# Copyright 2015 OpenStack Foundation
# 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
import glance_store as store_api
from glance_store import backend
from oslo_concurrency import processutils as putils
from oslo_config import cfg
from oslo_log import log as logging
from oslo_utils import encodeutils
from oslo_utils import excutils
from stevedore import named
from taskflow.patterns import linear_flow as lf
from taskflow import retry
from taskflow import task
from taskflow.types import failure
from glance.async_ import utils
from glance.common import exception
from glance.common.scripts.image_import import main as image_import
from glance.common.scripts import utils as script_utils
from glance.i18n import _, _LE, _LI
LOG = logging.getLogger(__name__)
CONF = cfg.CONF
class _CreateImage(task.Task):
default_provides = 'image_id'
def __init__(self, task_id, task_type, task_repo, image_repo,
image_factory):
self.task_id = task_id
self.task_type = task_type
self.task_repo = task_repo
self.image_repo = image_repo
self.image_factory = image_factory
super(_CreateImage, self).__init__(
name='%s-CreateImage-%s' % (task_type, task_id))
def execute(self):
task = script_utils.get_task(self.task_repo, self.task_id)
if task is None:
return
task_input = script_utils.unpack_task_input(task)
image = image_import.create_image(
self.image_repo, self.image_factory,
task_input.get('image_properties'), self.task_id)
LOG.debug("Task %(task_id)s created image %(image_id)s",
{'task_id': task.task_id, 'image_id': image.image_id})
return image.image_id
def revert(self, *args, **kwargs):
# TODO(NiallBunting): Deleting the image like this could be considered
# a brute force way of reverting images. It may be worth checking if
# data has been written.
result = kwargs.get('result', None)
if result is not None:
if kwargs.get('flow_failures', None) is not None:
image = self.image_repo.get(result)
LOG.debug("Deleting image whilst reverting.")
image.delete()
self.image_repo.remove(image)
class _ImportToFS(task.Task):
default_provides = 'file_path'
def __init__(self, task_id, task_type, task_repo, uri):
self.task_id = task_id
self.task_type = task_type
self.task_repo = task_repo
self.uri = uri
super(_ImportToFS, self).__init__(
name='%s-ImportToFS-%s' % (task_type, task_id))
# NOTE(abhishekk): Use reserved 'os_glance_tasks_store' for tasks,
# the else part will be removed once old way of configuring store
# is deprecated.
if CONF.enabled_backends:
self.store = store_api.get_store_from_store_identifier(
'os_glance_tasks_store')
else:
if CONF.task.work_dir is None:
msg = (_("%(task_id)s of %(task_type)s not configured "
"properly. Missing work dir: %(work_dir)s") %
{'task_id': self.task_id,
'task_type': self.task_type,
'work_dir': CONF.task.work_dir})
raise exception.BadTaskConfiguration(msg)
self.store = self._build_store()
def _build_store(self):
# NOTE(flaper87): Due to the nice glance_store api (#sarcasm), we're
# forced to build our own config object, register the required options
# (and by required I mean *ALL* of them, even the ones we don't want),
# and create our own store instance by calling a private function.
# This is certainly unfortunate but it's the best we can do until the
# glance_store refactor is done. A good thing is that glance_store is
# under our team's management and it gates on Glance so changes to
# this API will (should?) break task's tests.
conf = cfg.ConfigOpts()
backend.register_opts(conf)
conf.set_override('filesystem_store_datadir',
CONF.task.work_dir,
group='glance_store')
# NOTE(flaper87): Do not even try to judge me for this... :(
# With the glance_store refactor, this code will change, until
# that happens, we don't have a better option and this is the
# least worst one, IMHO.
store = backend._load_store(conf, 'file')
if store is None:
msg = (_("%(task_id)s of %(task_type)s not configured "
"properly. Could not load the filesystem store") %
{'task_id': self.task_id, 'task_type': self.task_type})
raise exception.BadTaskConfiguration(msg)
store.configure()
return store
def execute(self, image_id):
"""Create temp file into store and return path to it
:param image_id: Glance Image ID
"""
# NOTE(flaper87): We've decided to use a separate `work_dir` for
# this task - and tasks coming after this one - as a way to expect
# users to configure a local store for pre-import works on the image
# to happen.
#
# While using any path should be "technically" fine, it's not what
# we recommend as the best solution. For more details on this, please
# refer to the comment in the `_ImportToStore.execute` method.
data = script_utils.get_image_data_iter(self.uri)
path = self.store.add(image_id, data, 0, context=None)[0]
try:
# NOTE(flaper87): Consider moving this code to a common
# place that other tasks can consume as well.
stdout, stderr = putils.trycmd('qemu-img', 'info',
'--output=json', path,
prlimit=utils.QEMU_IMG_PROC_LIMITS,
log_errors=putils.LOG_ALL_ERRORS)
except OSError as exc:
with excutils.save_and_reraise_exception():
exc_message = encodeutils.exception_to_unicode(exc)
msg = _LE('Failed to execute security checks on the image '
'%(task_id)s: %(exc)s')
LOG.error(msg, {'task_id': self.task_id, 'exc': exc_message})
metadata = json.loads(stdout)
backing_file = metadata.get('backing-filename')
if backing_file is not None:
msg = _("File %(path)s has invalid backing file "
"%(bfile)s, aborting.") % {'path': path,
'bfile': backing_file}
raise RuntimeError(msg)
try:
data_file = metadata['format-specific']['data']['data-file']
except KeyError:
data_file = None
if data_file is not None:
msg = _("File %(path)s has invalid data-file "
"%(dfile)s, aborting.") % {"path": path,
"dfile": data_file}
raise RuntimeError(msg)
return path
def revert(self, image_id, result, **kwargs):
if isinstance(result, failure.Failure):
LOG.exception(_LE('Task: %(task_id)s failed to import image '
'%(image_id)s to the filesystem.'),
{'task_id': self.task_id, 'image_id': image_id})
return
if os.path.exists(result.split("file://")[-1]):
if CONF.enabled_backends:
store_api.delete(result, 'os_glance_tasks_store')
else:
store_api.delete_from_backend(result)
class _DeleteFromFS(task.Task):
def __init__(self, task_id, task_type):
self.task_id = task_id
self.task_type = task_type
super(_DeleteFromFS, self).__init__(
name='%s-DeleteFromFS-%s' % (task_type, task_id))
def execute(self, file_path):
"""Remove file from the backend
:param file_path: path to the file being deleted
"""
if CONF.enabled_backends:
store_api.delete(file_path, 'os_glance_tasks_store')
else:
store_api.delete_from_backend(file_path)
class _ImportToStore(task.Task):
def __init__(self, task_id, task_type, image_repo, uri, backend):
self.task_id = task_id
self.task_type = task_type
self.image_repo = image_repo
self.uri = uri
self.backend = backend
super(_ImportToStore, self).__init__(
name='%s-ImportToStore-%s' % (task_type, task_id))
def execute(self, image_id, file_path=None):
"""Bringing the introspected image to back end store
:param image_id: Glance Image ID
:param file_path: path to the image file
"""
# NOTE(flaper87): There are a couple of interesting bits in the
# interaction between this task and the `_ImportToFS` one. I'll try
# to cover them in this comment.
#
# NOTE(flaper87):
# `_ImportToFS` downloads the image to a dedicated `work_dir` which
# needs to be configured in advance (please refer to the config option
# docs for more info). The motivation behind this is also explained in
# the `_ImportToFS.execute` method.
#
# Due to the fact that we have an `_ImportToFS` task which downloads
# the image data already, we need to be as smart as we can in this task
# to avoid downloading the data several times and reducing the copy or
# write times. There are several scenarios where the interaction
# between this task and `_ImportToFS` could be improved. All these
# scenarios assume the `_ImportToFS` task has been executed before
# and/or in a more abstract scenario, that `file_path` is being
# provided.
#
# Scenario 1: FS Store is Remote, introspection enabled,
# conversion disabled
#
# In this scenario, the user would benefit from having the scratch path
# being the same path as the fs store. Only one write would happen and
# an extra read will happen in order to introspect the image. Note that
# this read is just for the image headers and not the entire file.
#
# Scenario 2: FS Store is remote, introspection enabled,
# conversion enabled
#
# In this scenario, the user would benefit from having a *local* store
# into which the image can be converted. This will require downloading
# the image locally, converting it and then copying the converted image
# to the remote store.
#
# Scenario 3: FS Store is local, introspection enabled,
# conversion disabled
# Scenario 4: FS Store is local, introspection enabled,
# conversion enabled
#
# In both these scenarios the user shouldn't care if the FS
# store path and the work dir are the same, therefore probably
# benefit, about the scratch path and the FS store being the
# same from a performance perspective. Space wise, regardless
# of the scenario, the user will have to account for it in
# advance.
#
# Lets get to it and identify the different scenarios in the
# implementation
image = self.image_repo.get(image_id)
image.status = 'saving'
self.image_repo.save(image)
# NOTE(flaper87): Let's dance... and fall
#
# Unfortunately, because of the way our domain layers work and
# the checks done in the FS store, we can't simply rename the file
# and set the location. To do that, we'd have to duplicate the logic
# of every and each of the domain factories (quota, location, etc)
# and we'd also need to hack the FS store to prevent it from raising
# a "duplication path" error. I'd rather have this task copying the
# image bits one more time than duplicating all that logic.
#
# Since I don't think this should be the definitive solution, I'm
# leaving the code below as a reference for what should happen here
# once the FS store and domain code will be able to handle this case.
#
# if file_path is None:
# image_import.set_image_data(image, self.uri, None)
# return
# NOTE(flaper87): Don't assume the image was stored in the
# work_dir. Think in the case this path was provided by another task.
# Also, lets try to neither assume things nor create "logic"
# dependencies between this task and `_ImportToFS`
#
# base_path = os.path.dirname(file_path.split("file://")[-1])
# NOTE(flaper87): Hopefully just scenarios #3 and #4. I say
# hopefully because nothing prevents the user to use the same
# FS store path as a work dir
#
# image_path = os.path.join(base_path, image_id)
#
# if (base_path == CONF.glance_store.filesystem_store_datadir or
# base_path in CONF.glance_store.filesystem_store_datadirs):
# os.rename(file_path, image_path)
#
# image_import.set_image_data(image, image_path, None)
try:
image_import.set_image_data(image,
file_path or self.uri, self.task_id,
backend=self.backend)
except IOError as e:
msg = (_('Uploading the image failed due to: %(exc)s') %
{'exc': encodeutils.exception_to_unicode(e)})
LOG.error(msg)
raise exception.UploadException(message=msg)
# NOTE(flaper87): We need to save the image again after the locations
# have been set in the image.
self.image_repo.save(image)
class _SaveImage(task.Task):
def __init__(self, task_id, task_type, image_repo):
self.task_id = task_id
self.task_type = task_type
self.image_repo = image_repo
super(_SaveImage, self).__init__(
name='%s-SaveImage-%s' % (task_type, task_id))
def execute(self, image_id):
"""Transition image status to active
:param image_id: Glance Image ID
"""
new_image = self.image_repo.get(image_id)
if new_image.status == 'saving':
# NOTE(flaper87): THIS IS WRONG!
# we should be doing atomic updates to avoid
# race conditions. This happens in other places
# too.
new_image.status = 'active'
self.image_repo.save(new_image)
class _CompleteTask(task.Task):
def __init__(self, task_id, task_type, task_repo):
self.task_id = task_id
self.task_type = task_type
self.task_repo = task_repo
super(_CompleteTask, self).__init__(
name='%s-CompleteTask-%s' % (task_type, task_id))
def execute(self, image_id):
"""Finishing the task flow
:param image_id: Glance Image ID
"""
task = script_utils.get_task(self.task_repo, self.task_id)
if task is None:
return
try:
task.succeed({'image_id': image_id})
except Exception as e:
# Note: The message string contains Error in it to indicate
# in the task.message that it's a error message for the user.
# TODO(nikhil): need to bring back save_and_reraise_exception when
# necessary
log_msg = _LE("Task ID %(task_id)s failed. Error: %(exc_type)s: "
"%(e)s")
LOG.exception(log_msg, {'exc_type': str(type(e)),
'e': encodeutils.exception_to_unicode(e),
'task_id': task.task_id})
err_msg = _("Error: %(exc_type)s: %(e)s")
task.fail(err_msg % {'exc_type': str(type(e)),
'e': encodeutils.exception_to_unicode(e)})
finally:
self.task_repo.save(task)
LOG.info(_LI("%(task_id)s of %(task_type)s completed"),
{'task_id': self.task_id, 'task_type': self.task_type})
def _get_import_flows(**kwargs):
# NOTE(flaper87): Until we have a better infrastructure to enable
# and disable tasks plugins, hard-code the tasks we know exist,
# instead of loading everything from the namespace. This guarantees
# both, the load order of these plugins and the fact that no random
# plugins will be added/loaded until we feel comfortable with this.
# Future patches will keep using NamedExtensionManager but they'll
# rely on a config option to control this process.
extensions = named.NamedExtensionManager('glance.flows.import',
names=['ovf_process',
'convert',
'introspect'],
name_order=True,
invoke_on_load=True,
invoke_kwds=kwargs)
for ext in extensions.extensions:
yield ext.obj
[docs]
def get_flow(**kwargs):
"""Return task flow
:param task_id: Task ID
:param task_type: Type of the task
:param task_repo: Task repo
:param image_repo: Image repository used
:param image_factory: Glance Image Factory
:param uri: uri for the image file
"""
task_id = kwargs.get('task_id')
task_type = kwargs.get('task_type')
task_repo = kwargs.get('task_repo')
image_repo = kwargs.get('image_repo')
image_factory = kwargs.get('image_factory')
uri = kwargs.get('uri')
backend = kwargs.get('backend')
flow = lf.Flow(task_type, retry=retry.AlwaysRevert()).add(
_CreateImage(task_id, task_type, task_repo, image_repo, image_factory))
import_to_store = _ImportToStore(task_id, task_type, image_repo, uri,
backend)
try:
# NOTE(flaper87): ImportToLocal and DeleteFromLocal shouldn't be here.
# Ideally, we should have the different import flows doing this for us
# and this function should clean up duplicated tasks. For example, say
# 2 flows need to have a local copy of the image - ImportToLocal - in
# order to be able to complete the task - i.e Introspect-. In that
# case, the introspect.get_flow call should add both, ImportToLocal and
# DeleteFromLocal, to the flow and this function will reduce the
# duplicated calls to those tasks by creating a linear flow that
# ensures those are called before the other tasks. For now, I'm
# keeping them here, though.
limbo = lf.Flow(task_type).add(_ImportToFS(task_id,
task_type,
task_repo,
uri))
for subflow in _get_import_flows(**kwargs):
limbo.add(subflow)
# NOTE(flaper87): We have hard-coded 2 tasks,
# if there aren't more than 2, it means that
# no subtask has been registered.
if len(limbo) > 1:
flow.add(limbo)
# NOTE(flaper87): Until this implementation gets smarter,
# make sure ImportToStore is called *after* the imported
# flow stages. If not, the image will be set to saving state
# invalidating tasks like Introspection or Convert.
flow.add(import_to_store)
# NOTE(flaper87): Since this is an "optional" task but required
# when `limbo` is executed, we're adding it in its own subflow
# to isolate it from the rest of the flow.
delete_flow = lf.Flow(task_type).add(_DeleteFromFS(task_id,
task_type))
flow.add(delete_flow)
else:
flow.add(import_to_store)
except exception.BadTaskConfiguration as exc:
# NOTE(flaper87): If something goes wrong with the load of
# import tasks, make sure we go on.
LOG.error(_LE('Bad task configuration: %s'), exc.message)
flow.add(import_to_store)
flow.add(
_SaveImage(task_id, task_type, image_repo),
_CompleteTask(task_id, task_type, task_repo)
)
return flow
