[Test] Add test to add brick, replace brick and fix layout

Test case:
1. Create a volume, start it and mount it.
2. Create files and dirs on the mount point.
3. Add bricks to the volume.
4. Replace 2 old brick to the volume.
5. Trigger rebalance fix layout and wait for it to complete.
6. Check layout on all the bricks through trusted.glusterfs.dht.

Change-Id: Ibc8ded6ce2a54b9e4ec8bf0dc82436fcbcc25f56
Signed-off-by: kshithijiyer <kshithij.ki@gmail.com>

1 files changed, 124 insertions, 0 deletions

diff --git a/tests/functional/dht/test_add_brick_replace_brick_fix_layout.py b/tests/functional/dht/test_add_brick_replace_brick_fix_layout.py
new file mode 100644
index 000000000..66f39ff24
--- /dev/null
+++ b/tests/functional/dht/test_add_brick_replace_brick_fix_layout.py
@@ -0,0 +1,124 @@
+#  Copyright (C) 2020 Red Hat, Inc. <http://www.redhat.com>
+#
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation; either version 2 of the License, or
+#  any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License along`
+#  with this program; if not, write to the Free Software Foundation, Inc.,
+#  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+from random import choice
+
+from glusto.core import Glusto as g
+from glustolibs.gluster.gluster_base_class import GlusterBaseClass, runs_on
+from glustolibs.gluster.exceptions import ExecutionError
+from glustolibs.gluster.brick_ops import add_brick
+from glustolibs.gluster.brick_libs import get_all_bricks
+from glustolibs.gluster.glusterfile import get_fattr
+from glustolibs.gluster.rebalance_ops import (rebalance_start,
+                                              wait_for_fix_layout_to_complete)
+from glustolibs.gluster.volume_libs import (form_bricks_list_to_add_brick,
+                                            replace_brick_from_volume)
+
+
+@runs_on([['distributed-replicated', 'distributed-arbiter'], ['glusterfs']])
+class TestAddBrickReplaceBrickFixLayout(GlusterBaseClass):
+
+    def setUp(self):
+
+        self.get_super_method(self, 'setUp')()
+
+        # Changing dist_count to 3
+        self.volume['voltype']['dist_count'] = 3
+
+        # Creating Volume and mounting the volume
+        ret = self.setup_volume_and_mount_volume([self.mounts[0]])
+        if not ret:
+            raise ExecutionError("Volume creation or mount failed: %s"
+                                 % self.volname)
+
+        self.first_client = self.mounts[0].client_system
+
+    def tearDown(self):
+
+        # Unmounting and cleaning volume
+        ret = self.unmount_volume_and_cleanup_volume([self.mounts[0]])
+        if not ret:
+            raise ExecutionError("Unable to delete volume %s" % self.volname)
+
+        self.get_super_method(self, 'tearDown')()
+
+    def _replace_a_old_added_brick(self, brick_to_be_replaced):
+        """Replace a old brick from the volume"""
+        ret = replace_brick_from_volume(self.mnode, self.volname,
+                                        self.servers, self.all_servers_info,
+                                        src_brick=brick_to_be_replaced)
+        self.assertTrue(ret, "Failed to replace brick %s "
+                        % brick_to_be_replaced)
+        g.log.info("Successfully replaced brick %s", brick_to_be_replaced)
+
+    def _check_trusted_glusterfs_dht_on_all_bricks(self):
+        """Check trusted.glusterfs.dht xattr on the backend bricks"""
+        bricks = get_all_bricks(self.mnode, self.volname)
+        fattr_value = []
+        for brick_path in bricks:
+            node, path = brick_path.split(":")
+            ret = get_fattr(node, "{}".format(path), "trusted.glusterfs.dht")
+            fattr_value += [ret]
+        self.assertEqual(len(set(fattr_value)), 4,
+                         "Value of trusted.glusterfs.dht is not as expected")
+        g.log.info("Successfully checked value of trusted.glusterfs.dht.")
+
+    def test_add_brick_replace_brick_fix_layout(self):
+        """
+        Test case:
+        1. Create a volume, start it and mount it.
+        2. Create files and dirs on the mount point.
+        3. Add bricks to the volume.
+        4. Replace 2 old brick to the volume.
+        5. Trigger rebalance fix layout and wait for it to complete.
+        6. Check layout on all the bricks through trusted.glusterfs.dht.
+        """
+        # Create directories with some files on mount point
+        cmd = ("cd %s; for i in {1..10}; do mkdir dir$i; for j in {1..5};"
+               " do dd if=/dev/urandom of=dir$i/file$j bs=1M count=1; done;"
+               " done" % self.mounts[0].mountpoint)
+        ret, _, _ = g.run(self.first_client, cmd)
+        self.assertFalse(ret, "Failed to create dirs and files.")
+
+        # Orginal brick list before add brick
+        brick_list = get_all_bricks(self.mnode, self.volname)
+        self.assertIsNotNone(brick_list, "Empty present brick list")
+
+        # Add bricks to the volume
+        add_brick_list = form_bricks_list_to_add_brick(
+            self.mnode, self.volname, self.servers, self.all_servers_info)
+        self.assertIsNotNone(add_brick_list, "Empty add brick list")
+
+        ret, _, _ = add_brick(self.mnode, self.volname, add_brick_list)
+        self.assertFalse(ret, "Failed to add bricks to the volume")
+        g.log.info("Successfully added bricks to the volume")
+
+        # Replace 2 old bricks to the volume
+        for _ in range(0, 2):
+            brick = choice(brick_list)
+            self._replace_a_old_added_brick(brick)
+            brick_list.remove(brick)
+
+        # Start rebalance and wait for it to complete
+        ret, _, _ = rebalance_start(self.mnode, self.volname, fix_layout=True)
+        self.assertFalse(ret, "Failed to start rebalance on volume")
+
+        ret = wait_for_fix_layout_to_complete(self.mnode, self.volname,
+                                              timeout=800)
+        self.assertTrue(ret, "Rebalance failed on volume")
+
+        # Check layout on all the bricks through trusted.glusterfs.dht
+        self._check_trusted_glusterfs_dht_on_all_bricks()