/usr/share/pyshared/glance/store/filesystem.py is in python-glance 2012.1.3+stable~20120821-120fcf-0ubuntu1.5.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 | # vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright 2010 OpenStack, LLC
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""
A simple filesystem-backed store
"""
import errno
import hashlib
import logging
import os
import urlparse
from glance.common import cfg
from glance.common import exception
from glance.common import utils
import glance.store
import glance.store.base
import glance.store.location
logger = logging.getLogger('glance.store.filesystem')
class StoreLocation(glance.store.location.StoreLocation):
"""Class describing a Filesystem URI"""
def process_specs(self):
self.scheme = self.specs.get('scheme', 'file')
self.path = self.specs.get('path')
def get_uri(self):
return "file://%s" % self.path
def parse_uri(self, uri):
"""
Parse URLs. This method fixes an issue where credentials specified
in the URL are interpreted differently in Python 2.6.1+ than prior
versions of Python.
"""
pieces = urlparse.urlparse(uri)
assert pieces.scheme in ('file', 'filesystem')
self.scheme = pieces.scheme
path = (pieces.netloc + pieces.path).strip()
if path == '':
reason = _("No path specified in URI: %s") % uri
logger.error(reason)
raise exception.BadStoreUri('No path specified')
self.path = path
class ChunkedFile(object):
"""
We send this back to the Glance API server as
something that can iterate over a large file
"""
CHUNKSIZE = 65536
def __init__(self, filepath):
self.filepath = filepath
self.fp = open(self.filepath, 'rb')
def __iter__(self):
"""Return an iterator over the image file"""
try:
while True:
chunk = self.fp.read(ChunkedFile.CHUNKSIZE)
if chunk:
yield chunk
else:
break
finally:
self.close()
def close(self):
"""Close the internal file pointer"""
if self.fp:
self.fp.close()
self.fp = None
class Store(glance.store.base.Store):
datadir_opt = cfg.StrOpt('filesystem_store_datadir')
def configure_add(self):
"""
Configure the Store to use the stored configuration options
Any store that needs special configuration should implement
this method. If the store was not able to successfully configure
itself, it should raise `exception.BadStoreConfiguration`
"""
self.conf.register_opt(self.datadir_opt)
self.datadir = self.conf.filesystem_store_datadir
if self.datadir is None:
reason = _("Could not find %s in configuration options.") % \
'filesystem_store_datadir'
logger.error(reason)
raise exception.BadStoreConfiguration(store_name="filesystem",
reason=reason)
if not os.path.exists(self.datadir):
msg = _("Directory to write image files does not exist "
"(%s). Creating.") % self.datadir
logger.info(msg)
try:
os.makedirs(self.datadir)
except IOError:
reason = _("Unable to create datadir: %s") % self.datadir
logger.error(reason)
raise exception.BadStoreConfiguration(store_name="filesystem",
reason=reason)
def get(self, location):
"""
Takes a `glance.store.location.Location` object that indicates
where to find the image file, and returns a tuple of generator
(for reading the image file) and image_size
:param location `glance.store.location.Location` object, supplied
from glance.store.location.get_location_from_uri()
:raises `glance.exception.NotFound` if image does not exist
"""
loc = location.store_location
filepath = loc.path
if not os.path.exists(filepath):
raise exception.NotFound(_("Image file %s not found") % filepath)
else:
msg = _("Found image at %s. Returning in ChunkedFile.") % filepath
logger.debug(msg)
return (ChunkedFile(filepath), None)
def delete(self, location):
"""
Takes a `glance.store.location.Location` object that indicates
where to find the image file to delete
:location `glance.store.location.Location` object, supplied
from glance.store.location.get_location_from_uri()
:raises NotFound if image does not exist
:raises Forbidden if cannot delete because of permissions
"""
loc = location.store_location
fn = loc.path
if os.path.exists(fn):
try:
logger.debug(_("Deleting image at %(fn)s") % locals())
os.unlink(fn)
except OSError:
raise exception.Forbidden(_("You cannot delete file %s") % fn)
else:
raise exception.NotFound(_("Image file %s does not exist") % fn)
def add(self, image_id, image_file, image_size):
"""
Stores an image file with supplied identifier to the backend
storage system and returns an `glance.store.ImageAddResult` object
containing information about the stored image.
:param image_id: The opaque image identifier
:param image_file: The image data to write, as a file-like object
:param image_size: The size of the image data to write, in bytes
:retval `glance.store.ImageAddResult` object
:raises `glance.common.exception.Duplicate` if the image already
existed
:note By default, the backend writes the image data to a file
`/<DATADIR>/<ID>`, where <DATADIR> is the value of
the filesystem_store_datadir configuration option and <ID>
is the supplied image ID.
"""
filepath = os.path.join(self.datadir, str(image_id))
if os.path.exists(filepath):
raise exception.Duplicate(_("Image file %s already exists!")
% filepath)
checksum = hashlib.md5()
bytes_written = 0
try:
with open(filepath, 'wb') as f:
for buf in utils.chunkreadable(image_file,
ChunkedFile.CHUNKSIZE):
bytes_written += len(buf)
checksum.update(buf)
f.write(buf)
except IOError as e:
if e.errno in [errno.EFBIG, errno.ENOSPC]:
raise exception.StorageFull()
elif e.errno == errno.EACCES:
raise exception.StorageWriteDenied()
else:
raise
checksum_hex = checksum.hexdigest()
logger.debug(_("Wrote %(bytes_written)d bytes to %(filepath)s with "
"checksum %(checksum_hex)s") % locals())
return ('file://%s' % filepath, bytes_written, checksum_hex)
glance.store.register_store(__name__, ['filesystem', 'file'])
|