# 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)