Scylla has a long-standing bug (issue #7620) where having many
tombstones in the schema table significantly slows down further
schema operations.
Many cql-pytest tests use new_test_table() to create a temporary test
table with a specific schema. Before this patch, each temporary table
was created with a random name, and deleted after the test. When
running many tests on the same Scylla server, this results in a lot
of tombstones in the schema tables, and really slow schema operations.
For example, look at home much time it takes to run the same test file
N times:
$ test/cql-pytest/run --count N test_filtering.py
N=25 - 16 seconds (total time for the N repetitions)
N=50 - 41 seconds
N=100 - 122 seconds
Notice how progressively slower each repetition is becoming - the
total test time should have been linear in N, but it isn't!
In this patch, we keep a cache of already-deleted table names (not the
tables, just their names!) so as to reuse the same name when we can
instead of inventing a new random name. With this patch, the performance
improvement after some repetitions is amazing (compare to the table above):
N=25 - 14 seconds
N=50 - 29 seconds
N=100 - 46 seconds
Note how the testing time is now more-or-less linear in the number of
repetitions, as expected.
The table-name recycling trick is the same trick I already used in the
past for the translated Cassandra tests (test/cql-pytest/cassandra_tests).
The problem was even more obvious there because those tests create a
lot of different tables. But the same problem also exists in cql-pytest
in general, so let's solve it here too.
Refs #7620
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#10635
Both Scylla and Cassandra support filtering on frozen UDTs, which are
compared using lexicographical order. This patch adds a test to verify
that the behavior here is the same - and indeed it is.
For *non*-frozen UDTs, Cassandra does not allow filtering on them (this
was decided in CASSANDRA-13247), but Scylla does. So we also add a test
on how non-frozen UDTs work - that passes on Scylla (and of course not
in Cassandra).
The two tests here - for frozen and non-frozen UDTs - are identical
(they just call the same function) - to ensure these two cases work the
same. This is important because we can't judge the correctness of the
non-frozen test by comparison to Cassandra - because it can't run there.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Detecting a secondary index by checking for a dot
in the table name is wrong as tables generated by Alternator
may contain a dot in their name.
Instead detect bot hmaterialized view and secondary indexes
using the schema()->is_view() method.
Fixes#10526
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Generally, cql-pytest tests do not, and *should not* rely on looking up
messages in the Scylla log file: Relying on such messages makes it
impossible to run the same test against Cassandra or even a remotely-
installed Scylla, and the tests tend to break when logging (which is not
considered part of our API) changes. Moreover, usually what our dtests
achieve by looking at the log - e.g., figuring out when some event has
happened - can be achieved through official CQL APIs, and this is what
normal users do anyway (users don't normally dig through the log to
figure out when their operation completed).
However, sometimes we do want to write a test to confirm that during a
certain operation, a certain log message gets written to Scylla's log.
A desire to do this was raised by @fruch and @soyacz, so in this patch
I provide a mechanism to do this, and a trivial example - which checks
that a "Creating ..." message appears on the log whenever a table is
created, and "Dropping ..." when the table is deleted.
As is explained in detail in patches in the comment, Scylla's log file
is found automatically, without relying on Scylla's runner (such as
the script test/cql-pytest/run) communicating to the test where the log
file is. If the log file can't be found - e.g., we're testing a remote
Scylla, or if this isn't Scylla, the tests are skipped.
I would like all logfile-testing tests to be in the same file,
test_logs.py. As I explained above, I think it is a mistake for general
tests to check the log file just because they can. I think that the only
tests that should use the log file are tests deliberately written to
check what gets logged - and those can be collected in the same file.
As part of this patch, we add the utility function local_process_id(cql)
to find (if we can) the local process which listens to the connection
"cql". This utility function will later be useful in more places - for
example test_tools.py needs to find Scylla's executable.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20220314151125.2737815-1-nyh@scylladb.com>
Some of the tests in test/cql-pytest share the same table but use
different keys to ensure they don't collide. Before this patch we used a
random key, which was usually fine, but we recently noticed that the
pytest-randomly plugin may cause different tests to run through the *same*
sequence of random numbers and ruin our intent that different tests use
different keys.
So instead of using a *random* key, let's use a *unique* key. We can
achieve this uniqueness trivially - using a counter variable - because
anyway the uniqueness is only needed inside a single temporary table -
which is different in every run.
Another benefit is that it will now be clearer that the tests are
deterministic and not random - the intent of a random_string() key
was never to randomly walk the entire key space (random_string()
anyway had a pretty narrow idea of what a random string looks like) -
it was just to get a unique key.
Refs #9988 (fixes it for cql-pytest, but not for test/alternator)
Signed-off-by: Nadav Har'El <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
Scylla and Cassandra do not allow an empty string as a partition key,
but a materialized view might "convert" a regular string column into a
partition key, and an empty string is a perfectly valid value for this
column. This can result in a view row which has an empty string as a
partition key. This case works in Cassandra, but doesn't in Scylla (the
row with the empty string as a partition key doesn't appear). The
following test demonstrates this difference between Scylla and Cassandra
(it passes on Cassandra, fails on Scylla, and accordingly marked
"xfail").
Refs #9375.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210922115000.290387-1-nyh@scylladb.com>
A first set of wasm-based test cases is added.
The tests include verifying that supported types work
and that validation of the input wasm is performed.
This patch adds tests for two undocumented (as far as I can tell) corner
cases of CQL's string types:
1. The types "text" and "varchar" are not just similar - they are in
fact exactly the same type.
2. All CQL string and blob types ("ascii", "text" or "varchar", "blob")
allow the null character as a valid character inside them. They are
*not* C strings that get terminated by the first null.
These tests pass on both Cassandra and Scylla, so did not expose any
bug, but having such tests is useful to understand these (so-far)
undocumented behaviors - so we can later document them.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210824225641.194146-1-nyh@scylladb.com>
In the alternator and cql-pytest test frameworks, we have some convenient
contextmanager-based functions that allows us to create a temporary
resource (e.g., a table) that will be automatically deleted, for
example:
with create_stream_test_table(...) as table:
test_something(table)
However, our implementation of these functions wasn't safe. We had
code looking like:
table = ...
yield table
table.delete()
The thinking was that the cleanup part (the table.delete()) will be
called after the user's code. However, if the user's code threw
(i.e., a failed assertion), the cleanup wasn't called... When the user's
code throws, it looks as if the "yield" throws. So the correct code
should look like:
table = ...
try:
yield table
finally:
table.delete()
Python's contextmanager documentation indeed gives this idiom in its
example.
This patch fixes all contextmanager implementations in our tests to do
the cleanup even if the user's "with" block throws.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210428083748.552203-1-nyh@scylladb.com>
The min/max aggregators use aggregate_type_for comparators, and the
aggregate_type_for<timeuuid> is regular uuid. But that yields wrong
results; timeuuids should be compared as timestamps.
Fix it by changing aggregate_type_for<timeuuid> from uuid to timeuuid,
so aggregators can distinguish betwen the two. Then specialize the
aggregation utilities for timeuuid.
Add a cql-pytest and change some unit tests, which relied on naive
uuid comparators.
Fixes#7729.
Tests: unit (dev, debug)
Signed-off-by: Dejan Mircevski <dejan@scylladb.com>
Closes#7910
We add a reproducer for issues #7868 and #7875 which are about bugs when
a table has a frozen collection as its clustering key, and it is sorted
in *reverse order*: If we tried to insert an item to such a table using an
unprepared statement, it failed with a wrong error ("invalid set literal"),
but if we try to set up a prepared statement, the result is even worse -
an assertion failure and a crash.
Interestingly, neither of these problems happen without reversed sort order
(WITH CLUSTERING ORDER BY (b DESC)), and we also add a test which
demonstrates that with default (increasing) order, everything works fine.
All tests pass successfully when run against Cassandra.
The fix for both issues was already committed, so I verified these tests
reproduced the bug before that commit, and pass now.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20210110232312.3844408-1-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>
The name of the utility function test_object_name() is confusing - by
starting with the word "test", pytest can think (if it's imported to the
top-level namespace) that it is a test... So this patch gives it a better
name - unique_name().
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20201111140638.809189-1-nyh@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>
