Spaces:
Running
on
A10G
Running
on
A10G
File size: 5,913 Bytes
320e465 |
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 |
from abc import ABCMeta, abstractmethod
class BaseStorageBackend(metaclass=ABCMeta):
"""Abstract class of storage backends.
All backends need to implement two apis: ``get()`` and ``get_text()``.
``get()`` reads the file as a byte stream and ``get_text()`` reads the file
as texts.
"""
@abstractmethod
def get(self, filepath):
pass
@abstractmethod
def get_text(self, filepath):
pass
class MemcachedBackend(BaseStorageBackend):
"""Memcached storage backend.
Attributes:
server_list_cfg (str): Config file for memcached server list.
client_cfg (str): Config file for memcached client.
sys_path (str | None): Additional path to be appended to `sys.path`.
Default: None.
"""
def __init__(self, server_list_cfg, client_cfg, sys_path=None):
if sys_path is not None:
import sys
sys.path.append(sys_path)
try:
import mc
except ImportError:
raise ImportError('Please install memcached to enable MemcachedBackend.')
self.server_list_cfg = server_list_cfg
self.client_cfg = client_cfg
self._client = mc.MemcachedClient.GetInstance(self.server_list_cfg, self.client_cfg)
# mc.pyvector servers as a point which points to a memory cache
self._mc_buffer = mc.pyvector()
def get(self, filepath):
filepath = str(filepath)
import mc
self._client.Get(filepath, self._mc_buffer)
value_buf = mc.ConvertBuffer(self._mc_buffer)
return value_buf
def get_text(self, filepath):
raise NotImplementedError
class HardDiskBackend(BaseStorageBackend):
"""Raw hard disks storage backend."""
def get(self, filepath):
filepath = str(filepath)
with open(filepath, 'rb') as f:
value_buf = f.read()
return value_buf
def get_text(self, filepath):
filepath = str(filepath)
with open(filepath, 'r') as f:
value_buf = f.read()
return value_buf
class LmdbBackend(BaseStorageBackend):
"""Lmdb storage backend.
Args:
db_paths (str | list[str]): Lmdb database paths.
client_keys (str | list[str]): Lmdb client keys. Default: 'default'.
readonly (bool, optional): Lmdb environment parameter. If True,
disallow any write operations. Default: True.
lock (bool, optional): Lmdb environment parameter. If False, when
concurrent access occurs, do not lock the database. Default: False.
readahead (bool, optional): Lmdb environment parameter. If False,
disable the OS filesystem readahead mechanism, which may improve
random read performance when a database is larger than RAM.
Default: False.
Attributes:
db_paths (list): Lmdb database path.
_client (list): A list of several lmdb envs.
"""
def __init__(self, db_paths, client_keys='default', readonly=True, lock=False, readahead=False, **kwargs):
try:
import lmdb
except ImportError:
raise ImportError('Please install lmdb to enable LmdbBackend.')
if isinstance(client_keys, str):
client_keys = [client_keys]
if isinstance(db_paths, list):
self.db_paths = [str(v) for v in db_paths]
elif isinstance(db_paths, str):
self.db_paths = [str(db_paths)]
assert len(client_keys) == len(self.db_paths), ('client_keys and db_paths should have the same length, '
f'but received {len(client_keys)} and {len(self.db_paths)}.')
self._client = {}
for client, path in zip(client_keys, self.db_paths):
self._client[client] = lmdb.open(path, readonly=readonly, lock=lock, readahead=readahead, **kwargs)
def get(self, filepath, client_key):
"""Get values according to the filepath from one lmdb named client_key.
Args:
filepath (str | obj:`Path`): Here, filepath is the lmdb key.
client_key (str): Used for distinguishing differnet lmdb envs.
"""
filepath = str(filepath)
assert client_key in self._client, (f'client_key {client_key} is not ' 'in lmdb clients.')
client = self._client[client_key]
with client.begin(write=False) as txn:
value_buf = txn.get(filepath.encode('ascii'))
return value_buf
def get_text(self, filepath):
raise NotImplementedError
class FileClient(object):
"""A general file client to access files in different backend.
The client loads a file or text in a specified backend from its path
and return it as a binary file. it can also register other backend
accessor with a given name and backend class.
Attributes:
backend (str): The storage backend type. Options are "disk",
"memcached" and "lmdb".
client (:obj:`BaseStorageBackend`): The backend object.
"""
_backends = {
'disk': HardDiskBackend,
'memcached': MemcachedBackend,
'lmdb': LmdbBackend,
}
def __init__(self, backend='disk', **kwargs):
if backend not in self._backends:
raise ValueError(f'Backend {backend} is not supported. Currently supported ones'
f' are {list(self._backends.keys())}')
self.backend = backend
self.client = self._backends[backend](**kwargs)
def get(self, filepath, client_key='default'):
# client_key is used only for lmdb, where different fileclients have
# different lmdb environments.
if self.backend == 'lmdb':
return self.client.get(filepath, client_key)
else:
return self.client.get(filepath)
def get_text(self, filepath):
return self.client.get_text(filepath)
|