# glance.async_.flows.plugins.image_conversion

# Source code for glance.async_.flows.plugins.image_conversion

    # Copyright 2018 Red Hat, Inc.
    # 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.

    import json
    import os

    from oslo_concurrency import processutils as putils
    from oslo_config import cfg
    from oslo_log import log as logging
    from oslo_utils import excutils
    from oslo_utils.imageutils import format_inspector
    from taskflow.patterns import linear_flow as lf
    from taskflow import task

    from glance.async_ import utils
    from glance.i18n import _, _LI

    LOG = logging.getLogger(__name__)

    conversion_plugin_opts = [
        cfg.StrOpt('output_format',
                   default='raw',
                   choices=('qcow2', 'raw', 'vmdk'),
                   help=_("""
    Desired output format for image conversion plugin.

    Provide a valid image format to which the conversion plugin
    will convert the image before storing it to the back-end.

    Note, if the Image Conversion plugin for image import is defined, users
    should only upload disk formats that are supported by `quemu-img` otherwise
    the conversion and import will fail.

    Possible values:
        * qcow2
        * raw
        * vmdk

    Related Options:
        * disk_formats
    """)),
    ]

    CONF = cfg.CONF

    CONF.register_opts(conversion_plugin_opts, group='image_conversion')

    class _ConvertImage(task.Task):

        default_provides = 'file_path'

        def __init__(self, context, task_id, task_type, action_wrapper,
                     stores):
            self.context = context
            self.task_id = task_id
            self.task_type = task_type
            self.action_wrapper = action_wrapper
            self.stores = stores
            self.image_id = action_wrapper.image_id
            self.dest_path = ""
            self.src_path = ""
            self.python = CONF.wsgi.python_interpreter
            super(_ConvertImage, self).__init__(
                name='%s-Convert_Image-%s' % (task_type, task_id))

        def execute(self, file_path, **kwargs):
            with self.action_wrapper as action:
                return self._execute(action, file_path, **kwargs)

        def _inspect_path(self, path):
            """Return a FormatInspector for path.

            This encapsulates the act of inspecting a file, running safety checks,
            and raising/logging if anything goes wrong. If nothing fails, return
            the FileInspector for the file.
            """
            # Use our own cautious inspector module (if we have one for this
            # format) to make sure a file is the format the submitter claimed
            # it is and that it passes some basic safety checks _before_ we run
            # qemu-img on it.
            # See https://bugs.launchpad.net/nova/+bug/2059809 for details.
            try:
                inspector = format_inspector.detect_file_format(path)
                inspector.safety_check()
            except format_inspector.SafetyCheckFailed as e:
                nonfatal = set(CONF.image_format.gpt_safety_checks_nonfatal)
                fatal = e.failures.keys() - nonfatal
                if inspector.NAME == 'gpt' and not fatal:
                    LOG.warning('Non-fatal %s', e)
                else:
                    LOG.error('%s %s', str(inspector), e)
                    raise RuntimeError('Image has disallowed configuration')
            except format_inspector.ImageFormatError as e:
                LOG.error('Image failed format inspection: %s', e)
                raise RuntimeError('Image format detection failed')
            except Exception as e:
                LOG.exception('Unknown error inspecting image format: %s', e)
                raise RuntimeError('Unable to inspect image')
            return inspector

        def _execute(self, action, file_path, **kwargs):

            target_format = CONF.image_conversion.output_format
            # TODO(jokke): Once we support other schemas we need to take them into
            # account and handle the paths here.
            self.src_path = file_path.split('file://')[-1]
            dest_path = "%(path)s.%(target)s" % {'path': self.src_path,
                                                 'target': target_format}
            self.dest_path = dest_path
            source_format = action.image_disk_format
            inspector = self._inspect_path(self.src_path)

            detected_format = str(inspector)
            if detected_format == 'gpt':
                # FIXME(danms): We need to consider GPT to be raw for compatibility
                detected_format = 'raw'

            if detected_format == 'iso':
                if source_format == 'iso':
                    # NOTE(abhishekk): Excluding conversion and preserving image
                    # disk_format as `iso` only
                    LOG.debug("Avoiding conversion of an image %s having"
                              " `iso` disk format.", self.image_id)
                    return file_path

                # NOTE(abhishekk): Raising error as image detected as ISO but
                # claimed as different format
                LOG.error('Image claimed to be %s format but format '
                          'inspection found: ISO', source_format)
                raise RuntimeError("Image has disallowed configuration")
            elif detected_format != source_format:
                LOG.error('Image claimed to be %s format failed format '
                          'inspection', source_format)
                raise RuntimeError('Image format mismatch')

            try:
                stdout, stderr = putils.trycmd("qemu-img", "info",
                                               "-f", source_format,
                                               "--output=json",
                                               self.src_path,
                                               prlimit=utils.QEMU_IMG_PROC_LIMITS,
                                               python_exec=self.python,
                                               log_errors=putils.LOG_ALL_ERRORS,)
            except OSError as exc:
                with excutils.save_and_reraise_exception():
                    msg = ("Failed to do introspection as part of image "
                           "conversion for %(iid)s: %(err)s")
                    LOG.error(msg, {'iid': self.image_id, 'err': exc})

            if stderr:
                raise RuntimeError(stderr)

            metadata = json.loads(stdout)
            if metadata.get('format') != source_format:
                LOG.error('Image claiming to be %s reported as %s by qemu-img',
                          source_format, metadata.get('format', 'unknown'))
                raise RuntimeError('Image metadata disagrees about format')

            virtual_size = metadata.get('virtual-size', 0)
            action.set_image_attribute(virtual_size=virtual_size)

            if 'backing-filename' in metadata:
                LOG.warning('Refusing to process QCOW image with a backing file')
                raise RuntimeError(
                    'QCOW images with backing files are not allowed')

            try:
                data_file = metadata['format-specific']['data']['data-file']
            except KeyError:
                data_file = None
            if data_file is not None:
                raise RuntimeError(
                    'QCOW images with data-file set are not allowed')

            if metadata.get('format') == 'vmdk':
                create_type = metadata.get(
                    'format-specific', {}).get(
                        'data', {}).get('create-type')
                allowed = CONF.image_format.vmdk_allowed_types
                if not create_type:
                    raise RuntimeError(_('Unable to determine VMDK create-type'))
                if not len(allowed):
                    LOG.warning(_('Refusing to process VMDK file as '
                                  'vmdk_allowed_types is empty'))
                    raise RuntimeError(_('Image is a VMDK, but no VMDK createType '
                                         'is specified'))
                if create_type not in allowed:
                    LOG.warning(_('Refusing to process VMDK file with create-type '
                                  'of %r which is not in allowed set of: %s'),
                                create_type, ','.join(allowed))
                    raise RuntimeError(_('Invalid VMDK create-type specified'))

            if source_format == target_format:
                LOG.debug("Source is already in target format, "
                          "not doing conversion for %s", self.image_id)
                return file_path

            try:
                stdout, stderr = putils.trycmd('qemu-img', 'convert',
                                               '-f', source_format,
                                               '-O', target_format,
                                               self.src_path, dest_path,
                                               log_errors=putils.LOG_ALL_ERRORS)
            except OSError as exc:
                with excutils.save_and_reraise_exception():
                    msg = "Failed to do image conversion for %(iid)s: %(err)s"
                    LOG.error(msg, {'iid': self.image_id, 'err': exc})

            if stderr:
                raise RuntimeError(stderr)

            dest_inspector = self._inspect_path(dest_path)
            dest_format = str(dest_inspector)
            if dest_format == 'gpt':
                # FIXME(danms): We need to consider GPT to be raw for compatibility
                dest_format = 'raw'

            if target_format != dest_format:
                # If someone hid one format inside another, we should reject it
                # as we could be about to embed a vmdk in a 'raw' or similar.
                LOG.error('Image detected as %s after conversion to %s',
                          dest_format, target_format)
                raise RuntimeError('Converted image in unexpected format')
            action.set_image_attribute(disk_format=target_format,
                                       container_format='bare')
            new_size = os.stat(dest_path).st_size
            action.set_image_attribute(size=new_size)
            LOG.info(_LI('Updated image %s size=%i disk_format=%s'),
                     self.image_id, new_size, target_format)

            os.remove(self.src_path)

            return "file://%s" % dest_path

        def revert(self, result=None, **kwargs):
            # NOTE(flaper87): If result is None, it probably
            # means this task failed. Otherwise, we would have
            # a result from its execution.
            if result is not None:
                LOG.debug("Image conversion failed.")
                if os.path.exists(self.dest_path):
                    os.remove(self.dest_path)

            # NOTE(abhishekk): If we failed to convert the image, then none
            # of the _ImportToStore() tasks could have run, so we need
            # to move all stores out of "importing" to "failed".
            with self.action_wrapper as action:
                action.set_image_attribute(status='queued')
                if self.stores:
                    action.remove_importing_stores(self.stores)
                    action.add_failed_stores(self.stores)

            if self.src_path:
                try:
                    os.remove(self.src_path)
                except FileNotFoundError:
                    # NOTE(abhishekk): We must have raced with something
                    # else, so this is not a problem
                    pass

    def get_flow(**kwargs):
        """Return task flow for no-op.

        :param context: request context
        :param task_id: Task ID.
        :param task_type: Type of the task.
        :param image_repo: Image repository used.
        :param image_id: Image ID
        :param action_wrapper: An api_image_import.ActionWrapper.
        """
        context = kwargs.get('context')
        task_id = kwargs.get('task_id')
        task_type = kwargs.get('task_type')
        action_wrapper = kwargs.get('action_wrapper')
        stores = kwargs.get('backend', [])

        return lf.Flow(task_type).add(
            _ConvertImage(context, task_id, task_type, action_wrapper, stores)
        )

this page last updated: 2026-03-18 20:42:57

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