def resolve_driver_format(self):
"""Return the driver format for self.path.
First checks self.disk_info_path for an entry.
If it's not there, calls self._get_driver_format(), and then
stores the result in self.disk_info_path
See https://bugs.launchpad.net/nova/+bug/1221190
"""
def _dict_from_line(line):
if not line:
return {}
try:
return jsonutils.loads(line)
except (TypeError, ValueError) as e:
msg = (_("Could not load line %(line)s, got error "
"%(error)s") % {
'line': line,
'error': e
})
raise exception.InvalidDiskInfo(reason=msg)
@utils.synchronized(self.disk_info_path,
external=False,
lock_path=self.lock_path)
def write_to_disk_info_file():
# Use os.open to create it without group or world write permission.
fd = os.open(self.disk_info_path, os.O_RDONLY | os.O_CREAT, 0o644)
with os.fdopen(fd, "r") as disk_info_file:
line = disk_info_file.read().rstrip()
dct = _dict_from_line(line)
if self.path in dct:
msg = _("Attempted overwrite of an existing value.")
raise exception.InvalidDiskInfo(reason=msg)
dct.update({self.path: driver_format})
tmp_path = self.disk_info_path + ".tmp"
fd = os.open(tmp_path, os.O_WRONLY | os.O_CREAT, 0o644)
with os.fdopen(fd, "w") as tmp_file:
tmp_file.write('%s\n' % jsonutils.dumps(dct))
os.rename(tmp_path, self.disk_info_path)
try:
if (self.disk_info_path is not None
and os.path.exists(self.disk_info_path)):
with open(self.disk_info_path) as disk_info_file:
line = disk_info_file.read().rstrip()
dct = _dict_from_line(line)
for path, driver_format in six.iteritems(dct):
if path == self.path:
return driver_format
driver_format = self._get_driver_format()
if self.disk_info_path is not None:
fileutils.ensure_tree(os.path.dirname(self.disk_info_path))
write_to_disk_info_file()
except OSError as e:
raise exception.DiskInfoReadWriteFail(reason=six.text_type(e))
return driver_format
def resolve_driver_format(self):
"""Return the driver format for self.path.
First checks self.disk_info_path for an entry.
If it's not there, calls self._get_driver_format(), and then
stores the result in self.disk_info_path
See https://bugs.launchpad.net/nova/+bug/1221190
"""
def _dict_from_line(line):
if not line:
return {}
try:
return jsonutils.loads(line)
except (TypeError, ValueError) as e:
msg = (_("Could not load line %(line)s, got error "
"%(error)s") % {
'line': line,
'error': unicode(e)
})
raise exception.InvalidDiskInfo(reason=msg)
@utils.synchronized(self.disk_info_path,
external=False,
lock_path=self.lock_path)
def write_to_disk_info_file():
# Use os.open to create it without group or world write permission.
fd = os.open(self.disk_info_path, os.O_RDWR | os.O_CREAT, 0o644)
with os.fdopen(fd, "r+") as disk_info_file:
line = disk_info_file.read().rstrip()
dct = _dict_from_line(line)
if self.path in dct:
msg = _("Attempted overwrite of an existing value.")
raise exception.InvalidDiskInfo(reason=msg)
dct.update({self.path: driver_format})
disk_info_file.seek(0)
disk_info_file.truncate()
disk_info_file.write('%s\n' % jsonutils.dumps(dct))
# Ensure the file is always owned by the nova user so qemu can't
# write it.
# TODO chown for windows?
# utils.chown(self.disk_info_path, owner_uid=getpass.getuser())
try:
LOG.debug('Disk info path %s' % self.disk_info_path)
if (self.disk_info_path is not None
and os.path.exists(self.disk_info_path)):
with open(self.disk_info_path) as disk_info_file:
line = disk_info_file.read().rstrip()
dct = _dict_from_line(line)
for path, driver_format in dct.iteritems():
if path == self.path:
return driver_format
driver_format = self._get_driver_format()
if self.disk_info_path is not None:
fileutils.ensure_tree(os.path.dirname(self.disk_info_path))
write_to_disk_info_file()
except OSError as e:
raise exception.DiskInfoReadWriteFail(reason=unicode(e))
return driver_format
