openstack/nova
Code Issues Proposed changes

XenAPI: define a new image handler to use vdi streaming

Browse Source 
With the new image handler, it creates an image proxy which
will use the vdi streaming function from os-xenapi to
remotely export VHD from XenServer(image upload) or import
VHD to Xenerver(image download).
The existing GlanceStore uses custom functionality to directly
manipulate files on-disk, so it has the restriction that SR's
type must be file system based: e.g. ext or nfs. The new
image handler invokes APIs formally supported by XenServer
to export/import VDI remotely, it can support other SR
types also e.g. lvm, iscsi, etc.

Note:
vdi streaming would be supported by XenServer 6.5 or above.
The function of image handler depends on os-xenapi 0.3.3 or
above, so bump os-xenapi's version to 0.3.3 and also declare
depends on the patch which bump version in openstack/requirements.

Blueprint: xenapi-image-handler-option-improvement
Change-Id: I0ad8e34808401ace9b85e1b937a542f4c4e61690
Depends-On: Ib8bc0f837c55839dc85df1d1f0c76b320b9d97b8
This commit is contained in:
jianghua wang 2017-08-25 02:11:25 +00:00 committed by Naichuan Sun
parent a7da8f257f
commit f7593ded8f
8 changed files with 285 additions and 16 deletions
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35
doc/source/admin/configuration/hypervisor-xen-api.rst
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@ -440,19 +440,30 @@ attached NFS or any other shared storage):
sr_matching_filter = "default-sr:true"
Image upload in TGZ compressed format
-------------------------------------
Use different image handler
---------------------------
To start uploading ``tgz`` compressed raw disk images to the Image service,
configure ``xenapi_image_upload_handler`` by replacing ``GlanceStore`` with
``VdiThroughDevStore``.
We support three different implementations for glance image handler. You
can choose a specific image handler based on the demand:
* ``direct_vhd``: This image handler will call XAPI plugins to directly
process the VHD files in XenServer SR(Storage Repository). So this handler
only works when the host's SR type is file system based e.g. ext, nfs.
* ``vdi_local_dev``: This image handler uploads ``tgz`` compressed raw
disk images to the glance image service.
* ``vdi_remote_stream``: With this image handler, the image data streams
between XenServer and the glance image service. As it uses the remote
APIs supported by XAPI, this plugin works for all SR types supported by
XenServer.
``direct_vhd`` is the default image handler. If want to use a different image
handler, you can change the config setting of ``image_handler`` within the
``[xenserver]`` section. For example, the following config setting is to use
``vdi_remote_stream`` as the image handler:
.. code-block:: ini
xenapi_image_upload_handler=nova.virt.xenapi.image.vdi_through_dev.VdiThroughDevStore
As opposed to:
.. code-block:: ini
xenapi_image_upload_handler=nova.virt.xenapi.image.glance.GlanceStore
[xenserver]
image_handler=vdi_remote_stream

2
lower-constraints.txt
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@ -72,7 +72,7 @@ os-service-types==1.2.0
os-traits==0.4.0
os-vif==1.7.0
os-win==3.0.0
os-xenapi==0.3.1
os-xenapi==0.3.3
osc-lib==1.10.0
oslo.cache==1.26.0
oslo.concurrency==3.26.0

7
nova/conf/xenserver.py
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@ -472,7 +472,7 @@ GlanceStore.
"""),
cfg.StrOpt('image_handler',
default='direct_vhd',
choices=('direct_vhd', 'vdi_local_dev'),
choices=('direct_vhd', 'vdi_local_dev', 'vdi_remote_stream'),
help="""
The plugin used to handle image uploads and downloads.
@ -488,6 +488,11 @@ the instance's VDI as a local disk to the VM where the OpenStack Compute
service runs in. It uploads the raw disk to glance when creating image;
When booting an instance from a glance image, it downloads the image and
streams it into the disk which is attached to the compute VM.
* ``vdi_remote_stream``: This plugin implements an image handler which works
as a proxy between glance and XenServer. The VHD streams to XenServer via
a remote import API supplied by XAPI for image download; and for image
upload, the VHD streams from XenServer via a remote export API supplied
by XAPI. This plugin works for all SR types supported by XenServer.
"""),
]

149
nova/tests/unit/virt/xenapi/image/test_vdi_stream.py Normal file
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@ -0,0 +1,149 @@
# Copyright 2017 Citrix System
# 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 mock
from os_xenapi.client import exception as xenapi_except
from os_xenapi.client import image
from nova import context
from nova import exception
from nova.image.api import API as image_api
from nova.tests.unit.virt.xenapi import stubs
from nova.virt.xenapi.image import utils
from nova.virt.xenapi.image import vdi_stream
from nova.virt.xenapi import vm_utils
class TestVdiStreamStore(stubs.XenAPITestBaseNoDB):
def setUp(self):
super(TestVdiStreamStore, self).setUp()
self.store = vdi_stream.VdiStreamStore()
self.flags(connection_url='test_url',
image_compression_level=5,
group='xenserver')
self.session = mock.Mock()
self.context = context.RequestContext(
'user', 'project', auth_token='foobar')
self.instance = {'uuid': 'e6ad57c9-115e-4b7d-a872-63cea0ac3cf2',
'system_metadata': [],
'auto_disk_config': True,
'os_type': 'default',
'xenapi_use_agent': 'true'}
@mock.patch.object(image_api, 'download',
return_value='fake_data')
@mock.patch.object(utils, 'IterableToFileAdapter',
return_value='fake_stream')
@mock.patch.object(vm_utils, 'safe_find_sr',
return_value='fake_sr_ref')
@mock.patch.object(image, 'stream_to_vdis')
def test_download_image(self, stream_to, find_sr, to_file, download):
self.store.download_image(self.context, self.session,
self.instance, 'fake_image_uuid')
download.assert_called_once_with(self.context, 'fake_image_uuid')
to_file.assert_called_once_with('fake_data')
find_sr.assert_called_once_with(self.session)
stream_to.assert_called_once_with(self.context, self.session,
self.instance, 'test_url',
'fake_sr_ref', 'fake_stream')
@mock.patch.object(image_api, 'download',
return_value='fake_data')
@mock.patch.object(utils, 'IterableToFileAdapter',
return_value='fake_stream')
@mock.patch.object(vm_utils, 'safe_find_sr',
return_value='fake_sr_ref')
@mock.patch.object(image, 'stream_to_vdis',
side_effect=xenapi_except.OsXenApiException)
def test_download_image_exception(self, stream_to, find_sr, to_file,
download):
self.assertRaises(exception.CouldNotFetchImage,
self.store.download_image,
self.context, self.session,
self.instance, 'fake_image_uuid')
@mock.patch.object(vdi_stream.VdiStreamStore, '_get_metadata',
return_value='fake_meta_data')
@mock.patch.object(image, 'stream_from_vdis',
return_value='fake_data')
@mock.patch.object(utils, 'IterableToFileAdapter',
return_value='fake_stream')
@mock.patch.object(image_api, 'update')
def test_upload_image(self, update, to_file, to_stream, get):
fake_vdi_uuids = ['fake-vdi-uuid']
self.store.upload_image(self.context, self.session,
self.instance, 'fake_image_uuid',
fake_vdi_uuids)
get.assert_called_once_with(self.context, self.instance,
'fake_image_uuid')
to_stream.assert_called_once_with(self.context, self.session,
self.instance, 'test_url',
fake_vdi_uuids, compresslevel=5)
to_file.assert_called_once_with('fake_data')
update.assert_called_once_with(self.context, 'fake_image_uuid',
'fake_meta_data', data='fake_stream')
@mock.patch.object(vdi_stream.VdiStreamStore, '_get_metadata')
@mock.patch.object(image, 'stream_from_vdis',
side_effect=xenapi_except.OsXenApiException)
@mock.patch.object(utils, 'IterableToFileAdapter',
return_value='fake_stream')
@mock.patch.object(image_api, 'update')
def test_upload_image_exception(self, update, to_file, to_stream, get):
fake_vdi_uuids = ['fake-vdi-uuid']
self.assertRaises(exception.CouldNotUploadImage,
self.store.upload_image,
self.context, self.session,
self.instance, 'fake_image_uuid',
fake_vdi_uuids)
@mock.patch.object(image_api, 'get',
return_value={})
def test_get_metadata(self, image_get):
expect_metadata = {'disk_format': 'vhd',
'container_format': 'ovf',
'auto_disk_config': 'True',
'os_type': 'default',
'size': 0}
result = self.store._get_metadata(self.context, self.instance,
'fake_image_uuid')
self.assertEqual(result, expect_metadata)
@mock.patch.object(image_api, 'get',
return_value={})
def test_get_metadata_disabled(self, image_get):
# Verify the metadata contains auto_disk_config=disabled, when
# image_auto_disk_config is ""Disabled".
self.instance['system_metadata'] = [
{"key": "image_auto_disk_config",
"value": "Disabled"}]
expect_metadata = {'disk_format': 'vhd',
'container_format': 'ovf',
'auto_disk_config': 'disabled',
'os_type': 'default',
'size': 0}
result = self.store._get_metadata(self.context, self.instance,
'fake_image_uuid')
self.assertEqual(result, expect_metadata)

3
nova/virt/xenapi/image/utils.py
View File

@ -25,7 +25,8 @@ _VDI_FORMAT_RAW = 1
IMAGE_API = image.API()
IMAGE_HANDLERS = {'direct_vhd': 'glance.GlanceStore',
'vdi_local_dev': 'vdi_through_dev.VdiThroughDevStore'}
'vdi_local_dev': 'vdi_through_dev.VdiThroughDevStore',
'vdi_remote_stream': 'vdi_stream.VdiStreamStore'}
def get_image_handler(handler_name):

85
nova/virt/xenapi/image/vdi_stream.py Normal file
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@ -0,0 +1,85 @@
# Copyright 2017 Citrix Systems
# 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.
""" This class will stream image data directly between glance and VDI.
"""
from os_xenapi.client import exception as xenapi_exception
from os_xenapi.client import image as xenapi_image
from oslo_log import log as logging
import nova.conf
from nova import exception
from nova import image
from nova import utils as nova_utils
from nova.virt.xenapi.image import utils
from nova.virt.xenapi import vm_utils
CONF = nova.conf.CONF
LOG = logging.getLogger(__name__)
IMAGE_API = image.API()
class VdiStreamStore(object):
def download_image(self, context, session, instance, image_id):
try:
host_url = CONF.xenserver.connection_url
image_data = IMAGE_API.download(context, image_id)
image_stream = utils.IterableToFileAdapter(image_data)
sr_ref = vm_utils.safe_find_sr(session)
vdis = xenapi_image.stream_to_vdis(context, session,
instance, host_url,
sr_ref, image_stream)
except xenapi_exception.OsXenApiException as e:
LOG.error("Image download failed with exception: %s", e)
raise exception.CouldNotFetchImage(image_id=image_id)
return vdis
def _get_metadata(self, context, instance, image_id):
metadata = IMAGE_API.get(context, image_id)
metadata['disk_format'] = 'vhd'
metadata['container_format'] = 'ovf'
metadata['auto_disk_config'] = str(instance['auto_disk_config'])
metadata['os_type'] = instance.get('os_type') or (
CONF.xenserver.default_os_type)
# Set size as zero, so that it will update the size in the end
# based on the uploaded image data.
metadata['size'] = 0
# Adjust the auto_disk_config value basing on instance's
# system metadata.
# TODO(mriedem): Consider adding an abstract base class for the
# various image handlers to contain common code like this.
auto_disk = nova_utils.get_auto_disk_config_from_instance(instance)
if nova_utils.is_auto_disk_config_disabled(auto_disk):
metadata['auto_disk_config'] = "disabled"
return metadata
def upload_image(self, context, session, instance, image_id, vdi_uuids):
try:
host_url = CONF.xenserver.connection_url
level = vm_utils.get_compression_level()
metadata = self._get_metadata(context, instance, image_id)
image_chunks = xenapi_image.stream_from_vdis(
context, session, instance, host_url, vdi_uuids,
compresslevel=level)
image_stream = utils.IterableToFileAdapter(image_chunks)
IMAGE_API.update(context, image_id, metadata,
data=image_stream)
except xenapi_exception.OsXenApiException as e:
LOG.error("Image upload failed with exception: %s", e)
raise exception.CouldNotUploadImage(image_id=image_id)

18
releasenotes/notes/xenapi-image-handler-7628a7221b7323e2.yaml
View File

@ -23,6 +23,24 @@ features:
an instance from a glance image, it downloads the image and streams it
into the disk which is attached to the compute VM.
* ``vdi_remote_stream``
This plugin implements an image proxy in nova compute service.
For image upload, the proxy will export a data stream for a VDI from
XenServer via the remote API supplied by XAPI; convert the stream
to the image format supported by glance; and upload the image to glance.
For image download, the proxy downloads an image stream from glance;
extracts the data stream from the image stream; and then remotely
imports the data stream to XenServer's VDI via the remote API supplied
by XAPI.
Note: Under this implementation, the image data may reside in one or
more pieces of storage of various formats on the host, but the import
and export operations interact with a single, proxied VDI object
independent of the underlying structure.
deprecations:
- |
The ``image_upload_handler`` option in the ``xenserver`` conf section

2
requirements.txt
View File

@ -58,7 +58,7 @@ os-vif!=1.8.0,>=1.7.0 # Apache-2.0
os-win>=3.0.0 # Apache-2.0
castellan>=0.16.0 # Apache-2.0
microversion-parse>=0.2.1 # Apache-2.0
os-xenapi>=0.3.1 # Apache-2.0
os-xenapi>=0.3.3 # Apache-2.0
tooz>=1.58.0 # Apache-2.0
cursive>=0.2.1 # Apache-2.0
pypowervm>=1.1.15 # Apache-2.0