GlusterFS backup driver

This patch introduces GlusterFS storage as a backup target.
GlusterFS backup driver inherits from Posix backup driver[1].

[1] https://review.openstack.org/#/c/163647/

Implements: blueprint glusterfs-as-a-backup-driver
Change-Id: I4f0c36cdaa7cc417cb26bc1e908c6d107a71da35

diff --git a/cinder/backup/drivers/glusterfs.py b/cinder/backup/drivers/glusterfs.py
new file mode 100644 (file)
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+++ b/cinder/backup/drivers/glusterfs.py
@@ -0,0 +1,94 @@
+# Copyright (c) 2015 Red Hat, Inc.
+# 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.
+
+"""Implementation of a backup service that uses GlusterFS as the backend."""
+
+import os
+import stat
+
+from os_brick.remotefs import remotefs as remotefs_brick
+from oslo_concurrency import processutils as putils
+from oslo_config import cfg
+
+from cinder.backup.drivers import posix
+from cinder import exception
+from cinder import utils
+
+
+glusterfsbackup_service_opts = [
+    cfg.StrOpt('glusterfs_backup_mount_point',
+               default='$state_path/backup_mount',
+               help='Base dir containing mount point for gluster share.'),
+    cfg.StrOpt('glusterfs_backup_share',
+               default=None,
+               help='GlusterFS share in '
+                    '<hostname|ipv4addr|ipv6addr>:<gluster_vol_name> format. '
+                    'Eg: 1.2.3.4:backup_vol'),
+]
+
+CONF = cfg.CONF
+CONF.register_opts(glusterfsbackup_service_opts)
+
+
+class GlusterfsBackupDriver(posix.PosixBackupDriver):
+    """Provides backup, restore and delete using GlusterFS repository."""
+
+    def __init__(self, context, db_driver=None):
+        self._check_configuration()
+        self.backup_mount_point_base = CONF.glusterfs_backup_mount_point
+        self.backup_share = CONF.glusterfs_backup_share
+        self._execute = putils.execute
+        self._root_helper = utils.get_root_helper()
+        backup_path = self._init_backup_repo_path()
+        super(GlusterfsBackupDriver, self).__init__(context,
+                                                    backup_path=backup_path)
+
+    @staticmethod
+    def _check_configuration():
+        """Raises error if any required configuration flag is missing."""
+        required_flags = ['glusterfs_backup_share']
+        for flag in required_flags:
+            if not getattr(CONF, flag, None):
+                raise exception.ConfigNotFound(path=flag)
+
+    def _init_backup_repo_path(self):
+        remotefsclient = remotefs_brick.RemoteFsClient(
+            'glusterfs',
+            self._root_helper,
+            glusterfs_mount_point_base=self.backup_mount_point_base)
+        remotefsclient.mount(self.backup_share)
+
+        # Ensure we can write to this share
+        mount_path = remotefsclient.get_mount_point(self.backup_share)
+
+        group_id = os.getegid()
+        current_group_id = utils.get_file_gid(mount_path)
+        current_mode = utils.get_file_mode(mount_path)
+
+        if group_id != current_group_id:
+            cmd = ['chgrp', group_id, mount_path]
+            self._execute(*cmd, root_helper=self._root_helper,
+                          run_as_root=True)
+
+        if not (current_mode & stat.S_IWGRP):
+            cmd = ['chmod', 'g+w', mount_path]
+            self._execute(*cmd, root_helper=self._root_helper,
+                          run_as_root=True)
+
+        return mount_path
+
+
+def get_backup_driver(context):
+    return GlusterfsBackupDriver(context)

diff --git a/cinder/tests/unit/backup/drivers/test_backup_glusterfs.py b/cinder/tests/unit/backup/drivers/test_backup_glusterfs.py
new file mode 100644 (file)
index 0000000..a60b06f
--- /dev/null
+++ b/cinder/tests/unit/backup/drivers/test_backup_glusterfs.py
@@ -0,0 +1,99 @@
+# Copyright (c) 2013 Red Hat, Inc.
+# 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.
+"""
+Tests for GlusterFS backup driver.
+
+"""
+import os
+
+import mock
+from os_brick.remotefs import remotefs as remotefs_brick
+from oslo_config import cfg
+
+from cinder.backup.drivers import glusterfs
+from cinder import context
+from cinder import exception
+from cinder import test
+from cinder import utils
+
+CONF = cfg.CONF
+
+FAKE_BACKUP_MOUNT_POINT_BASE = '/fake/mount-point-base'
+FAKE_HOST = 'fake_host'
+FAKE_VOL_NAME = 'backup_vol'
+FAKE_BACKUP_SHARE = '%s:%s' % (FAKE_HOST, FAKE_VOL_NAME)
+FAKE_BACKUP_PATH = os.path.join(FAKE_BACKUP_MOUNT_POINT_BASE,
+                                'e51e43e3c63fd5770e90e58e2eafc709')
+
+
+class BackupGlusterfsShareTestCase(test.TestCase):
+
+    def setUp(self):
+        super(BackupGlusterfsShareTestCase, self).setUp()
+        self.ctxt = context.get_admin_context()
+
+    def test_check_configuration(self):
+        self.override_config('glusterfs_backup_share', FAKE_BACKUP_SHARE)
+        self.mock_object(glusterfs.GlusterfsBackupDriver,
+                         '_init_backup_repo_path',
+                         mock.Mock(return_value=FAKE_BACKUP_PATH))
+
+        with mock.patch.object(glusterfs.GlusterfsBackupDriver,
+                               '_check_configuration'):
+            driver = glusterfs.GlusterfsBackupDriver(self.ctxt)
+        driver._check_configuration()
+
+    def test_check_configuration_no_backup_share(self):
+        self.override_config('glusterfs_backup_share', None)
+        self.mock_object(glusterfs.GlusterfsBackupDriver,
+                         '_init_backup_repo_path',
+                         mock.Mock(return_value=FAKE_BACKUP_PATH))
+
+        with mock.patch.object(glusterfs.GlusterfsBackupDriver,
+                               '_check_configuration'):
+            driver = glusterfs.GlusterfsBackupDriver(self.ctxt)
+        self.assertRaises(exception.ConfigNotFound,
+                          driver._check_configuration)
+
+    def test_init_backup_repo_path(self):
+        self.override_config('glusterfs_backup_share', FAKE_BACKUP_SHARE)
+        self.override_config('glusterfs_backup_mount_point',
+                             FAKE_BACKUP_MOUNT_POINT_BASE)
+        mock_remotefsclient = mock.Mock()
+        mock_remotefsclient.get_mount_point = mock.Mock(
+            return_value=FAKE_BACKUP_PATH)
+        self.mock_object(glusterfs.GlusterfsBackupDriver,
+                         '_check_configuration')
+        self.mock_object(remotefs_brick, 'RemoteFsClient',
+                         mock.Mock(return_value=mock_remotefsclient))
+        self.mock_object(os, 'getegid',
+                         mock.Mock(return_value=333333))
+        self.mock_object(utils, 'get_file_gid',
+                         mock.Mock(return_value=333333))
+        self.mock_object(utils, 'get_file_mode',
+                         mock.Mock(return_value=00000))
+        self.mock_object(utils, 'get_root_helper')
+
+        with mock.patch.object(glusterfs.GlusterfsBackupDriver,
+                               '_init_backup_repo_path'):
+            driver = glusterfs.GlusterfsBackupDriver(self.ctxt)
+        self.mock_object(driver, '_execute')
+        path = driver._init_backup_repo_path()
+
+        self.assertEqual(FAKE_BACKUP_PATH, path)
+        utils.get_root_helper.called_once()
+        mock_remotefsclient.mount.assert_called_once_with(FAKE_BACKUP_SHARE)
+        mock_remotefsclient.get_mount_point.assert_called_once_with(
+            FAKE_BACKUP_SHARE)