af4afc84ec
The auxiliary function `eventually()` (defined in `test/lib/eventually.hh`)
tries to execute a passed function. If it throws, `eventually()` sleeps
for `2^#previous_attempts` milliseconds and tries to perform it again.
The default limit of attempts is 17.
In `test_view_update_generating_writetime`, right before the last test
case, we perform:
```cql
UPDATE t USING TTL 10 AND TIMESTAMP 8 SET g=40 WHERE k=1 AND c=1;
```
The test case itself executes:
```cql
SELECT WRITETIME(g) FROM t;
```
and asserts that the result of the query is equal to 8, i.e. it
corresponds to the timestamp of the last write to the table `t`.
However, if the test case keeps failing, then during its 14th attempt
(so affter sleeping for at least `2^14 - 1` milliseconds, which amounts
to about 16 seconds), we'll observe the following error:
```
[Exception] - std::runtime_error: Expected row not found: [0000000000000008] not in {result_message::rows {row: null}}
```
The reason behind it is the specified TTL is too short. 10 seconds will
have already passed before the 14th attempt, so the value in the column
`g` will be `NULL` again. In particular, the `WRITETIME(g)` will no
longer be equal to `8`.
To solve that issue, we change the TTL in the CQL statement to 300.
The time spent on 17 loops of `eventually()` amounts to about
`2^18 - 1` milliseconds, which is about 263 seconds. That's why
setting the TTL to 300 seconds should be enough to prevent the error
from occurring.
Scylla in-source tests.
For details on how to run the tests, see docs/dev/testing.md
Shared C++ utils, libraries are in lib/, for Python - pylib/
alternator - Python tests which connect to a single server and use the DynamoDB API unit, boost, raft - unit tests in C++ cqlpy - Python tests which connect to a single server and use CQL topology* - tests that set up clusters and add/remove nodes cql - approval tests that use CQL and pre-recorded output rest_api - tests for Scylla REST API Port 9000 scylla-gdb - tests for scylla-gdb.py helper script nodetool - tests for C++ implementation of nodetool
If you can use an existing folder, consider adding your test to it. New folders should be used for new large categories/subsystems, or when the test environment is significantly different from some existing suite, e.g. you plan to start scylladb with different configuration, and you intend to add many tests and would like them to reuse an existing Scylla cluster (clusters can be reused for tests within the same folder).
To add a new folder, create a new directory, and then
copy & edit its suite.ini.