ironic/ironic/common/image_service.py
Pavlo Shchelokovskyy 63e0ff2f6c Rework keystone auth for glance
this patch changes the way glance client is instantiated, using
keystoneauth sessions and adapters.

In order to support glance API endpoint discovery from keystone catalog
and more unified way of client loading,
many options in `[glance]` config sections are deprecated,
mostly those that specified a (set of) glance API endpoint(s)
or parts of glance API address.
Instead, a single option `[glance]endpoint_override` must be used when
required to access a specific (possibly load-balanced)
glance API endpoint without discovering it from keystone catalog.

Another set of deprecated options are those that are duplicating
keystoneauth session options in [glance] section.

Also, intrinsic support for parsing the glance API URL from image ref
set to the full glance REST path to the image is removed as it was not
working any way since an 'http(s)://' image ref is not treated
as a glance image.

Change-Id: I6a93b71ac097e951dfc93fd1ee4d7ef483514f2c
Partial-Bug: #1699547
Closes-Bug: #1699542
2017-11-17 11:40:14 -05:00

292 lines
11 KiB
Python

# Copyright 2010 OpenStack Foundation
# Copyright 2013 Hewlett-Packard Development Company, L.P.
# 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 abc
import datetime
import os
import shutil
from oslo_log import log
from oslo_utils import importutils
from oslo_utils import uuidutils
import requests
import sendfile
import six
from six.moves import http_client
import six.moves.urllib.parse as urlparse
from ironic.common import exception
from ironic.common.i18n import _
from ironic.common import utils
from ironic.conf import CONF
IMAGE_CHUNK_SIZE = 1024 * 1024 # 1mb
LOG = log.getLogger(__name__)
# TODO(pas-ha) in Queens change default to '2',
# but keep the versioned import in place (less work for possible Glance v3)
def GlanceImageService(client=None, version=None, context=None):
module_str = 'ironic.common.glance_service'
if version is None:
version = CONF.glance.glance_api_version
module = importutils.import_versioned_module(module_str, version,
'image_service')
service_class = getattr(module, 'GlanceImageService')
return service_class(client, version, context)
@six.add_metaclass(abc.ABCMeta)
class BaseImageService(object):
"""Provides retrieval of disk images."""
@abc.abstractmethod
def validate_href(self, image_href):
"""Validate image reference.
:param image_href: Image reference.
:raises: exception.ImageRefValidationFailed.
:returns: Information needed to further operate with an image.
"""
@abc.abstractmethod
def download(self, image_href, image_file):
"""Downloads image to specified location.
:param image_href: Image reference.
:param image_file: File object to write data to.
:raises: exception.ImageRefValidationFailed.
:raises: exception.ImageDownloadFailed.
"""
@abc.abstractmethod
def show(self, image_href):
"""Get dictionary of image properties.
:param image_href: Image reference.
:raises: exception.ImageRefValidationFailed.
:returns: dictionary of image properties. It has three of them: 'size',
'updated_at' and 'properties'. 'updated_at' attribute is a naive
UTC datetime object.
"""
class HttpImageService(BaseImageService):
"""Provides retrieval of disk images using HTTP."""
def validate_href(self, image_href, secret=False):
"""Validate HTTP image reference.
:param image_href: Image reference.
:param secret: Specify if image_href being validated should not be
shown in exception message.
:raises: exception.ImageRefValidationFailed if HEAD request failed or
returned response code not equal to 200.
:returns: Response to HEAD request.
"""
output_url = 'secreturl' if secret else image_href
try:
response = requests.head(image_href)
if response.status_code != http_client.OK:
raise exception.ImageRefValidationFailed(
image_href=output_url,
reason=_("Got HTTP code %s instead of 200 in response to "
"HEAD request.") % response.status_code)
except requests.RequestException as e:
raise exception.ImageRefValidationFailed(image_href=output_url,
reason=six.text_type(e))
return response
def download(self, image_href, image_file):
"""Downloads image to specified location.
:param image_href: Image reference.
:param image_file: File object to write data to.
:raises: exception.ImageRefValidationFailed if GET request returned
response code not equal to 200.
:raises: exception.ImageDownloadFailed if:
* IOError happened during file write;
* GET request failed.
"""
try:
response = requests.get(image_href, stream=True)
if response.status_code != http_client.OK:
raise exception.ImageRefValidationFailed(
image_href=image_href,
reason=_("Got HTTP code %s instead of 200 in response to "
"GET request.") % response.status_code)
with response.raw as input_img:
shutil.copyfileobj(input_img, image_file, IMAGE_CHUNK_SIZE)
except (requests.RequestException, IOError) as e:
raise exception.ImageDownloadFailed(image_href=image_href,
reason=six.text_type(e))
def show(self, image_href):
"""Get dictionary of image properties.
:param image_href: Image reference.
:raises: exception.ImageRefValidationFailed if:
* HEAD request failed;
* HEAD request returned response code not equal to 200;
* Content-Length header not found in response to HEAD request.
:returns: dictionary of image properties. It has three of them: 'size',
'updated_at' and 'properties'. 'updated_at' attribute is a naive
UTC datetime object.
"""
response = self.validate_href(image_href)
image_size = response.headers.get('Content-Length')
if image_size is None:
raise exception.ImageRefValidationFailed(
image_href=image_href,
reason=_("Cannot determine image size as there is no "
"Content-Length header specified in response "
"to HEAD request."))
# Parse last-modified header to return naive datetime object
str_date = response.headers.get('Last-Modified')
date = None
if str_date:
http_date_format_strings = [
'%a, %d %b %Y %H:%M:%S GMT', # RFC 822
'%A, %d-%b-%y %H:%M:%S GMT', # RFC 850
'%a %b %d %H:%M:%S %Y' # ANSI C
]
for fmt in http_date_format_strings:
try:
date = datetime.datetime.strptime(str_date, fmt)
break
except ValueError:
continue
return {
'size': int(image_size),
'updated_at': date,
'properties': {}
}
class FileImageService(BaseImageService):
"""Provides retrieval of disk images available locally on the conductor."""
def validate_href(self, image_href):
"""Validate local image reference.
:param image_href: Image reference.
:raises: exception.ImageRefValidationFailed if source image file
doesn't exist.
:returns: Path to image file if it exists.
"""
image_path = urlparse.urlparse(image_href).path
if not os.path.isfile(image_path):
raise exception.ImageRefValidationFailed(
image_href=image_href,
reason=_("Specified image file not found."))
return image_path
def download(self, image_href, image_file):
"""Downloads image to specified location.
:param image_href: Image reference.
:param image_file: File object to write data to.
:raises: exception.ImageRefValidationFailed if source image file
doesn't exist.
:raises: exception.ImageDownloadFailed if exceptions were raised while
writing to file or creating hard link.
"""
source_image_path = self.validate_href(image_href)
dest_image_path = image_file.name
local_device = os.stat(dest_image_path).st_dev
try:
# We should have read and write access to source file to create
# hard link to it.
if (local_device == os.stat(source_image_path).st_dev and
os.access(source_image_path, os.R_OK | os.W_OK)):
image_file.close()
os.remove(dest_image_path)
os.link(source_image_path, dest_image_path)
else:
filesize = os.path.getsize(source_image_path)
with open(source_image_path, 'rb') as input_img:
sendfile.sendfile(image_file.fileno(), input_img.fileno(),
0, filesize)
except Exception as e:
raise exception.ImageDownloadFailed(image_href=image_href,
reason=six.text_type(e))
def show(self, image_href):
"""Get dictionary of image properties.
:param image_href: Image reference.
:raises: exception.ImageRefValidationFailed if image file specified
doesn't exist.
:returns: dictionary of image properties. It has three of them: 'size',
'updated_at' and 'properties'. 'updated_at' attribute is a naive
UTC datetime object.
"""
source_image_path = self.validate_href(image_href)
return {
'size': os.path.getsize(source_image_path),
'updated_at': utils.unix_file_modification_datetime(
source_image_path),
'properties': {}
}
protocol_mapping = {
'http': HttpImageService,
'https': HttpImageService,
'file': FileImageService,
'glance': GlanceImageService,
}
def get_image_service(image_href, client=None, version=None, context=None):
"""Get image service instance to download the image.
:param image_href: String containing href to get image service for.
:param client: Glance client to be used for download, used only if
image_href is Glance href.
:param version: Version of Glance API to use, used only if image_href is
Glance href.
:param context: request context, used only if image_href is Glance href.
:raises: exception.ImageRefValidationFailed if no image service can
handle specified href.
:returns: Instance of an image service class that is able to download
specified image.
"""
scheme = urlparse.urlparse(image_href).scheme.lower()
if not scheme:
if uuidutils.is_uuid_like(six.text_type(image_href)):
cls = GlanceImageService
else:
raise exception.ImageRefValidationFailed(
image_href=image_href,
reason=_('Scheme-less image href is not a UUID.'))
else:
cls = protocol_mapping.get(scheme)
if not cls:
raise exception.ImageRefValidationFailed(
image_href=image_href,
reason=_('Image download protocol %s is not supported.'
) % scheme)
if cls == GlanceImageService:
return cls(client, version, context)
return cls()