quobyte: remove dependency to xattr

The Quobyte driver introduced an new dependency to xattr
python binding. This driver is the only consumer of xattr.

Instead of introducing new dependencies call getfattr binary
as already done in the quobyte nova volume driver.

Closes-Bug: 1420332
Co-Authored-By: Marc Koderer <marc@koderer.com>

Change-Id: I83f97310313cf7a603996ae64327002cdf0ad5fc
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>

cinder/tests/test_quobyte.py

@@ -130,8 +130,7 @@ class QuobyteDriverTestCase(test.TestCase):
                 mock.patch.object(self._driver, '_execute'),
                 mock.patch('cinder.volume.drivers.quobyte.QuobyteDriver'
                            '.read_proc_mount'),
-                mock.patch('xattr.getxattr')
-        ) as (mock_execute, mock_open, mock_getxattr):
+        ) as (mock_execute, mock_open):
             # Content of /proc/mount (not mounted yet).
             mock_open.return_value = StringIO.StringIO(
                 "/dev/sda5 / ext4 rw,relatime,data=ordered 0 0")
@@ -144,31 +143,32 @@ class QuobyteDriverTestCase(test.TestCase):
             mount_call = mock.call(
                 'mount.quobyte', self.TEST_QUOBYTE_VOLUME,
                 self.TEST_MNT_POINT, run_as_root=False)
-            mock_execute.assert_has_calls([mkdir_call, mount_call],
-                                          any_order=False)
-            mock_getxattr.assert_called_once_with(self.TEST_MNT_POINT,
-                                                  'quobyte.info')
+
+            getfattr_call = mock.call(
+                'getfattr', '-n', 'quobyte.info', self.TEST_MNT_POINT,
+                run_as_root=False)
+
+            mock_execute.assert_has_calls(
+                [mkdir_call, mount_call, getfattr_call], any_order=False)
 
     def test_mount_quobyte_already_mounted_detected_seen_in_proc_mount(self):
         with contextlib.nested(
                 mock.patch.object(self._driver, '_execute'),
                 mock.patch('cinder.volume.drivers.quobyte.QuobyteDriver'
                            '.read_proc_mount'),
-                mock.patch('xattr.getxattr')
-        ) as (mock_execute, mock_open, mock_getxattr):
+        ) as (mock_execute, mock_open):
             # Content of /proc/mount (already mounted).
             mock_open.return_value = StringIO.StringIO(
                 "quobyte@%s %s fuse rw,nosuid,nodev,noatime,user_id=1000"
                 ",group_id=100,default_permissions,allow_other 0 0"
                 % (self.TEST_QUOBYTE_VOLUME, self.TEST_MNT_POINT))
-            mock_getxattr.return_value = "non-empty string"
 
             self._driver._mount_quobyte(self.TEST_QUOBYTE_VOLUME,
                                         self.TEST_MNT_POINT)
 
-            self.assertFalse(mock_execute.called)
-            mock_getxattr.assert_called_once_with(self.TEST_MNT_POINT,
-                                                  'quobyte.info')
+            mock_execute.assert_called_once_with(
+                'getfattr', '-n', 'quobyte.info', self.TEST_MNT_POINT,
+                run_as_root=False)
 
     def test_mount_quobyte_should_suppress_and_log_already_mounted_error(self):
         """Based on /proc/mount, the file system is not mounted yet. However,

cinder/volume/drivers/quobyte.py

@@ -19,11 +19,10 @@ import os
 
 from oslo_concurrency import processutils
 from oslo_config import cfg
-import xattr
 
 from cinder import compute
 from cinder import exception
-from cinder.i18n import _, _LE, _LI, _LW
+from cinder.i18n import _, _LI, _LW
 from cinder.image import image_utils
 from cinder.openstack.common import fileutils
 from cinder.openstack.common import log as logging
@@ -418,13 +417,19 @@ class QuobyteDriver(remotefs_drv.RemoteFSSnapDriver):
                     raise
 
         if mounted:
-            try:
-                xattr.getxattr(mount_path, 'quobyte.info')
-            except Exception as exc:
-                msg = _LE("The mount %(mount_path)s is not a valid"
-                          " Quobyte USP volume. Error: %(exc)s") \
-                    % {'mount_path': mount_path, 'exc': exc}
-                raise exception.VolumeDriverException(msg)
-            if not os.access(mount_path, os.W_OK | os.X_OK):
-                LOG.warn(_LW("Volume is not writable. Please broaden the file"
-                             " permissions. Mount: %s"), mount_path)
+            self._validate_volume(mount_path)
+
+    def _validate_volume(self, mount_path):
+        """Wraps execute calls for checking validity of a Quobyte volume"""
+        command = ['getfattr', "-n", "quobyte.info", mount_path]
+        try:
+            self._execute(*command, run_as_root=False)
+        except processutils.ProcessExecutionError as exc:
+            msg = (_("The mount %(mount_path)s is not a valid"
+                     " Quobyte USP volume. Error: %(exc)s")
+                   % {'mount_path': mount_path, 'exc': exc})
+            raise exception.VolumeDriverException(msg)
+
+        if not os.access(mount_path, os.W_OK | os.X_OK):
+            LOG.warn(_LW("Volume is not writable. Please broaden the file"
+                         " permissions. Mount: %s"), mount_path)

requirements.txt

@@ -44,4 +44,3 @@ WebOb>=1.2.3
 wsgiref>=0.1.2
 oslo.i18n>=1.3.0  # Apache-2.0
 oslo.vmware>=0.9.0                      # Apache-2.0
-xattr>=0.4