The test cases check if it's possible to set and/or alter
storage options for keyspaces with CQL, and whether the changes
are reflected in the schema tables.
Issue #8968 no longer exists when Raft-based schema updates are enabled
in Scylla (with --experimental-features=raft). Before we can close this
issue we need a way to re-run its test
test_keyspace.py::test_concurrent_create_and_drop_keyspace
with Raft and see it pass. But we also want the tests to continue to run
by default the older raft-less schema updates - so that this mode doesn't
regress during the potentially-long duration that it's still the default!
The solution in this patch is:
1. Introduce a "--raft" option to test/cql-pytest/run, which runs the tests
against a Scylla with the raft experimental feature, while the default is
still to run without it.
2. Introduce a text fixture "fails_without_raft" which marks a test which
is expected to fail with the old pre-raft code, but is expected to
pass in the new code.
3. Mark the test test_concurrent_create_and_drop_keyspace with this new
"fails_without_raft".
After this patch, running
test/cql-pytest/run --raft
test_keyspace.py::test_concurrent_create_and_drop_keyspace
Passes, which shows that issue 8968 was fixed (in Raft mode) - so we can say:
Fixes#8968
Running the same test without "--raft" still xfails (an expected failure).
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20220208162732.260888-1-nyh@scylladb.com>
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
After commit 76227fa ("cql-pytest: use NetworkTopologyStrategy, not
SimpleStrategy"), the cql-pytest tests now NetworkTopologyStrategy instead
of SimpleStrategy in the test keyspaces. The tests continued to use the
"replication_factor" option. The support for this option is a relatively
recent, and was only added to Cassandra in the 4.0 release series
(see https://issues.apache.org/jira/browse/CASSANDRA-14303). So users
who happen to have Cassandra 3 installed and want to run a cql-pytest
against it will see the test failing when it can't create a keyspace.
This patch trivially fixes the problem by using the name of the current
DC (automatically determined) instead of the word 'replication_factor'.
Almost all tests are fixed by a single fix to the test_keyspace fixture
which creates one keyspace used by most tests. Additional changes were
needed in test_keyspace.py, for tests which explicitly create keyspaces.
I tested the result on Cassandra 3.11.10, Cassandra 4 (git master) and
Scylla.
Fixes#8990
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210708123428.811184-1-nyh@scylladb.com>
We know that today in Scylla concurrent schema changes done on different
coordinators are not safe - and we plan to address this problem with Raft.
However, the test in this patch - reproducing issue #8968 - demonstrates
that even on a single node concurrent schema changes are not safe:
The test involves one thread which constantly creates a keyspace and
then a table in it - and a second thread which constantly deletes this
keyspace. After doing this for a while, the schema reaches an inconsistent
state: The keyspace is at a state of limbo where it cannot be dropped
(dropping it succeeds, but doesn't actually drop it), and a new keyspace
cannot be created under the same name).
Note that to reproduce this bug, it was important that the test create
both a keyspace and a table. Were the test to just create an empty keyspace,
without a table in it, the bug would not be reproduced.
Refs #8968.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210704121049.662169-1-nyh@scylladb.com>
All tests in cql-pytest use a test keyspace created with the SimpleStrategy
replication strategy. This was never intentional. We are recommending to
users that they should use NetworkTopologyStrategy instead, and even
want to deprecate SimpleStrategy (this is #8586), so tests should stop
using SimpleStrategy and should start using the same strategy users would
use in their applications - NetworkTopologyStrategy.
Almost all tests are fixed by a single change in conftest.py which
changes how "test_keyspace" is created. But additionally, tests in
test_keyspace.py which explicitly create keyspaces (that's the point of
that test file...) also had to be modified to use NetworkTopologyStrategy.
Note that none of the tests relied on any special features or
implementation details of SimpleStrategy.
This patch is part of the bigger effort to remove reliance on
SimpleStrategy from all tests, of all types - which we will need to do if
we ever want to forbid SimpleStrategy by default. The issue of that effort:
Refs #8638
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210620102341.195533-1-nyh@scylladb.com>
This adds some test cases for ALTER KEYSPACE:
- ALTER KEYSPACE happy path
- ALTER KEYSPACE wit invalid options
- ALTER KEYSPACE for non-existing keyspace
- CREATE and ALTER KEYSPACE using NetworkTopologyStrategy with
non-existing data center in configuration, which triggers a bug in
Scylla:
https://github.com/scylladb/scylla/issues/7595
Message-Id: <20201112073110.39475-1-penberg@scylladb.com>
This patch introduces a new way to do functional testing on Scylla,
similar to Alternator's test/alternator but for the CQL API:
The new tests, in test/cql-pytest, are written in Python (using the pytest
framework), and use the standard Python CQL driver to connect to any CQL
implementation - be it Scylla, Cassandra, Amazon Keyspaces, or whatever.
The use of standard CQL allows the test developer to easily run the same
test against both Scylla and Cassandra, to confirm that the behaviour that
our test expects from Scylla is really the "correct" (meaning Cassandra-
compatible) behavior.
A developer can run Scylla or Cassandra manually, and run "pytest"
to connect to them (see README.md for more instructions). But even more
usefully, this patch also provides two scripts: test/cql-pytest/run and
test/cql-pytest/run-cassandra. These scripts automate the task of running
Scylla or Cassandra (respectively) in a random IP address and temporary
directory, and running the tests against it.
The script test/cql-pytest/run is inspired by the existing test run
scripts of Alternator and Redis, but rewritten in Python in a way that
will make it easy to rewrite - in a future patch - all these other run
scripts to use the same common code to safely run a test server in a
temporary directory.
"run" is extremely quick, taking around two seconds to boot Scylla.
"run-cassandra" is slower, taking 13 seconds to boot Cassandra (maybe
this can be improved in the future, I still don't know how).
The tests themselves take milliseconds.
Although the 'run' script runs a single Scylla node, the developer
can also bring up any size of Scylla or Cassandra cluster manually
and run the tests (with "pytest") against this cluster.
This new test framework differs from the existing alternatives in the
following ways:
dtest: dtest focuses on testing correctness of *distributed* behavior,
involving clusters of multiple nodes and often cluster changes
during the test. In contrast, cql-pytest focuses on testing the
*functionality* of a large number of small CQL features - which
can usually be tested on a single-node cluster.
Additionally, dtest is out-of-tree, while cql-pytest is in-tree,
making it much easier to add or change tests together with code
patches.
Finally, dtest tests are notoriously slow. Hundreds of tests in
the new framework can finish faster than a single dtest.
Slow and out-of-tree tests are difficult to write, and I believe
this explains why no developer loves writing dtests and maintainers
do not insist on having them. I hope cql-pytest can change that.
test/cql: The defining difference between the existing test/cql suite
and the new test/cql-pytest is the new framework is programmatic,
Python code, not a text file with desired output. Tests written with
` code allow things like looping, repeating the same test with different
parameters. Also, when a test fails, it makes it easier to understand
why it failed beyond just the fact that the output changed.
Moreover, in some cases, the output changes benignly and cql-pytest
may check just the desired features of the output.
Beyond this, the current version of test/cql cannot run against
Cassandra. test/cql-pytest can.
The primary motivation for this new framework was
https://github.com/scylladb/scylla/issues/7443 - where we had an
esoteric feature (sort order of *partitions* when an index is addded),
which can be shown in Cqlsh to have what we think is incorrect behavior,
and yet: 1. We didn't catch this bug because we never wrote a test for it,
possibly because it too difficult to contribute tests, and 2. We *thought*
that we knew what Cassandra does in this case, but nobody actually tested
it. Yes, we can test it manually with cqlsh, but wouldn't everything be
better if we could just run the same test that we wrote for Scylla against
Cassandra?
So one of the tests we add in this patch confirms issue #7443 in Scylla,
and that our hunch was correct and Cassandra indeed does not have this
problem. I also add a few trivial tests for keyspace create and drop,
as additional simple examples.
Refs #7443.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20201110110301.672148-1-nyh@scylladb.com>
