[Test] Add test to check remove brick with open fd

Test case:
1. Create volume, start it and mount it.
2. Open file datafile on mount point and start copying /etc/passwd
   line by line(Make sure that the copy is slow).
3. Start remove-brick of the subvol to which has datafile is hashed.
4. Once remove-brick is complete compare the checksum of /etc/passwd
   and datafile.

Change-Id: I278e819731af03094dcee93963ec1da115297bef
Signed-off-by: kshithijiyer <kshithij.ki@gmail.com>

1 files changed, 107 insertions, 0 deletions

diff --git a/tests/functional/dht/test_remove_brick_with_open_fd.py b/tests/functional/dht/test_remove_brick_with_open_fd.py
new file mode 100644
index 000000000..053114295
--- /dev/null
+++ b/tests/functional/dht/test_remove_brick_with_open_fd.py
@@ -0,0 +1,107 @@
+#  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 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.glusterfile import get_md5sum
+from glustolibs.gluster.volume_libs import get_subvols, shrink_volume
+from glustolibs.gluster.dht_test_utils import find_hashed_subvol
+from glustolibs.io.utils import validate_io_procs, wait_for_io_to_complete
+
+
+@runs_on([['distributed-replicated', 'distributed-dispersed',
+           'distributed-arbiter', 'distributed'], ['glusterfs']])
+class TestRemoveBrickWithOpenFD(GlusterBaseClass):
+
+    def setUp(self):
+
+        self.get_super_method(self, 'setUp')()
+
+        # 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.is_copy_running = False
+
+    def tearDown(self):
+
+        # If I/O processes are running wait from them to complete
+        if self.is_copy_running:
+            if not wait_for_io_to_complete(self.list_of_io_processes,
+                                           self.mounts):
+                raise ExecutionError("Failed to wait for I/O to complete")
+
+        # 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 test_remove_brick_with_open_fd(self):
+        """
+        Test case:
+        1. Create volume, start it and mount it.
+        2. Open file datafile on mount point and start copying /etc/passwd
+           line by line(Make sure that the copy is slow).
+        3. Start remove-brick of the subvol to which has datafile is hashed.
+        4. Once remove-brick is complete compare the checksum of /etc/passwd
+           and datafile.
+        """
+        # Open file datafile on mount point and start copying /etc/passwd
+        # line by line
+        ret, out, _ = g.run(self.mounts[0].client_system,
+                            "cat /etc/passwd | wc -l")
+        self.assertFalse(ret, "Failed to get number of lines of /etc/passwd")
+        cmd = ("cd {}; exec 30<> datafile ;for i in `seq 1 {}`; do "
+               "head -n $i /etc/passwd | tail -n 1 >> datafile; sleep 10; done"
+               .format(self.mounts[0].mountpoint, out.strip()))
+
+        self.list_of_io_processes = [
+            g.run_async(self.mounts[0].client_system, cmd)]
+        self.is_copy_running = True
+
+        # Start remove-brick of the subvol to which has datafile is hashed
+        subvols = get_subvols(self.mnode, self.volname)['volume_subvols']
+        number = find_hashed_subvol(subvols, "/", 'datafile')[1]
+
+        ret = shrink_volume(self.mnode, self.volname, subvol_num=number)
+        self.assertTrue(ret, "Failed to remove-brick from volume")
+        g.log.info("Remove-brick rebalance successful")
+
+        # Validate if I/O was successful or not.
+        ret = validate_io_procs(self.list_of_io_processes, self.mounts)
+        self.assertTrue(ret, "IO failed on some of the clients")
+        self.is_copy_running = False
+
+        # Compare md5checksum of /etc/passwd and datafile
+        md5_of_orginal_file = get_md5sum(self.mounts[0].client_system,
+                                         '/etc/passwd')
+        self.assertIsNotNone(md5_of_orginal_file,
+                             'Unable to get md5 checksum of orignial file')
+        md5_of_copied_file = get_md5sum(
+            self.mounts[0].client_system, '{}/datafile'.format(
+                self.mounts[0].mountpoint))
+        self.assertIsNotNone(md5_of_copied_file,
+                             'Unable to get md5 checksum of copied file')
+        self.assertEqual(md5_of_orginal_file.split(" ")[0],
+                         md5_of_copied_file.split(" ")[0],
+                         "md5 checksum of original and copied file didn't"
+                         " match")
+        g.log.info("md5 checksum of original and copied files are same")