cae8a7222e
Before this patch, the regular_column_transformation constructor, which we used in Alternator GSIs to generates a view key from a regular-column cell, accepted a cell of any size. As a reviewer (Avi) noticed, very long cells are possible, well beyond what Scylla allows for keys (64KB), and because regular_column_transformation stores such values in a contiguous "bytes" object it can cause stalls. But allowing oversized attributes creates an even more accute problem: While view building (backfilling in DynamoDB jargon), if we encounter an oversized (>64KB) key, the view building step will fail and the entire view building will hang forever. This patch fixes both problems by adding to regular_column_transformation's constructor the check that if the cell is 64KB or larger, an empty value is returned for the key. This causes the backfilling to silently skip this item, which is what we expect to happen (backfilling cannot do anything to fix or reject the pre-existing items in the best table). A test test_gsi_updatetable.py::test_gsi_backfill_oversized_key is introduced to reproduce this problem and its fix. The test adds a 65KB attribute to a base table, and then adds GSIs to this table with this attribute as its partition key or its sort key. Before this patch, the backfilling process for the new GSIs hangs, and never completes. After this patch, the backfilling completes and as expected contains other base-table items but not the item with the oversized attribute. The new test also passes on DynamoDB. However, while implementing this fix I realized that issue #10347 also exists for GSIs. Issue #10347 is about the fact that DynamoDB limits partition key and sort key attributes to 2048 and 1024 bytes, respectively. In the fix described above we only handled the accute case of lengths above 64 KB, but we should actually skip items whose GSI keys are over 2048 or 1024 bytes - not 64KB. This extra checking is not handled in this patch, and is part of a wider existing issue: Refs #10347 Signed-off-by: Nadav Har'El <nyh@scylladb.com>
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.