# Copyright 2011 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.
from contextlib import contextmanager
import datetime
import hashlib
import os
import time
import fixtures
from oslo_utils import units
from oslotest import moxstubout
import six
# NOTE(jokke): simplified transition to py3, behaves like py2 xrange
from six.moves import range
from glance.common import exception
from glance import image_cache
# NOTE(bcwaldon): This is imported to load the registry config options
import glance.registry # noqa
from glance.tests import utils as test_utils
from glance.tests.utils import skip_if_disabled
from glance.tests.utils import xattr_writes_supported
FIXTURE_LENGTH = 1024
FIXTURE_DATA = b'*' * FIXTURE_LENGTH
[docs]class ImageCacheTestCase(object):
def _setup_fixture_file(self):
FIXTURE_FILE = six.BytesIO(FIXTURE_DATA)
self.assertFalse(self.cache.is_cached(1))
self.assertTrue(self.cache.cache_image_file(1, FIXTURE_FILE))
self.assertTrue(self.cache.is_cached(1))
@skip_if_disabled
[docs] def test_is_cached(self):
"""Verify is_cached(1) returns 0, then add something to the cache
and verify is_cached(1) returns 1.
"""
self._setup_fixture_file()
@skip_if_disabled
[docs] def test_read(self):
"""Verify is_cached(1) returns 0, then add something to the cache
and verify after a subsequent read from the cache that
is_cached(1) returns 1.
"""
self._setup_fixture_file()
buff = six.BytesIO()
with self.cache.open_for_read(1) as cache_file:
for chunk in cache_file:
buff.write(chunk)
self.assertEqual(FIXTURE_DATA, buff.getvalue())
@skip_if_disabled
[docs] def test_open_for_read(self):
"""Test convenience wrapper for opening a cache file via
its image identifier.
"""
self._setup_fixture_file()
buff = six.BytesIO()
with self.cache.open_for_read(1) as cache_file:
for chunk in cache_file:
buff.write(chunk)
self.assertEqual(FIXTURE_DATA, buff.getvalue())
@skip_if_disabled
[docs] def test_get_image_size(self):
"""Test convenience wrapper for querying cache file size via
its image identifier.
"""
self._setup_fixture_file()
size = self.cache.get_image_size(1)
self.assertEqual(FIXTURE_LENGTH, size)
@skip_if_disabled
[docs] def test_delete(self):
"""Test delete method that removes an image from the cache."""
self._setup_fixture_file()
self.cache.delete_cached_image(1)
self.assertFalse(self.cache.is_cached(1))
@skip_if_disabled
[docs] def test_delete_all(self):
"""Test delete method that removes an image from the cache."""
for image_id in (1, 2):
self.assertFalse(self.cache.is_cached(image_id))
for image_id in (1, 2):
FIXTURE_FILE = six.BytesIO(FIXTURE_DATA)
self.assertTrue(self.cache.cache_image_file(image_id,
FIXTURE_FILE))
for image_id in (1, 2):
self.assertTrue(self.cache.is_cached(image_id))
self.cache.delete_all_cached_images()
for image_id in (1, 2):
self.assertFalse(self.cache.is_cached(image_id))
@skip_if_disabled
[docs] def test_clean_stalled(self):
"""Test the clean method removes expected images."""
incomplete_file_path = os.path.join(self.cache_dir, 'incomplete', '1')
incomplete_file = open(incomplete_file_path, 'wb')
incomplete_file.write(FIXTURE_DATA)
incomplete_file.close()
self.assertTrue(os.path.exists(incomplete_file_path))
self.cache.clean(stall_time=0)
self.assertFalse(os.path.exists(incomplete_file_path))
@skip_if_disabled
[docs] def test_clean_stalled_nonzero_stall_time(self):
"""
Test the clean method removes the stalled images as expected
"""
incomplete_file_path_1 = os.path.join(self.cache_dir,
'incomplete', '1')
incomplete_file_path_2 = os.path.join(self.cache_dir,
'incomplete', '2')
for f in (incomplete_file_path_1, incomplete_file_path_2):
incomplete_file = open(f, 'wb')
incomplete_file.write(FIXTURE_DATA)
incomplete_file.close()
mtime = os.path.getmtime(incomplete_file_path_1)
pastday = (datetime.datetime.fromtimestamp(mtime) -
datetime.timedelta(days=1))
atime = int(time.mktime(pastday.timetuple()))
mtime = atime
os.utime(incomplete_file_path_1, (atime, mtime))
self.assertTrue(os.path.exists(incomplete_file_path_1))
self.assertTrue(os.path.exists(incomplete_file_path_2))
self.cache.clean(stall_time=3600)
self.assertFalse(os.path.exists(incomplete_file_path_1))
self.assertTrue(os.path.exists(incomplete_file_path_2))
@skip_if_disabled
[docs] def test_prune(self):
"""
Test that pruning the cache works as expected...
"""
self.assertEqual(0, self.cache.get_cache_size())
# Add a bunch of images to the cache. The max cache size for the cache
# is set to 5KB and each image is 1K. We use 11 images in this test.
# The first 10 are added to and retrieved from cache in the same order.
# Then, the 11th image is added to cache but not retrieved before we
# prune. We should see only 5 images left after pruning, and the
# images that are least recently accessed should be the ones pruned...
for x in range(10):
FIXTURE_FILE = six.BytesIO(FIXTURE_DATA)
self.assertTrue(self.cache.cache_image_file(x, FIXTURE_FILE))
self.assertEqual(10 * units.Ki, self.cache.get_cache_size())
# OK, hit the images that are now cached...
for x in range(10):
buff = six.BytesIO()
with self.cache.open_for_read(x) as cache_file:
for chunk in cache_file:
buff.write(chunk)
# Add a new image to cache.
# This is specifically to test the bug: 1438564
FIXTURE_FILE = six.BytesIO(FIXTURE_DATA)
self.assertTrue(self.cache.cache_image_file(99, FIXTURE_FILE))
self.cache.prune()
self.assertEqual(5 * units.Ki, self.cache.get_cache_size())
# Ensure images 0, 1, 2, 3, 4 & 5 are not cached anymore
for x in range(0, 6):
self.assertFalse(self.cache.is_cached(x),
"Image %s was cached!" % x)
# Ensure images 6, 7, 8 and 9 are still cached
for x in range(6, 10):
self.assertTrue(self.cache.is_cached(x),
"Image %s was not cached!" % x)
# Ensure the newly added image, 99, is still cached
self.assertTrue(self.cache.is_cached(99), "Image 99 was not cached!")
@skip_if_disabled
[docs] def test_prune_to_zero(self):
"""Test that an image_cache_max_size of 0 doesn't kill the pruner
This is a test specifically for LP #1039854
"""
self.assertEqual(0, self.cache.get_cache_size())
FIXTURE_FILE = six.BytesIO(FIXTURE_DATA)
self.assertTrue(self.cache.cache_image_file('xxx', FIXTURE_FILE))
self.assertEqual(1024, self.cache.get_cache_size())
# OK, hit the image that is now cached...
buff = six.BytesIO()
with self.cache.open_for_read('xxx') as cache_file:
for chunk in cache_file:
buff.write(chunk)
self.config(image_cache_max_size=0)
self.cache.prune()
self.assertEqual(0, self.cache.get_cache_size())
self.assertFalse(self.cache.is_cached('xxx'))
@skip_if_disabled
[docs] def test_queue(self):
"""
Test that queueing works properly
"""
self.assertFalse(self.cache.is_cached(1))
self.assertFalse(self.cache.is_queued(1))
FIXTURE_FILE = six.BytesIO(FIXTURE_DATA)
self.assertTrue(self.cache.queue_image(1))
self.assertTrue(self.cache.is_queued(1))
self.assertFalse(self.cache.is_cached(1))
# Should not return True if the image is already
# queued for caching...
self.assertFalse(self.cache.queue_image(1))
self.assertFalse(self.cache.is_cached(1))
# Test that we return False if we try to queue
# an image that has already been cached
self.assertTrue(self.cache.cache_image_file(1, FIXTURE_FILE))
self.assertFalse(self.cache.is_queued(1))
self.assertTrue(self.cache.is_cached(1))
self.assertFalse(self.cache.queue_image(1))
self.cache.delete_cached_image(1)
for x in range(3):
self.assertTrue(self.cache.queue_image(x))
self.assertEqual(['0', '1', '2'],
self.cache.get_queued_images())
[docs] def test_open_for_write_good(self):
"""
Test to see if open_for_write works in normal case
"""
# test a good case
image_id = '1'
self.assertFalse(self.cache.is_cached(image_id))
with self.cache.driver.open_for_write(image_id) as cache_file:
cache_file.write(b'a')
self.assertTrue(self.cache.is_cached(image_id),
"Image %s was NOT cached!" % image_id)
# make sure it has tidied up
incomplete_file_path = os.path.join(self.cache_dir,
'incomplete', image_id)
invalid_file_path = os.path.join(self.cache_dir, 'invalid', image_id)
self.assertFalse(os.path.exists(incomplete_file_path))
self.assertFalse(os.path.exists(invalid_file_path))
[docs] def test_open_for_write_with_exception(self):
"""
Test to see if open_for_write works in a failure case for each driver
This case is where an exception is raised while the file is being
written. The image is partially filled in cache and filling wont resume
so verify the image is moved to invalid/ directory
"""
# test a case where an exception is raised while the file is open
image_id = '1'
self.assertFalse(self.cache.is_cached(image_id))
try:
with self.cache.driver.open_for_write(image_id):
raise IOError
except Exception as e:
self.assertIsInstance(e, IOError)
self.assertFalse(self.cache.is_cached(image_id),
"Image %s was cached!" % image_id)
# make sure it has tidied up
incomplete_file_path = os.path.join(self.cache_dir,
'incomplete', image_id)
invalid_file_path = os.path.join(self.cache_dir, 'invalid', image_id)
self.assertFalse(os.path.exists(incomplete_file_path))
self.assertTrue(os.path.exists(invalid_file_path))
[docs] def test_caching_iterator(self):
"""
Test to see if the caching iterator interacts properly with the driver
When the iterator completes going through the data the driver should
have closed the image and placed it correctly
"""
# test a case where an exception NOT raised while the file is open,
# and a consuming iterator completes
def consume(image_id):
data = [b'a', b'b', b'c', b'd', b'e', b'f']
checksum = None
caching_iter = self.cache.get_caching_iter(image_id, checksum,
iter(data))
self.assertEqual(data, list(caching_iter))
image_id = '1'
self.assertFalse(self.cache.is_cached(image_id))
consume(image_id)
self.assertTrue(self.cache.is_cached(image_id),
"Image %s was NOT cached!" % image_id)
# make sure it has tidied up
incomplete_file_path = os.path.join(self.cache_dir,
'incomplete', image_id)
invalid_file_path = os.path.join(self.cache_dir, 'invalid', image_id)
self.assertFalse(os.path.exists(incomplete_file_path))
self.assertFalse(os.path.exists(invalid_file_path))
[docs] def test_caching_iterator_handles_backend_failure(self):
"""
Test that when the backend fails, caching_iter does not continue trying
to consume data, and rolls back the cache.
"""
def faulty_backend():
data = [b'a', b'b', b'c', b'Fail', b'd', b'e', b'f']
for d in data:
if d == b'Fail':
raise exception.GlanceException('Backend failure')
yield d
def consume(image_id):
caching_iter = self.cache.get_caching_iter(image_id, None,
faulty_backend())
# exercise the caching_iter
list(caching_iter)
image_id = '1'
self.assertRaises(exception.GlanceException, consume, image_id)
# make sure bad image was not cached
self.assertFalse(self.cache.is_cached(image_id))
[docs] def test_caching_iterator_falloffend(self):
"""
Test to see if the caching iterator interacts properly with the driver
in a case where the iterator is only partially consumed. In this case
the image is only partially filled in cache and filling wont resume.
When the iterator goes out of scope the driver should have closed the
image and moved it from incomplete/ to invalid/
"""
# test a case where a consuming iterator just stops.
def falloffend(image_id):
data = [b'a', b'b', b'c', b'd', b'e', b'f']
checksum = None
caching_iter = self.cache.get_caching_iter(image_id, checksum,
iter(data))
self.assertEqual(b'a', next(caching_iter))
image_id = '1'
self.assertFalse(self.cache.is_cached(image_id))
falloffend(image_id)
self.assertFalse(self.cache.is_cached(image_id),
"Image %s was cached!" % image_id)
# make sure it has tidied up
incomplete_file_path = os.path.join(self.cache_dir,
'incomplete', image_id)
invalid_file_path = os.path.join(self.cache_dir, 'invalid', image_id)
self.assertFalse(os.path.exists(incomplete_file_path))
self.assertTrue(os.path.exists(invalid_file_path))
[docs] def test_gate_caching_iter_good_checksum(self):
image = b"12345678990abcdefghijklmnop"
image_id = 123
md5 = hashlib.md5()
md5.update(image)
checksum = md5.hexdigest()
cache = image_cache.ImageCache()
img_iter = cache.get_caching_iter(image_id, checksum, [image])
for chunk in img_iter:
pass
# checksum is valid, fake image should be cached:
self.assertTrue(cache.is_cached(image_id))
[docs] def test_gate_caching_iter_bad_checksum(self):
image = b"12345678990abcdefghijklmnop"
image_id = 123
checksum = "foobar" # bad.
cache = image_cache.ImageCache()
img_iter = cache.get_caching_iter(image_id, checksum, [image])
def reader():
for chunk in img_iter:
pass
self.assertRaises(exception.GlanceException, reader)
# checksum is invalid, caching will fail:
self.assertFalse(cache.is_cached(image_id))
[docs]class TestImageCacheXattr(test_utils.BaseTestCase,
ImageCacheTestCase):
"""Tests image caching when xattr is used in cache"""
[docs] def setUp(self):
"""
Test to see if the pre-requisites for the image cache
are working (python-xattr installed and xattr support on the
filesystem)
"""
super(TestImageCacheXattr, self).setUp()
if getattr(self, 'disable', False):
return
self.cache_dir = self.useFixture(fixtures.TempDir()).path
if not getattr(self, 'inited', False):
try:
import xattr # noqa
except ImportError:
self.inited = True
self.disabled = True
self.disabled_message = ("python-xattr not installed.")
return
self.inited = True
self.disabled = False
self.config(image_cache_dir=self.cache_dir,
image_cache_driver='xattr',
image_cache_max_size=5 * units.Ki)
self.cache = image_cache.ImageCache()
if not xattr_writes_supported(self.cache_dir):
self.inited = True
self.disabled = True
self.disabled_message = ("filesystem does not support xattr")
return
[docs]class TestImageCacheSqlite(test_utils.BaseTestCase,
ImageCacheTestCase):
"""Tests image caching when SQLite is used in cache"""
[docs] def setUp(self):
"""
Test to see if the pre-requisites for the image cache
are working (python-sqlite3 installed)
"""
super(TestImageCacheSqlite, self).setUp()
if getattr(self, 'disable', False):
return
if not getattr(self, 'inited', False):
try:
import sqlite3 # noqa
except ImportError:
self.inited = True
self.disabled = True
self.disabled_message = ("python-sqlite3 not installed.")
return
self.inited = True
self.disabled = False
self.cache_dir = self.useFixture(fixtures.TempDir()).path
self.config(image_cache_dir=self.cache_dir,
image_cache_driver='sqlite',
image_cache_max_size=5 * units.Ki)
self.cache = image_cache.ImageCache()
[docs]class TestImageCacheNoDep(test_utils.BaseTestCase):
[docs] def setUp(self):
super(TestImageCacheNoDep, self).setUp()
self.driver = None
def init_driver(self2):
self2.driver = self.driver
mox_fixture = self.useFixture(moxstubout.MoxStubout())
self.stubs = mox_fixture.stubs
self.stubs.Set(image_cache.ImageCache, 'init_driver', init_driver)
[docs] def test_get_caching_iter_when_write_fails(self):
class FailingFile(object):
def write(self, data):
if data == "Fail":
raise IOError
class FailingFileDriver(object):
def is_cacheable(self, *args, **kwargs):
return True
@contextmanager
def open_for_write(self, *args, **kwargs):
yield FailingFile()
self.driver = FailingFileDriver()
cache = image_cache.ImageCache()
data = [b'a', b'b', b'c', b'Fail', b'd', b'e', b'f']
caching_iter = cache.get_caching_iter('dummy_id', None, iter(data))
self.assertEqual(data, list(caching_iter))
[docs] def test_get_caching_iter_when_open_fails(self):
class OpenFailingDriver(object):
def is_cacheable(self, *args, **kwargs):
return True
@contextmanager
def open_for_write(self, *args, **kwargs):
raise IOError
self.driver = OpenFailingDriver()
cache = image_cache.ImageCache()
data = [b'a', b'b', b'c', b'd', b'e', b'f']
caching_iter = cache.get_caching_iter('dummy_id', None, iter(data))
self.assertEqual(data, list(caching_iter))