pre/post cmd tests

This commit is contained in:
Edwin Eefting 2021-06-22 12:43:52 +02:00
parent 119225ba5b
commit c5363a1538
3 changed files with 91 additions and 42 deletions

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@ -419,7 +419,9 @@ decompression -> custom recv pipes -> buffer -> zfs recv
## Running custom commands before and after snapshotting
If you need, e.g. to quiesce a couple of mysql databases to make on-disk data consistent before snapshotting, you can use the `--pre-snapshot-cmd` and `--post-snapshot-cmd` options.
You can run commands before and after the snapshot to freeze databases to make the on for example to make the on-disk data consistent before snapshotting.
The commands will be executed on the source side. Use the `--pre-snapshot-cmd` and `--post-snapshot-cmd` options for this.
For example:
@ -432,9 +434,10 @@ zfs-autobackup \
backupfs1
```
The post-snapshot commands are ALWAYS executed, even if a pre-snapshot command or the actual snapshot fail.
Failure handling during pre/post commands:
A failure of a post-snapshot command is non-fatal and will be ignored. The remaining post-snapshot commands wont be executed in that case.
* If a pre-command fails, zfs-autobackup will exit with an error. (after executing the post-commands)
* All post-commands are always executed. Even if the pre-commands or actual snapshot have failed. This way you can be sure that stuff is always cleanedup and unfreezed.
## Tips

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@ -1,6 +1,6 @@
from basetest import *
from zfs_autobackup.LogStub import LogStub
from zfs_autobackup.ExecuteNode import ExecuteError
class TestZfsNode(unittest2.TestCase):
@ -9,16 +9,15 @@ class TestZfsNode(unittest2.TestCase):
prepare_zpools()
# return super().setUp()
def test_consistent_snapshot(self):
logger=LogStub()
description="[Source]"
node=ZfsNode("test", logger, description=description)
logger = LogStub()
description = "[Source]"
node = ZfsNode("test", logger, description=description)
with self.subTest("first snapshot"):
node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1",100000)
r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
self.assertEqual(r,"""
node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1", 100000)
r = shelltest("zfs list -H -o name -r -t all " + TEST_POOLS)
self.assertEqual(r, """
test_source1
test_source1/fs1
test_source1/fs1@test-1
@ -33,11 +32,10 @@ test_source2/fs3/sub
test_target1
""")
with self.subTest("second snapshot, no changes, no snapshot"):
node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-2",1)
r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
self.assertEqual(r,"""
node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-2", 1)
r = shelltest("zfs list -H -o name -r -t all " + TEST_POOLS)
self.assertEqual(r, """
test_source1
test_source1/fs1
test_source1/fs1@test-1
@ -53,9 +51,9 @@ test_target1
""")
with self.subTest("second snapshot, no changes, empty snapshot"):
node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-2",0)
r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
self.assertEqual(r,"""
node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-2", 0)
r = shelltest("zfs list -H -o name -r -t all " + TEST_POOLS)
self.assertEqual(r, """
test_source1
test_source1/fs1
test_source1/fs1@test-1
@ -73,31 +71,82 @@ test_source2/fs3/sub
test_target1
""")
def test_consistent_snapshot_prepostcmds(self):
logger = LogStub()
description = "[Source]"
node = ZfsNode("test", logger, description=description, debug_output=True)
with self.subTest("Test if all cmds are executed correctly (no failures)"):
with OutputIO() as buf:
with redirect_stdout(buf):
node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1",
0,
pre_snapshot_cmds=["echo pre1", "echo pre2"],
post_snapshot_cmds=["echo post1 >&2", "echo post2 >&2"]
)
self.assertIn("STDOUT > pre1", buf.getvalue())
self.assertIn("STDOUT > pre2", buf.getvalue())
self.assertIn("STDOUT > post1", buf.getvalue())
self.assertIn("STDOUT > post2", buf.getvalue())
with self.subTest("Failure in the middle, only pre1 and both post1 and post2 should be executed, no snapshot should be attempted"):
with OutputIO() as buf:
with redirect_stdout(buf):
with self.assertRaises(ExecuteError):
node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1",
0,
pre_snapshot_cmds=["echo pre1", "false", "echo pre2"],
post_snapshot_cmds=["echo post1", "false", "echo post2"]
)
print(buf.getvalue())
self.assertIn("STDOUT > pre1", buf.getvalue())
self.assertNotIn("STDOUT > pre2", buf.getvalue())
self.assertIn("STDOUT > post1", buf.getvalue())
self.assertIn("STDOUT > post2", buf.getvalue())
with self.subTest("Snapshot fails"):
with OutputIO() as buf:
with redirect_stdout(buf):
with self.assertRaises(ExecuteError):
#same snapshot name as before so it fails
node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1",
0,
pre_snapshot_cmds=["echo pre1", "echo pre2"],
post_snapshot_cmds=["echo post1", "echo post2"]
)
print(buf.getvalue())
self.assertIn("STDOUT > pre1", buf.getvalue())
self.assertIn("STDOUT > pre2", buf.getvalue())
self.assertIn("STDOUT > post1", buf.getvalue())
self.assertIn("STDOUT > post2", buf.getvalue())
def test_getselected(self):
logger=LogStub()
description="[Source]"
node=ZfsNode("test", logger, description=description)
s=pformat(node.selected_datasets(exclude_paths=[], exclude_received=False))
logger = LogStub()
description = "[Source]"
node = ZfsNode("test", logger, description=description)
s = pformat(node.selected_datasets(exclude_paths=[], exclude_received=False))
print(s)
#basics
self.assertEqual (s, """[(local): test_source1/fs1,
# basics
self.assertEqual(s, """[(local): test_source1/fs1,
(local): test_source1/fs1/sub,
(local): test_source2/fs2/sub]""")
#caching, so expect same result after changing it
# caching, so expect same result after changing it
subprocess.check_call("zfs set autobackup:test=true test_source2/fs3", shell=True)
self.assertEqual (s, """[(local): test_source1/fs1,
self.assertEqual(s, """[(local): test_source1/fs1,
(local): test_source1/fs1/sub,
(local): test_source2/fs2/sub]""")
def test_validcommand(self):
logger=LogStub()
description="[Source]"
node=ZfsNode("test", logger, description=description)
logger = LogStub()
description = "[Source]"
node = ZfsNode("test", logger, description=description)
with self.subTest("test invalid option"):
self.assertFalse(node.valid_command(["zfs", "send", "--invalid-option", "nonexisting"]))
@ -105,21 +154,19 @@ test_target1
self.assertTrue(node.valid_command(["zfs", "send", "-v", "nonexisting"]))
def test_supportedsendoptions(self):
logger=LogStub()
description="[Source]"
node=ZfsNode("test", logger, description=description)
logger = LogStub()
description = "[Source]"
node = ZfsNode("test", logger, description=description)
# -D propably always supported
self.assertGreater(len(node.supported_send_options),0)
self.assertGreater(len(node.supported_send_options), 0)
def test_supportedrecvoptions(self):
logger=LogStub()
description="[Source]"
#NOTE: this could hang via ssh if we dont close filehandles properly. (which was a previous bug)
node=ZfsNode("test", logger, description=description, ssh_to='localhost')
logger = LogStub()
description = "[Source]"
# NOTE: this could hang via ssh if we dont close filehandles properly. (which was a previous bug)
node = ZfsNode("test", logger, description=description, ssh_to='localhost')
self.assertIsInstance(node.supported_recv_options, list)
if __name__ == '__main__':
unittest.main()

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@ -213,7 +213,6 @@ class ZfsNode(ExecuteNode):
self.run(cmd=shlex.split(cmd), readonly=False)
except Exception as e:
pass
self.warning("Post snapshot command failed, ignoring.")