openstack/horizon
Code Issues Proposed changes

Fix web-server memory overrun when downloading objects from Swift

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To prevent memory overrun when downloading large objects from Swift
* `resp_chunk_size` keyword should be passed to swiftclient
* `obj.data` iterator returned from swiftclient is passed to HttpResponse
  (or StreamingHttpResponse for Django>=1.5) as usual since both response
  classes work with iterators/files/byte strings (yet StreamingHttpResponse
  does it better).

The commit introduces new setting SWIFT_FILE_TRANSFER_CHUNK_SIZE that
defines the size of chunk in bytes for Swift objects downloading.

DocImpact

Change-Id: I18e5809b86bfa24948dc642da2a55dffaa1a4ce1
Closes-Bug: #1427819
This commit is contained in:
Timur Sufiev 2015-03-04 16:15:04 +03:00
parent 36e87c6b75
commit 46405d456d
7 changed files with 120 additions and 18 deletions
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13
doc/source/topics/settings.rst
View File

@ -335,6 +335,19 @@ Valid values are ``"AUTO"``(default), ``"VNC"``, ``"SPICE"``, ``"RDP"``,
``"SERIAL"`` is available since 2005.1(Kilo).
``SWIFT_FILE_TRANSFER_CHUNK_SIZE``
----------------------------------
.. versionadded:: 2015.1(Kilo)
Default: ``512 * 1024``
This setting specifies the size of the chunk (in bytes) for downloading objects
from Swift. Do not make it very large (higher than several dozens of Megabytes,
exact number depends on your connection speed), otherwise you may encounter
socket timeout. The default value is 524288 bytes (or 512 Kilobytes).
``INSTANCE_LOG_LENGTH``
-----------------------

43
horizon/test/helpers.py
View File

@ -31,6 +31,7 @@ from django.core.handlers import wsgi
from django import http
from django import test as django_test
from django.test.client import RequestFactory # noqa
from django.test import testcases
from django.utils.encoding import force_text
from django.utils import unittest
@ -208,6 +209,48 @@ class TestCase(django_test.TestCase):
"%s messages not as expected: %s" % (msg_type.title(),
", ".join(msgs))
def assertNotContains(self, response, text, status_code=200,
msg_prefix='', html=False):
"""Asserts that a response indicates that some content was retrieved
successfully, (i.e., the HTTP status code was as expected), and that
``text`` doesn't occurs in the content of the response.
This is an override of django_test.TestCase.assertNotContains method,
which is able to work with StreamingHttpResponse.
"""
# If the response supports deferred rendering and hasn't been rendered
# yet, then ensure that it does get rendered before proceeding further.
if (hasattr(response, 'render') and callable(response.render) and
not response.is_rendered):
response.render()
if msg_prefix:
msg_prefix += ": "
self.assertEqual(
response.status_code, status_code,
msg_prefix + "Couldn't retrieve content: Response code was %d"
" (expected %d)" % (response.status_code, status_code))
if getattr(response, 'streaming', False):
content = b''.join(response.streaming_content)
else:
content = response.content
if not isinstance(text, bytes) or html:
text = force_text(text, encoding=response._charset)
content = content.decode(response._charset)
text_repr = "'%s'" % text
else:
text_repr = repr(text)
if html:
content = testcases.assert_and_parse_html(
self, content, None, 'Response\'s content is not valid HTML:')
text = testcases.assert_and_parse_html(
self, text, None, 'Second argument is not valid HTML:')
self.assertEqual(
content.count(text), 0,
msg_prefix + "Response should not contain %s" % text_repr)
@unittest.skipUnless(os.environ.get('WITH_SELENIUM', False),
"The WITH_SELENIUM env variable is not set.")

8
openstack_dashboard/api/swift.py
View File

@ -33,6 +33,7 @@ from openstack_dashboard.api import base
LOG = logging.getLogger(__name__)
FOLDER_DELIMITER = "/"
CHUNK_SIZE = getattr(settings, 'SWIFT_FILE_TRANSFER_CHUNK_SIZE', 512 * 1024)
# Swift ACL
GLOBAL_READ_ACL = ".r:*"
LIST_CONTENTS_ACL = ".rlistings"
@ -326,10 +327,11 @@ def swift_delete_object(request, container_name, object_name):
return True
def swift_get_object(request, container_name, object_name, with_data=True):
def swift_get_object(request, container_name, object_name, with_data=True,
resp_chunk_size=CHUNK_SIZE):
if with_data:
headers, data = swift_api(request).get_object(container_name,
object_name)
headers, data = swift_api(request).get_object(
container_name, object_name, resp_chunk_size=resp_chunk_size)
else:
data = None
headers = swift_api(request).head_object(container_name,

29
openstack_dashboard/dashboards/project/containers/tests.py
View File

@ -16,8 +16,10 @@
# License for the specific language governing permissions and limitations
# under the License.
import copy
import tempfile
import django
from django.core.files.uploadedfile import InMemoryUploadedFile # noqa
from django import http
from django.utils import http as utils_http
@ -337,19 +339,34 @@ class SwiftTests(test.TestCase):
for container in self.containers.list():
for obj in self.objects.list():
self.mox.ResetAll() # mandatory in a for loop
api.swift.swift_get_object(IsA(http.HttpRequest),
container.name,
obj.name).AndReturn(obj)
obj = copy.copy(obj)
_data = obj.data
def make_iter():
yield _data
obj.data = make_iter()
api.swift.swift_get_object(
IsA(http.HttpRequest),
container.name,
obj.name,
resp_chunk_size=api.swift.CHUNK_SIZE).AndReturn(obj)
self.mox.ReplayAll()
download_url = reverse(
'horizon:project:containers:object_download',
args=[container.name, obj.name])
res = self.client.get(download_url)
self.assertEqual(res.content, obj.data)
self.assertTrue(res.has_header('Content-Disposition'))
self.assertNotContains(res, INVALID_CONTAINER_NAME_1)
self.assertNotContains(res, INVALID_CONTAINER_NAME_2)
if django.VERSION >= (1, 5):
self.assertEqual(b''.join(res.streaming_content), _data)
self.assertNotContains(res, INVALID_CONTAINER_NAME_1)
self.assertNotContains(res, INVALID_CONTAINER_NAME_2)
else:
self.assertEqual(res.content, _data)
self.assertNotContains(res, INVALID_CONTAINER_NAME_1)
self.assertNotContains(res, INVALID_CONTAINER_NAME_2)
# Check that the returned Content-Disposition filename is well
# surrounded by double quotes and with commas removed

15
openstack_dashboard/dashboards/project/containers/views.py
View File

@ -22,6 +22,7 @@ Views for managing Swift containers.
import os
import django
from django import http
from django.utils.functional import cached_property # noqa
from django.utils.translation import ugettext_lazy as _
@ -193,7 +194,8 @@ class UploadView(forms.ModalFormView):
def object_download(request, container_name, object_path):
try:
obj = api.swift.swift_get_object(request, container_name, object_path)
obj = api.swift.swift_get_object(request, container_name, object_path,
resp_chunk_size=swift.CHUNK_SIZE)
except Exception:
redirect = reverse("horizon:project:containers:index")
exceptions.handle(request,
@ -205,11 +207,18 @@ def object_download(request, container_name, object_path):
if not os.path.splitext(obj.name)[1] and obj.orig_name:
name, ext = os.path.splitext(obj.orig_name)
filename = "%s%s" % (filename, ext)
response = http.HttpResponse()
# NOTE(tsufiev): StreamingHttpResponse class had been introduced in
# Django 1.5 specifically for the purpose streaming and/or transferring
# large files, it's less fragile than standard HttpResponse and should be
# used when available.
if django.VERSION >= (1, 5):
response = http.StreamingHttpResponse(obj.data)
else:
response = http.HttpResponse(obj.data)
safe_name = filename.replace(",", "").encode('utf-8')
response['Content-Disposition'] = 'attachment; filename="%s"' % safe_name
response['Content-Type'] = 'application/octet-stream'
response.write(obj.data)
response['Content-Length'] = obj.bytes
return response

3
openstack_dashboard/local/local_settings.py.example
View File

@ -256,6 +256,9 @@ IMAGE_RESERVED_CUSTOM_PROPERTIES = []
API_RESULT_LIMIT = 1000
API_RESULT_PAGE_SIZE = 20
# The size of chunk in bytes for downloading objects from Swift
SWIFT_FILE_TRANSFER_CHUNK_SIZE = 512 * 1024
# Specify a maximum number of items to display in a dropdown.
DROPDOWN_MAX_ITEMS = 30

27
openstack_dashboard/test/api_tests/swift_tests.py
View File

@ -123,19 +123,34 @@ class SwiftApiTests(test.APITestCase):
self.assertEqual(len(objects), len(objs))
self.assertFalse(more)
def test_swift_get_object_with_data(self):
def test_swift_get_object_with_data_non_chunked(self):
container = self.containers.first()
object = self.objects.first()
swift_api = self.stub_swiftclient()
swift_api.get_object(container.name, object.name) \
.AndReturn([object, object.data])
swift_api.get_object(
container.name, object.name, resp_chunk_size=None
).AndReturn([object, object.data])
self.mox.ReplayAll()
obj = api.swift.swift_get_object(self.request,
container.name,
object.name)
obj = api.swift.swift_get_object(self.request, container.name,
object.name, resp_chunk_size=None)
self.assertEqual(object.name, obj.name)
def test_swift_get_object_with_data_chunked(self):
container = self.containers.first()
object = self.objects.first()
swift_api = self.stub_swiftclient()
swift_api.get_object(
container.name, object.name, resp_chunk_size=api.swift.CHUNK_SIZE
).AndReturn([object, object.data])
self.mox.ReplayAll()
obj = api.swift.swift_get_object(
self.request, container.name, object.name)
self.assertEqual(object.name, obj.name)
def test_swift_get_object_without_data(self):