()
"""
TSDBBase.__init__(self)
self.path = "/"
self.mode = mode
self.fs = get_fs(root, [])
self.load_metadata()
self.chunk_prefixes = self.metadata.get('CHUNK_PREFIXES', [])
if self.chunk_prefixes:
# the root is listed as the first prefix, don't add it again
self.fs = get_fs(root, self.chunk_prefixes[1:])
if self.metadata.has_key('MEMCACHED_URI'):
self.memcache = True
try:
import cmemcache as memcache
except ImportError:
try:
import memcache
except:
self.memcache = False
if self.memcache:
self.memcache = memcache.Client([self.metadata['MEMCACHED_URI']])
def create(klass, path, metadata=None, chunk_prefixes=[]):
"""Create a new TSDB.
``chunk_prefixes``
a list of alternate prefixes to locate chunks
"""
if metadata is None:
metadata = {}
if os.path.exists(os.path.join(path, "TSDB")):
raise TSDBAlreadyExistsError("database already exists")
metadata["CREATION_TIME"] = time.time()
metadata["CHUNK_PREFIXES"] = chunk_prefixes
if not os.path.exists(path):
os.mkdir(path)
fs = get_fs(path, [])
write_dict(fs, os.path.join("/", klass.tag), metadata)
return klass(path)
