From acab9351a1fa124f2bdeb58d2f407070071dc9d2 Mon Sep 17 00:00:00 2001
From: Takashi Kajinami <kajinamit@oss.nttdata.com>
Date: Sun, 22 Sep 2024 21:35:34 +0900
Subject: [PATCH] Remove Windows OS support

Windows OS support was deprecated in 2024.1 cycle because Winstackers
project was retired[1]. Remove the support now to get rid of os-win
which was also abandoned.

[1] a8bed388f26eb383449b4d040c4da84671587fb9

Change-Id: I737279c93a6231ebf2e8c87810040ce48622f4fc
---
 doc/source/admin/requirements.rst             |   4 -
 doc/source/configuration/configuring.rst      |   3 +-
 glance/cmd/api.py                             |   9 +-
 glance/cmd/scrubber.py                        |  32 +---
 glance/common/wsgi.py                         | 139 +-----------------
 glance/opts.py                                |   1 -
 glance/tests/__init__.py                      |   9 +-
 glance/tests/functional/__init__.py           |  83 +----------
 glance/tests/functional/db/base.py            |   6 -
 .../drivers/test_centralized_db.py            |   1 -
 glance/tests/functional/test_logging.py       |   6 -
 glance/tests/functional/test_wsgi.py          |  17 +--
 glance/tests/unit/common/test_wsgi.py         |   2 -
 glance/tests/unit/test_db.py                  |   3 -
 glance/tests/unit/test_image_cache.py         |   2 -
 glance/tests/utils.py                         |  33 +----
 .../remove-windows-873b19639c9b6ed5.yaml      |   5 +
 requirements.txt                              |   2 -
 18 files changed, 22 insertions(+), 335 deletions(-)
 create mode 100644 releasenotes/notes/remove-windows-873b19639c9b6ed5.yaml

diff --git a/doc/source/admin/requirements.rst b/doc/source/admin/requirements.rst
index 87701e2c7f..30c5878cdc 100644
--- a/doc/source/admin/requirements.rst
+++ b/doc/source/admin/requirements.rst
@@ -26,10 +26,6 @@ of its features. Some examples include the ``qemu-img`` utility used by the
 tasks feature, ``pydev`` to debug using popular IDEs, ``python-xattr`` for
 Image Cache using "xattr" driver.
 
-Additionally, some libraries like ``xattr`` are not compatible when
-using Glance on Windows (see :ref:`the documentation on config options
-affecting the Image Cache <configuring>`).
-
 
 Guideline to include your requirement in the requirements.txt file
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/doc/source/configuration/configuring.rst b/doc/source/configuration/configuring.rst
index 34ff33c02f..c3159dd118 100644
--- a/doc/source/configuration/configuring.rst
+++ b/doc/source/configuration/configuring.rst
@@ -1756,8 +1756,7 @@ One main configuration file option affects the image cache.
   and requires that the filesystem containing ``image_cache_dir`` have
   access times tracked for all files (in other words, the noatime option
   CANNOT be set for that filesystem). In addition, ``user_xattr`` must be
-  set on the filesystem's description line in fstab. Because of these
-  requirements, the ``xattr`` cache driver is not available on Windows.
+  set on the filesystem's description line in fstab.
 
 ``image_cache_sqlite_db=DB_FILE``
   Optional.
diff --git a/glance/cmd/api.py b/glance/cmd/api.py
index 7cc3a61a66..abeaeb663f 100644
--- a/glance/cmd/api.py
+++ b/glance/cmd/api.py
@@ -25,13 +25,7 @@ import os
 import sys
 
 import eventlet
-
-if os.name == 'nt':
-    # eventlet monkey patching the os module causes subprocess.Popen to fail
-    # on Windows when using pipes due to missing non-blocking IO support.
-    eventlet.patcher.monkey_patch(os=False)
-else:
-    eventlet.patcher.monkey_patch()
+eventlet.patcher.monkey_patch()
 
 # Monkey patch the original current_thread to use the up-to-date _active
 # global variable. See https://bugs.launchpad.net/bugs/1863021 and
@@ -66,7 +60,6 @@ from glance import version
 CONF = cfg.CONF
 CONF.import_group("profiler", "glance.common.wsgi")
 logging.register_options(CONF)
-wsgi.register_cli_opts()
 
 # NOTE(rosmaita): Any new exceptions added should preserve the current
 # error codes for backward compatibility.  The value 99 is returned
diff --git a/glance/cmd/scrubber.py b/glance/cmd/scrubber.py
index 09e1928066..be64e105e7 100644
--- a/glance/cmd/scrubber.py
+++ b/glance/cmd/scrubber.py
@@ -23,13 +23,7 @@ import os
 import sys
 
 import eventlet
-
-if os.name == 'nt':
-    # eventlet monkey patching the os module causes subprocess.Popen to fail
-    # on Windows when using pipes due to missing non-blocking IO support.
-    eventlet.patcher.monkey_patch(os=False)
-else:
-    eventlet.patcher.monkey_patch()
+eventlet.patcher.monkey_patch()
 
 # Monkey patch the original current_thread to use the up-to-date _active
 # global variable. See https://bugs.launchpad.net/bugs/1863021 and
@@ -49,7 +43,6 @@ if os.path.exists(os.path.join(possible_topdir, 'glance', '__init__.py')):
     sys.path.insert(0, possible_topdir)
 
 import glance_store
-from os_win import utilsfactory as os_win_utilsfactory
 from oslo_config import cfg
 from oslo_log import log as logging
 
@@ -64,18 +57,7 @@ CONF.set_default(name='use_stderr', default=True)
 
 
 def main():
-    # Used on Window, ensuring that a single scrubber can run at a time.
-    mutex = None
-    mutex_acquired = False
-
     try:
-        if os.name == 'nt':
-            # We can't rely on process names on Windows as there may be
-            # wrappers with the same name.
-            mutex = os_win_utilsfactory.get_mutex(
-                name='Global\\glance-scrubber')
-            mutex_acquired = mutex.acquire(timeout_ms=0)
-
         CONF.register_cli_opts(scrubber.scrubber_cmd_cli_opts)
         CONF.register_opts(scrubber.scrubber_cmd_opts)
 
@@ -99,12 +81,7 @@ def main():
         app = scrubber.Scrubber(glance_store)
 
         if CONF.restore:
-            if os.name == 'nt':
-                scrubber_already_running = not mutex_acquired
-            else:
-                scrubber_already_running = scrubber_already_running_posix()
-
-            if scrubber_already_running:
+            if scrubber_already_running():
                 already_running_msg = (
                     "ERROR: glance-scrubber is already running. "
                     "Please ensure that the daemon is stopped.")
@@ -121,12 +98,9 @@ def main():
         sys.exit("ERROR: %s" % e)
     except RuntimeError as e:
         sys.exit("ERROR: %s" % e)
-    finally:
-        if mutex and mutex_acquired:
-            mutex.release()
 
 
-def scrubber_already_running_posix():
+def scrubber_already_running():
     # Try to check the glance-scrubber is running or not.
     # 1. Try to find the pid file if scrubber is controlled by
     #    glance-control
diff --git a/glance/common/wsgi.py b/glance/common/wsgi.py
index 21e42bbfa9..80ec4bd069 100644
--- a/glance/common/wsgi.py
+++ b/glance/common/wsgi.py
@@ -24,10 +24,7 @@ import abc
 import errno
 import functools
 import os
-import re
 import signal
-import struct
-import subprocess
 import sys
 import time
 
@@ -35,7 +32,6 @@ from eventlet.green import socket
 import eventlet.greenio
 import eventlet.wsgi
 import glance_store
-from os_win import utilsfactory as os_win_utilsfactory
 from oslo_concurrency import processutils
 from oslo_config import cfg
 from oslo_log import log as logging
@@ -252,13 +248,6 @@ store_opts = [
                        'using comma.')),
 ]
 
-cli_opts = [
-    cfg.StrOpt('pipe-handle',
-               help='This argument is used internally on Windows. Glance '
-                    'passes a pipe handle to child processes, which is then '
-                    'used for inter-process communication.'),
-]
-
 
 LOG = logging.getLogger(__name__)
 
@@ -286,17 +275,9 @@ RESERVED_STORES = {
 }
 
 
-def register_cli_opts():
-    CONF.register_cli_opts(cli_opts)
-
-
 def get_num_workers():
     """Return the configured number of workers."""
 
-    # Windows only: we're already running on the worker side.
-    if os.name == 'nt' and getattr(CONF, 'pipe_handle', None):
-        return 0
-
     if CONF.workers is None:
         # None implies the number of CPUs limited to 8
         # See Launchpad bug #1748916 and the config help text
@@ -740,125 +721,7 @@ class PosixServer(BaseServer):
         self.start_wsgi()
 
 
-class Win32ProcessLauncher(object):
-    def __init__(self):
-        self._processutils = os_win_utilsfactory.get_processutils()
-
-        self._workers = []
-        self._worker_job_handles = []
-
-    def add_process(self, cmd):
-        LOG.info("Starting subprocess: %s", cmd)
-
-        worker = subprocess.Popen(cmd, close_fds=False)
-        try:
-            job_handle = self._processutils.kill_process_on_job_close(
-                worker.pid)
-        except Exception:
-            LOG.exception("Could not associate child process "
-                          "with a job, killing it.")
-            worker.kill()
-            raise
-
-        self._worker_job_handles.append(job_handle)
-        self._workers.append(worker)
-
-        return worker
-
-    def wait(self):
-        pids = [worker.pid for worker in self._workers]
-        if pids:
-            self._processutils.wait_for_multiple_processes(pids,
-                                                           wait_all=True)
-        # By sleeping here, we allow signal handlers to be executed.
-        time.sleep(0)
-
-
-class Win32Server(BaseServer):
-    _py_script_re = re.compile(r'.*\.py\w?$')
-    _sock = None
-
-    def __init__(self, *args, **kwargs):
-        LOG.warning("Support for Glance on Windows operating systems is"
-                    "deprecated.")
-        super(Win32Server, self).__init__(*args, **kwargs)
-        self._launcher = Win32ProcessLauncher()
-        self._ioutils = os_win_utilsfactory.get_ioutils()
-
-    def run_child(self):
-        # We're passing copies of the socket through pipes.
-        rfd, wfd = self._ioutils.create_pipe(inherit_handle=True)
-
-        cmd = sys.argv + ['--pipe-handle=%s' % int(rfd)]
-        # Recent setuptools versions will trim '-script.py' and '.exe'
-        # extensions from sys.argv[0].
-        if self._py_script_re.match(sys.argv[0]):
-            cmd = [sys.executable] + cmd
-
-        worker = self._launcher.add_process(cmd)
-        self._ioutils.close_handle(rfd)
-
-        share_sock_buff = self._sock.share(worker.pid)
-        self._ioutils.write_file(
-            wfd,
-            struct.pack('<I', len(share_sock_buff)),
-            4)
-        self._ioutils.write_file(
-            wfd, share_sock_buff, len(share_sock_buff))
-
-        self.children.add(worker.pid)
-
-    def kill_children(self, *args):
-        # We're using job objects, the children will exit along with the
-        # main process.
-        exit(0)
-
-    def wait_on_children(self):
-        self._launcher.wait()
-
-    def _get_sock_from_parent(self):
-        # This is supposed to be called exactly once in the child process.
-        # We're passing a copy of the socket through a pipe.
-        pipe_handle = int(getattr(CONF, 'pipe_handle', 0))
-        if not pipe_handle:
-            err_msg = _("Did not receive a pipe handle, which is used when "
-                        "communicating with the parent process.")
-            raise exception.GlanceException(err_msg)
-
-        # Get the length of the data to be received.
-        buff = self._ioutils.get_buffer(4)
-        self._ioutils.read_file(pipe_handle, buff, 4)
-        socket_buff_sz = struct.unpack('<I', buff)[0]
-
-        # Get the serialized socket object.
-        socket_buff = self._ioutils.get_buffer(socket_buff_sz)
-        self._ioutils.read_file(pipe_handle, socket_buff, socket_buff_sz)
-        self._ioutils.close_handle(pipe_handle)
-
-        # Recreate the socket object. This will only work with
-        # Python 3.6 or later.
-        return socket.fromshare(bytes(socket_buff[:]))
-
-    def configure_socket(self, old_conf=None, has_changed=None):
-        fresh_start = not (old_conf or has_changed)
-        pipe_handle = getattr(CONF, 'pipe_handle', None)
-
-        if not (fresh_start and pipe_handle):
-            return super(Win32Server, self).configure_socket(
-                old_conf, has_changed)
-
-        self.sock = self._get_sock_from_parent()
-
-        if hasattr(socket, 'TCP_KEEPIDLE'):
-            # This was introduced in WS 2016 RS3
-            self.sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPIDLE,
-                                 CONF.tcp_keepidle)
-
-
-if os.name == 'nt':
-    Server = Win32Server
-else:
-    Server = PosixServer
+Server = PosixServer
 
 
 class Middleware(object):
diff --git a/glance/opts.py b/glance/opts.py
index ecf74e46f8..dc736f8ab7 100644
--- a/glance/opts.py
+++ b/glance/opts.py
@@ -51,7 +51,6 @@ _api_opts = [
         glance.common.wsgi.eventlet_opts,
         glance.common.wsgi.socket_opts,
         glance.common.wsgi.store_opts,
-        glance.common.wsgi.cli_opts,
         glance.image_cache.drivers.sqlite.sqlite_opts,
         glance.image_cache.image_cache_opts,
         glance.notifier.notifier_opts,
diff --git a/glance/tests/__init__.py b/glance/tests/__init__.py
index 4a4d3320e4..9d3ba55934 100644
--- a/glance/tests/__init__.py
+++ b/glance/tests/__init__.py
@@ -14,16 +14,9 @@
 #    under the License.
 
 import builtins
-import os
 
 import eventlet
-
-if os.name == 'nt':
-    # eventlet monkey patching the os module causes subprocess.Popen to fail
-    # on Windows when using pipes due to missing non-blocking IO support.
-    eventlet.patcher.monkey_patch(os=False)
-else:
-    eventlet.patcher.monkey_patch()
+eventlet.patcher.monkey_patch()
 
 import glance.async_
 # NOTE(danms): Default to eventlet threading for tests
diff --git a/glance/tests/functional/__init__.py b/glance/tests/functional/__init__.py
index a0e321d9db..b91b454688 100644
--- a/glance/tests/functional/__init__.py
+++ b/glance/tests/functional/__init__.py
@@ -30,7 +30,6 @@ import platform
 import shutil
 import signal
 import socket
-import subprocess
 import sys
 import tempfile
 from testtools import content as ttc
@@ -42,7 +41,6 @@ import uuid
 
 import fixtures
 import glance_store
-from os_win import utilsfactory as os_win_utilsfactory
 from oslo_config import cfg
 from oslo_serialization import jsonutils
 import testtools
@@ -58,12 +56,7 @@ from glance.tests import utils as test_utils
 execute, get_unused_port = test_utils.execute, test_utils.get_unused_port
 tracecmd_osmap = {'Linux': 'strace', 'FreeBSD': 'truss'}
 
-if os.name == 'nt':
-    SQLITE_CONN_TEMPLATE = 'sqlite:///%s/tests.sqlite'
-else:
-    SQLITE_CONN_TEMPLATE = 'sqlite:////%s/tests.sqlite'
-
-
+SQLITE_CONN_TEMPLATE = 'sqlite:////%s/tests.sqlite'
 CONF = cfg.CONF
 
 
@@ -301,79 +294,7 @@ class PosixServer(BaseServer):
         return (rc, '', '')
 
 
-class Win32Server(BaseServer):
-    def __init__(self, *args, **kwargs):
-        super(Win32Server, self).__init__(*args, **kwargs)
-
-        self._processutils = os_win_utilsfactory.get_processutils()
-
-    def start(self, expect_exit=True, expected_exitcode=0, **kwargs):
-        """
-        Starts the server.
-
-        Any kwargs passed to this method will override the configuration
-        value in the conf file used in starting the servers.
-        """
-
-        # Ensure the configuration file is written
-        self.write_conf(**kwargs)
-
-        self.create_database()
-
-        cmd = ("%(server_module)s --config-file %(conf_file_name)s"
-               % {"server_module": self.server_module,
-                  "conf_file_name": self.conf_file_name})
-        cmd = "%s -m %s" % (sys.executable, cmd)
-
-        # Passing socket objects on Windows is a bit more cumbersome.
-        # We don't really have to do it.
-        if self.sock:
-            self.sock.close()
-            self.sock = None
-
-        self.process = subprocess.Popen(
-            cmd,
-            env=self.exec_env)
-        self.process_pid = self.process.pid
-
-        try:
-            self.job_handle = self._processutils.kill_process_on_job_close(
-                self.process_pid)
-        except Exception:
-            # Could not associate child process with a job, killing it.
-            self.process.kill()
-            raise
-
-        self.stop_kill = not expect_exit
-        if self.pid_file:
-            pf = open(self.pid_file, 'w')
-            pf.write('%d\n' % self.process_pid)
-            pf.close()
-
-        rc = 0
-        if expect_exit:
-            self.process.communicate()
-            rc = self.process.returncode
-
-        return (rc, '', '')
-
-    def stop(self):
-        """
-        Spin down the server.
-        """
-        if not self.process_pid:
-            raise Exception('Server "%s" process not running.'
-                            % self.server_name)
-
-        if self.stop_kill:
-            self.process.terminate()
-        return (0, '', '')
-
-
-if os.name == 'nt':
-    Server = Win32Server
-else:
-    Server = PosixServer
+Server = PosixServer
 
 
 class ApiServer(Server):
diff --git a/glance/tests/functional/db/base.py b/glance/tests/functional/db/base.py
index 733b491ee8..af3de7367a 100644
--- a/glance/tests/functional/db/base.py
+++ b/glance/tests/functional/db/base.py
@@ -137,7 +137,6 @@ class TestDriver(test_utils.BaseTestCase):
     def create_images(self, images):
         for fixture in images:
             self.db_api.image_create(self.adm_context, fixture)
-            self.delay_inaccurate_clock()
 
 
 class DriverTests(object):
@@ -318,7 +317,6 @@ class DriverTests(object):
 
     def test_image_update_properties(self):
         fixture = {'properties': {'ping': 'pong'}}
-        self.delay_inaccurate_clock()
         image = self.db_api.image_update(self.adm_context, UUID1, fixture)
         expected = {'ping': 'pong', 'foo': 'bar', 'far': 'boo'}
         actual = {p['name']: p['value'] for p in image['properties']}
@@ -1294,7 +1292,6 @@ class DriverTests(object):
                     'deleted': False}
         self.assertEqual(expected, member)
 
-        self.delay_inaccurate_clock()
         member = self.db_api.image_member_update(self.context,
                                                  member_id,
                                                  {'can_share': True})
@@ -1338,7 +1335,6 @@ class DriverTests(object):
                     'deleted': False}
         self.assertEqual(expected, member)
 
-        self.delay_inaccurate_clock()
         member = self.db_api.image_member_update(self.context,
                                                  member_id,
                                                  {'status': 'accepted'})
@@ -1947,7 +1943,6 @@ class TaskTests(test_utils.BaseTestCase):
             'status': 'processing',
             'message': 'This is a error string',
         }
-        self.delay_inaccurate_clock()
         task = self.db_api.task_update(self.adm_context, task_id, fixture)
 
         self.assertEqual(task_id, task['id'])
@@ -1973,7 +1968,6 @@ class TaskTests(test_utils.BaseTestCase):
 
         task_id = task['id']
         fixture = {'status': 'processing'}
-        self.delay_inaccurate_clock()
         task = self.db_api.task_update(self.adm_context, task_id, fixture)
 
         self.assertEqual(task_id, task['id'])
diff --git a/glance/tests/functional/image_cache/drivers/test_centralized_db.py b/glance/tests/functional/image_cache/drivers/test_centralized_db.py
index a273aff8f8..d0a9dadd75 100644
--- a/glance/tests/functional/image_cache/drivers/test_centralized_db.py
+++ b/glance/tests/functional/image_cache/drivers/test_centralized_db.py
@@ -351,7 +351,6 @@ class TestCentralizedDb(functional.SynchronousAPIBase):
 
         self.assertTrue(os.path.exists(incomplete_file_path))
 
-        self.delay_inaccurate_clock()
         self.driver.clean(stall_time=0)
 
         self.assertFalse(os.path.exists(incomplete_file_path))
diff --git a/glance/tests/functional/test_logging.py b/glance/tests/functional/test_logging.py
index 5879e698ed..dce377cb27 100644
--- a/glance/tests/functional/test_logging.py
+++ b/glance/tests/functional/test_logging.py
@@ -70,12 +70,6 @@ class TestLogging(functional.FunctionalTest):
         """
         Test that we notice when our log file has been rotated
         """
-
-        # Moving in-use files is not supported on Windows.
-        # The log handler itself may be configured to rotate files.
-        if os.name == 'nt':
-            raise self.skipException("Unsupported platform.")
-
         self.cleanup()
         self.start_servers()
 
diff --git a/glance/tests/functional/test_wsgi.py b/glance/tests/functional/test_wsgi.py
index 76aedcb205..14f2cc041a 100644
--- a/glance/tests/functional/test_wsgi.py
+++ b/glance/tests/functional/test_wsgi.py
@@ -45,18 +45,11 @@ class TestWSGIServer(functional.FunctionalTest):
         port = server.sock.getsockname()[1]
 
         def get_request(delay=0.0):
-            # Socket timeouts are handled rather inconsistently on Windows.
-            # recv may either return nothing OR raise a ConnectionAbortedError.
-            exp_exc = OSError if os.name == 'nt' else ()
-
-            try:
-                sock = socket.socket()
-                sock.connect(('127.0.0.1', port))
-                time.sleep(delay)
-                sock.send(b'GET / HTTP/1.1\r\nHost: localhost\r\n\r\n')
-                return sock.recv(1024)
-            except exp_exc:
-                return None
+            sock = socket.socket()
+            sock.connect(('127.0.0.1', port))
+            time.sleep(delay)
+            sock.send(b'GET / HTTP/1.1\r\nHost: localhost\r\n\r\n')
+            return sock.recv(1024)
 
         # Should succeed - no timeout
         self.assertIn(greetings, get_request())
diff --git a/glance/tests/unit/common/test_wsgi.py b/glance/tests/unit/common/test_wsgi.py
index 54d4a89237..020e222218 100644
--- a/glance/tests/unit/common/test_wsgi.py
+++ b/glance/tests/unit/common/test_wsgi.py
@@ -606,8 +606,6 @@ class ServerTest(test_utils.BaseTestCase):
     def test_number_of_workers_posix(self, mock_migrate_db, mock_prefetcher):
         """Ensure the number of workers matches num cpus limited to 8."""
         mock_migrate_db.return_value = False
-        if os.name == 'nt':
-            raise self.skipException("Unsupported platform.")
 
         def pid():
             i = 1
diff --git a/glance/tests/unit/test_db.py b/glance/tests/unit/test_db.py
index 7d75ce9cb3..2bac5e4747 100644
--- a/glance/tests/unit/test_db.py
+++ b/glance/tests/unit/test_db.py
@@ -578,7 +578,6 @@ class TestImageRepo(test_utils.BaseTestCase):
         original_update_time = image.updated_at
         image.name = 'foo'
         image.tags = ['king', 'kong']
-        self.delay_inaccurate_clock()
         self.image_repo.save(image)
         current_update_time = image.updated_at
         self.assertGreater(current_update_time, original_update_time)
@@ -636,7 +635,6 @@ class TestImageRepo(test_utils.BaseTestCase):
     def test_remove_image(self):
         image = self.image_repo.get(UUID1)
         previous_update_time = image.updated_at
-        self.delay_inaccurate_clock()
         self.image_repo.remove(image)
         self.assertGreater(image.updated_at, previous_update_time)
         self.assertRaises(exception.ImageNotFound, self.image_repo.get, UUID1)
@@ -1053,7 +1051,6 @@ class TestTaskRepo(test_utils.BaseTestCase):
     def test_save_task(self):
         task = self.task_repo.get(UUID1)
         original_update_time = task.updated_at
-        self.delay_inaccurate_clock()
         self.task_repo.save(task)
         current_update_time = task.updated_at
         self.assertGreater(current_update_time, original_update_time)
diff --git a/glance/tests/unit/test_image_cache.py b/glance/tests/unit/test_image_cache.py
index e6e9566646..750760bead 100644
--- a/glance/tests/unit/test_image_cache.py
+++ b/glance/tests/unit/test_image_cache.py
@@ -139,7 +139,6 @@ class ImageCacheTestCase(object):
 
         self.assertTrue(os.path.exists(invalid_file_path))
 
-        self.delay_inaccurate_clock()
         if failure:
             with mock.patch.object(
                     fileutils, 'delete_if_exists') as mock_delete:
@@ -167,7 +166,6 @@ class ImageCacheTestCase(object):
 
         self.assertTrue(os.path.exists(incomplete_file_path))
 
-        self.delay_inaccurate_clock()
         self.cache.clean(stall_time=0)
 
         self.assertFalse(os.path.exists(incomplete_file_path))
diff --git a/glance/tests/utils.py b/glance/tests/utils.py
index dafe0cf0fe..2717c62b10 100644
--- a/glance/tests/utils.py
+++ b/glance/tests/utils.py
@@ -161,26 +161,6 @@ class BaseTestCase(testtools.TestCase):
         self.addCleanup(patcher.stop)
         return result
 
-    def delay_inaccurate_clock(self, duration=0.001):
-        """Add a small delay to compensate for inaccurate system clocks.
-
-        Some tests make assertions based on timestamps (e.g. comparing
-        'created_at' and 'updated_at' fields). In some cases, subsequent
-        time.time() calls may return identical values (python timestamps can
-        have a lower resolution on Windows compared to Linux - 1e-7 as
-        opposed to 1e-9).
-
-        A small delay (a few ms should be negligeable) can prevent such
-        issues. At the same time, it spares us from mocking the time
-        module, which might be undesired.
-        """
-
-        # For now, we'll do this only for Windows. If really needed,
-        # on Py3 we can get the clock resolution using time.get_clock_info,
-        # but at that point we may as well just sleep 1ms all the time.
-        if os.name == 'nt':
-            time.sleep(duration)
-
 
 class requires(object):
     """Decorator that initiates additional test setup/teardown."""
@@ -209,12 +189,8 @@ class depends_on_exe(object):
 
     def __call__(self, func):
         def _runner(*args, **kw):
-            if os.name != 'nt':
-                cmd = 'which %s' % self.exe
-            else:
-                cmd = 'where.exe', '%s' % self.exe
-
-            exitcode, out, err = execute(cmd, raise_error=False)
+            exitcode, out, err = execute('which %s' % self.exe,
+                                         raise_error=False)
             if exitcode != 0:
                 args[0].disabled_message = 'test requires exe: %s' % self.exe
                 args[0].disabled = True
@@ -394,10 +370,7 @@ def execute(cmd,
     path_ext = [os.path.join(os.getcwd(), 'bin')]
 
     # Also jack in the path cmd comes from, if it's absolute
-    if os.name != 'nt':
-        args = shlex.split(cmd)
-    else:
-        args = cmd
+    args = shlex.split(cmd)
 
     executable = args[0]
     if os.path.isabs(executable):
diff --git a/releasenotes/notes/remove-windows-873b19639c9b6ed5.yaml b/releasenotes/notes/remove-windows-873b19639c9b6ed5.yaml
new file mode 100644
index 0000000000..e4e233f132
--- /dev/null
+++ b/releasenotes/notes/remove-windows-873b19639c9b6ed5.yaml
@@ -0,0 +1,5 @@
+---
+upgrade:
+  - |
+    Support for running glance services in Windows operating systems has been
+    removed.
diff --git a/requirements.txt b/requirements.txt
index 114b9898c9..0a1c77fb27 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -51,6 +51,4 @@ cursive>=0.2.1 # Apache-2.0
 # timeutils
 iso8601>=0.1.11 # MIT
 
-os-win>=4.0.1 # Apache-2.0
-
 castellan>=0.17.0 # Apache-2.0