config/sysinv/sysinv/sysinv/sysinv/common/images.py

231 lines
8.8 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# All Rights Reserved.
# Copyright (c) 2010 Citrix Systems, Inc.
#
# 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.
"""
Handling of VM disk images.
"""
import os
import re
from oslo_config import cfg
from oslo_log import log as logging
from oslo_utils import fileutils
from oslo_utils import strutils
from sysinv._i18n import _
from sysinv.common import exception
from sysinv.common import image_service as service
from sysinv.common import utils
LOG = logging.getLogger(__name__)
image_opts = [
cfg.BoolOpt('force_raw_images',
default=True,
help='Force backing images to raw format'),
]
CONF = cfg.CONF
CONF.register_opts(image_opts)
class QemuImgInfo(object):
BACKING_FILE_RE = re.compile((r"^(.*?)\s*\(actual\s+path\s*:"
r"\s+(.*?)\)\s*$"), re.I)
TOP_LEVEL_RE = re.compile(r"^([\w\d\s\_\-]+):(.*)$")
SIZE_RE = re.compile(r"\(\s*(\d+)\s+bytes\s*\)", re.I)
def __init__(self, cmd_output=None):
details = self._parse(cmd_output or '')
self.image = details.get('image')
self.backing_file = details.get('backing_file')
self.file_format = details.get('file_format')
self.virtual_size = details.get('virtual_size')
self.cluster_size = details.get('cluster_size')
self.disk_size = details.get('disk_size')
self.snapshots = details.get('snapshot_list', [])
self.encryption = details.get('encryption')
def __str__(self):
lines = [
'image: %s' % self.image,
'file_format: %s' % self.file_format,
'virtual_size: %s' % self.virtual_size,
'disk_size: %s' % self.disk_size,
'cluster_size: %s' % self.cluster_size,
'backing_file: %s' % self.backing_file,
]
if self.snapshots:
lines.append("snapshots: %s" % self.snapshots)
return "\n".join(lines)
def _canonicalize(self, field):
# Standardize on underscores/lc/no dash and no spaces
# since qemu seems to have mixed outputs here... and
# this format allows for better integration with python
# - ie for usage in kwargs and such...
field = field.lower().strip()
return re.sub('[ -]', '_', field)
def _extract_bytes(self, details):
# Replace it with the byte amount
real_size = self.SIZE_RE.search(details)
if real_size:
details = real_size.group(1)
try:
details = strutils.string_to_bytes(details, return_int=True)
except (TypeError):
pass
return details
def _extract_details(self, root_cmd, root_details, lines_after):
real_details = root_details
if root_cmd == 'backing_file':
# Replace it with the real backing file
backing_match = self.BACKING_FILE_RE.match(root_details)
if backing_match:
real_details = backing_match.group(2).strip()
elif root_cmd in ['virtual_size', 'cluster_size', 'disk_size']:
# Replace it with the byte amount (if we can convert it)
real_details = self._extract_bytes(root_details)
elif root_cmd == 'file_format':
real_details = real_details.strip().lower()
elif root_cmd == 'snapshot_list':
# Next line should be a header, starting with 'ID'
if not lines_after or not lines_after[0].startswith("ID"):
msg = _("Snapshot list encountered but no header found!")
raise ValueError(msg)
del lines_after[0]
real_details = []
# This is the sprintf pattern we will try to match
# "%-10s%-20s%7s%20s%15s"
# ID TAG VM SIZE DATE VM CLOCK (current header)
while lines_after:
line = lines_after[0]
line_pieces = line.split()
if len(line_pieces) != 6:
break
# Check against this pattern in the final position
# "%02d:%02d:%02d.%03d"
date_pieces = line_pieces[5].split(":")
if len(date_pieces) != 3:
break
real_details.append({
'id': line_pieces[0],
'tag': line_pieces[1],
'vm_size': line_pieces[2],
'date': line_pieces[3],
'vm_clock': line_pieces[4] + " " + line_pieces[5],
})
del lines_after[0]
return real_details
def _parse(self, cmd_output):
# Analysis done of qemu-img.c to figure out what is going on here
# Find all points start with some chars and then a ':' then a newline
# and then handle the results of those 'top level' items in a separate
# function.
#
# TODO(harlowja): newer versions might have a json output format
# we should switch to that whenever possible.
# see: http://bit.ly/XLJXDX
contents = {}
lines = [x for x in cmd_output.splitlines() if x.strip()]
while lines:
line = lines.pop(0)
top_level = self.TOP_LEVEL_RE.match(line)
if top_level:
root = self._canonicalize(top_level.group(1))
if not root:
continue
root_details = top_level.group(2).strip()
details = self._extract_details(root, root_details, lines)
contents[root] = details
return contents
def qemu_img_info(path):
"""Return an object containing the parsed output from qemu-img info."""
if not os.path.exists(path):
return QemuImgInfo()
out, err = utils.execute('env', 'LC_ALL=C', 'LANG=C',
'qemu-img', 'info', path)
return QemuImgInfo(out)
def convert_image(source, dest, out_format, run_as_root=False):
"""Convert image to other format."""
cmd = ('qemu-img', 'convert', '-O', out_format, source, dest)
utils.execute(*cmd, run_as_root=run_as_root)
def fetch(context, image_href, path, image_service=None):
# TODO(vish): Improve context handling and add owner and auth data
# when it is added to glance. Right now there is no
# auth checking in glance, so we assume that access was
# checked before we got here.
if not image_service:
image_service = service.Service(version=1, context=context)
with fileutils.remove_path_on_error(path):
with open(path, "wb") as image_file:
image_service.download(image_href, image_file)
def fetch_to_raw(context, image_href, path, image_service=None):
path_tmp = "%s.part" % path
fetch(context, image_href, path_tmp, image_service)
image_to_raw(image_href, path, path_tmp)
def image_to_raw(image_href, path, path_tmp):
with fileutils.remove_path_on_error(path_tmp):
data = qemu_img_info(path_tmp)
fmt = data.file_format
if fmt is None:
raise exception.ImageUnacceptable(
reason=_("'qemu-img info' parsing failed."),
image_id=image_href)
backing_file = data.backing_file
if backing_file is not None:
raise exception.ImageUnacceptable(image_id=image_href,
reason=_("fmt=%(fmt)s backed by: %(backing_file)s") %
{'fmt': fmt,
'backing_file': backing_file})
if fmt != "raw" and CONF.force_raw_images:
staged = "%s.converted" % path
LOG.debug("%s was %s, converting to raw" % (image_href, fmt))
with fileutils.remove_path_on_error(staged):
convert_image(path_tmp, staged, 'raw')
os.unlink(path_tmp)
data = qemu_img_info(staged)
if data.file_format != "raw":
raise exception.ImageConvertFailed(image_id=image_href,
reason=_("Converted to raw, but format is now %s") %
data.file_format)
os.rename(staged, path)
else:
os.rename(path_tmp, path)