[PATCH v2 8/8] iotests: add 306 to test reconnect on nbd open

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 tests/qemu-iotests/306        | 71 +++++++++++++++++++++++++++++++++++
 tests/qemu-iotests/306.out    | 11 ++++++
 tests/qemu-iotests/group      |  1 +
 tests/qemu-iotests/iotests.py | 11 ++++++
 4 files changed, 94 insertions(+)
 create mode 100755 tests/qemu-iotests/306
 create mode 100644 tests/qemu-iotests/306.out

diff --git a/tests/qemu-iotests/306 b/tests/qemu-iotests/306
new file mode 100755
index 0000000000..85216cf088
--- /dev/null
+++ b/tests/qemu-iotests/306
@@ -0,0 +1,71 @@
+#!/usr/bin/env python3
+#
+# Test nbd reconnect on open
+#
+# Copyright (c) 2020 Virtuozzo International GmbH
+#
+# 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
+# (at your option) 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, see <http://www.gnu.org/licenses/>.
+#
+
+import time
+
+import iotests
+from iotests import qemu_img_create, file_path, qemu_io_popen, qemu_nbd, \
+    qemu_io_log, log
+
+iotests.script_initialize(supported_fmts=['qcow2'])
+
+disk, nbd_sock = file_path('disk', 'nbd-sock')
+
+
+def create_args(open_timeout):
+    return ['--image-opts', '-c', 'read 0 1M',
+            f'driver=nbd,open-timeout={open_timeout},'
+            f'server.type=unix,server.path={nbd_sock}']
+
+
+def check_fail_to_connect(open_timeout):
+    log(f'Check fail to connect with {open_timeout} seconds of timeout')
+
+    start_t = time.time()
+    qemu_io_log(*create_args(open_timeout))
+    delta_t = time.time() - start_t
+
+    max_delta = open_timeout + 0.2
+    if delta_t >= open_timeout and delta_t < max_delta:
+        log(f'qemu_io finished in {open_timeout}..{max_delta} seconds, OK')
+    else:
+        note = 'too early' if delta_t < open_timeout else 'too long'
+        log(f'qemu_io finished in {delta_t:.1f} seconds, {note}')
+
+
+qemu_img_create('-f', iotests.imgfmt, disk, '1M')
+
+# Start NBD client when NBD server is not yet running. It should not fail, but
+# wait for 5 seconds for the server to be available.
+client = qemu_io_popen(*create_args(5))
+
+time.sleep(1)
+qemu_nbd('-k', nbd_sock, '-f', iotests.imgfmt, disk)
+
+# client should succeed
+log(client.communicate()[0], filters=[iotests.filter_qemu_io])
+
+# Server was started without --persistent flag, so it should be off now. Let's
+# check it and it the same time check that with open-timeout=0 client fails
+# immediately.
+check_fail_to_connect(0)
+
+# Check that we will fail after non-zero timeout if server is still unavailable
+check_fail_to_connect(1)
diff --git a/tests/qemu-iotests/306.out b/tests/qemu-iotests/306.out
new file mode 100644
index 0000000000..a35ae30ea4
--- /dev/null
+++ b/tests/qemu-iotests/306.out
@@ -0,0 +1,11 @@
+read 1048576/1048576 bytes at offset 0
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+Check fail to connect with 0 seconds of timeout
+qemu-io: can't open: Failed to connect to 'TEST_DIR/PID-nbd-sock': No such file or directory
+
+qemu_io finished in 0..0.2 seconds, OK
+Check fail to connect with 1 seconds of timeout
+qemu-io: can't open: Failed to connect to 'TEST_DIR/PID-nbd-sock': No such file or directory
+
+qemu_io finished in 1..1.2 seconds, OK
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index 2960dff728..6ea7b83c1e 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -314,5 +314,6 @@
 303 rw quick
 304 rw quick
 305 rw quick
+306 rw auto quick
 307 rw quick export
 309 rw auto quick
diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index d7b488f7ee..2530185220 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -208,6 +208,17 @@ def qemu_io_log(*args):
     log(result, filters=[filter_testfiles, filter_qemu_io])
     return result
 
+def qemu_io_popen(*args):
+    '''Run qemu-nbd in daemon mode and return the parent's exit code'''
+    default_args = qemu_io_args[:]
+
+    if ('-f' in args or '--image-opts' in args) and '-f' in default_args:
+        ind = default_args.index('-f')
+        del default_args[ind:ind+2]
+
+    return subprocess.Popen(default_args + list(args), stdout=subprocess.PIPE,
+                            stderr=subprocess.STDOUT, universal_newlines=True)
+
 def qemu_io_silent(*args):
     '''Run qemu-io and return the exit code, suppressing stdout'''
     args = qemu_io_wrap_args(args)
-- 
2.21.3