BTI indexes only store encoded prefixes of partition keys,
not the whole keys. They can't reliably implement `get_partition_key`.
The index reader interface must be weakened and callers must
be adapted.
The test test_tombstone_gc_disabled_on_pending_replica was added when
we fixed (#20788) the potential problem with data resurrection during
file based streaming. The issue was occurring only in Enterprise, but
we added the fix in OSS to limit code divergence. This test was added
together with the fix in OSS with the idea to guard this change in OSS.
The real reproducer and test for this fix was added later, after the
fix was ported into Enterprise.
It is in: test/cluster/test_resurrection.py
Since Enterprise has been merged into OSS, there is no more need to
keep the test test_tombstone_gc_disabled_on_pending_replica. Also,
it is flaky with very low probability of failure, making it difficult
to investigate the cause of failure.
Fixes: #22182Closesscylladb/scylladb#25134
This PR introduces a new Key Provider to support Azure Key Vault as a Key Management System (KMS) for Encryption at Rest. The core design principle is the same as in the AWS and GCP key providers - an externally provided Vault key that is used to protect local data encryption keys (a process known as "key wrapping").
In more detail, this patch series consists of:
* Multiple Azure credential sources, offering a variety of authentication options (Service Principals, Managed Identities, environment variables, Azure CLI).
* The Azure host - the Key Vault endpoint bridge.
* The Azure Key Provider - the interface for the Azure host.
* Unit tests using real Azure resources (credentials and Vault keys).
* Log filtering logic to not expose sensitive data in the logs (plaintext keys, credentials, access tokens).
This is part of the overall effort to support Azure deployments.
Testing done:
* Unit tests.
* Manual test on an Azure VM with a Managed Identity.
* Manual test with credentials from Azure CLI.
* Manual test of `--azure-hosts` cmdline option.
* Manual test of log filtering.
Remaining items:
- [x] Create necessary Azure resources for CI.
- [x] Merge pipeline changes (https://github.com/scylladb/scylla-pkg/pull/5201).
Closes https://github.com/scylladb/scylla-enterprise/issues/1077.
New feature. No backport is needed.
Closesscylladb/scylladb#23920
* github.com:scylladb/scylladb:
docs: Document the Azure Key Provider
test: Add tests for Azure Key Provider
pylib: Add mock server for Azure Key Vault
encryption: Define and enable Azure Key Provider
encryption: azure: Delegate hosts to shard 0
encryption: Add Azure host cache
encryption: Add config options for Azure hosts
encryption: azure: Add override options
encryption: azure: Add retries for transient errors
encryption: azure: Implement init()
encryption: azure: Implement get_key_by_id()
encryption: azure: Add id-based key cache
encryption: azure: Implement get_or_create_key()
encryption: azure: Add credentials in Azure host
encryption: azure: Add attribute-based key cache
encryption: azure: Add skeleton for Azure host
encryption: Templatize get_{kmip,kms,gcp}_host()
encryption: gcp: Fix typo in docstring
utils: azure: Get access token with default credentials
utils: azure: Get access token from Azure CLI
utils: azure: Get access token from IMDS
utils: azure: Get access token with SP certificate
utils: azure: Get access token with SP secret
utils: rest: Add interface for request/response redaction logic
utils: azure: Declare all Azure credential types
utils: azure: Define interface for Azure credentials
utils: Introduce base64url_{encode,decode}
As requested in #22102, #22103 and #22105 moved the files and fixed other includes and build system.
Moved files:
- clustering_bounds_comparator.hh
- keys.cc
- keys.hh
- clustering_interval_set.hh
- clustering_key_filter.hh
- clustering_ranges_walker.hh
- compound_compat.hh
- compound.hh
- full_position.hh
Fixes: #22102Fixes: #22103Fixes: #22105Closesscylladb/scylladb#25082
Refs #24551
Drops background flush for proxy output stream (because test), and
also ensures we do explicit flush + close on exception in write loop.
Ensures we don't hide actual exceptions with asserts.
Closesscylladb/scylladb#25146
This test checks that the paxos state is preserved in case
of tablet rebuild. This happens e.g. when a node is lost
permanently and another node is started to replace it.
LWT is now supported for tablets, but this requires LWT_WITH_TABLETS
feature. We migrate the test so that it checks the error messages in
case the feature is not supported.
This test verifies that Paxos state is correctly migrated when
the base table's tablet is migrated. This test fails if Paxos
state is stored in system.paxos, as the final Paxos read would
reflect conflicting outcomes from both prior LWT operations.
We call paxos_store::ensure_initialized in the beginning of
storage_proxy::cas to create a paxos state table for a user table if
it doesn't exist. When the LWT coordinator sends RPCs to replicas,
some of them may not yet have the paxos schema. In
paxos_store::get_paxos_state_schema we just wait for them to appear,
or throw 'no_such_column_family' if the base table was dropped.
Introduce paxos_store abstraction to isolate Paxos state access.
Prepares for supporting either system.paxos or a co-located
table as the storage backend.
Skip removing any artifacts when -s provided between test.py invocation.
Logs from the previous run will be overridden if tests were executed one
more time. Fox example:
1. Execute tests A, B, C with parameter -s
2. All logs are present even if tests are passed
3. Execute test B with parameter -s
4. Logs for A and C are from the first run
5. Logs for B are from the most recent run
Backport is not needed, since it framework enhancement.
Closesscylladb/scylladb#24838
* github.com:scylladb/scylladb:
test.py: skip cleaning artifacts when -s provided
test.py: move deleting directory to prepare_dir
When a node shuts down, in storage service, after storage_proxy RPCs are stopped, some write handlers within storage_proxy may still be waiting for background writes to complete. These handlers hold appropriate ERMs to block schema changes before the write finishes. After the RPCs are stopped, these writes cannot receive the replies anymore.
If, at the same time, there are RPC commands executing `barrier_and_drain`, they may get stuck waiting for these ERM holders to finish, potentially blocking node shutdown until the writes time out.
This change introduces cancellation of all outstanding write handlers from storage_service after the storage proxy RPCs were stopped.
Fixesscylladb/scylladb#23665
Backport: since this fixes an issue that frequently causes issues in CI, backport to 2025.1, 2025.2, and 2025.3.
Closesscylladb/scylladb#24714
* https://github.com/scylladb/scylladb:
storage_service: Cancel all write requests on storage_proxy shutdown
test: Add test for unfinished writes during shutdown and topology change
In the previous commit, we made it possible to set `recovery_leader`
on each node just before restarting it. Here, we change all the
tests of the Raft-based recovery procedure to use and test this option.
In the new Raft-based recovery procedure, live nodes join the new
group 0 one by one during a rolling restart. There is a time window when
some of them are in the old group 0, while others are in the new group
0. This causes a group 0 mismatch in `gossiper::handle_syn_msg`. The
current solution for this problem is to ignore group 0 mismatches if
`recovery_leader` is set on the local node and to ask the administrator
to perform the rolling restart in the following way:
- set `recovery_leader` in `scylla.yaml` on all live nodes,
- send the `SIGHUP` signal to all Scylla processes to reload the config,
- proceed with the rolling restart.
This commit makes `gossiper::handle_syn_msg` ignore group 0 mismatches
when exactly one of the two gossiping nodes has `recovery_leader` set.
We achieve this by adding `recovery_leader` to `gossip_digest_syn`.
This change makes setting `recovery_leader` earlier on all nodes and
reloading the config unnecessary. From now on, the administrator can
simply restart each node with `recovery_leader` set.
However, note that nodes that join group 0 must have `recovery_leader`
set until all nodes join the new group 0. For example, assume that we
are in the middle of the rolling restart and one of the nodes in the new
group 0 crashes. It must be restarted with `recovery_leader` set, or
else it would reject `gossip_digest_syn` messages from nodes in the old
group 0. To avoid problems in such cases, we will continue to recommend
setting `recovery_leader` in `scylla.yaml` instead of passing it as
a command line argument.
During a graceful node shutdown, RPC listeners are stopped in `storage_service::drain_on_shutdown`
as one of the first steps. However, even after RPCs are shut down, some write handlers in
`storage_proxy` may still be waiting for background writes to complete. These handlers retain the ERM.
Since the RPC subsystem is no longer active, replies cannot be received, and if any RPC commands are
concurrently executing `barrier_and_drain`, they may get stuck waiting for those writes. This can block
the messaging server shutdown and delay the entire shutdown process until the write timeout occurs.
This change introduces the cancellation of all outstanding write handlers in `storage_proxy`
during shutdown to prevent unnecessary delays.
Fixesscylladb/scylladb#23665
This test reproduces an issue where a topology change and an ongoing write query
during query coordinator shutdown can cause the node to get stuck.
When a node receives a write request, it creates a write handler that holds
a copy of the current table's ERM (Effective Replication Map). The ERM ensures
that no topology or schema changes occur while the request is being processed.
After the query coordinator receives the required number of replica write ACKs
to satisfy the consistency level (CL), it sends a reply to the client. However,
the write response handler remains alive until all replicas respond — the remaining
writes are handled in the background.
During shutdown, when all network connections are closed, these responses can no longer
be received. As a result, the write response handler is only destroyed once the write
timeout is reached.
This becomes problematic because the ERM held by the handler blocks topology or schema
change commands from executing. Since shutdown waits for these commands to complete,
this can lead to unnecessary delays in node shutdown and restarts, and occasional
test case failures.
Test for: scylladb/scylladb#23665
As they are wasteful in many cases, it is better
to move the tablet_map if possible, or clone
it gently in an async fiber.
Add clone() and clone_gently() methods to
allow explicit copies.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
It is currently used only by tests that could very well
do with mutate_tablet_map_async.
This will simplify the following patch to prevent
accidental copy of the tablet_map, provding explicit
clone/clone_gently methods.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
If a test fails very early (still have to find why), test.py
crashes while flushing a non-existent log_file, as shown below.
To fix, initialize the property to None and check it during
cleanup.
```
================================================================================
[N/TOTAL] SUITE MODE RESULT TEST
------------------------------------------------------------------------------
'ScyllaServer' object has no attribute 'log_file'
test_cluster_features Traceback (most recent call last):
File "/home/avi/scylla-maint/./test.py", line 816, in <module>
sys.exit(asyncio.run(main()))
~~~~~~~~~~~^^^^^^^^
File "/usr/lib64/python3.13/asyncio/runners.py", line 195, in run
return runner.run(main)
~~~~~~~~~~^^^^^^
File "/usr/lib64/python3.13/asyncio/runners.py", line 118, in run
return self._loop.run_until_complete(task)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^
File "/usr/lib64/python3.13/asyncio/base_events.py", line 725, in run_until_complete
return future.result()
~~~~~~~~~~~~~^^
File "/home/avi/scylla-maint/./test.py", line 523, in main
total_tests_pytest, failed_pytest_tests = await run_all_tests(signaled, options)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/avi/scylla-maint/./test.py", line 452, in run_all_tests
failed += await reap(done, pending, signaled)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/avi/scylla-maint/./test.py", line 418, in reap
result = coro.result()
File "/home/avi/scylla-maint/test/pylib/suite/python.py", line 143, in run
return await super().run(test, options)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/avi/scylla-maint/test/pylib/suite/base.py", line 216, in run
await test.run(options)
File "/home/avi/scylla-maint/test/pylib/suite/topology.py", line 48, in run
async with get_cluster_manager(self.uname, self.suite.clusters, str(self.suite.log_dir)) as manager:
~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib64/python3.13/contextlib.py", line 221, in __aexit__
await anext(self.gen)
File "/home/avi/scylla-maint/test/pylib/scylla_cluster.py", line 2006, in get_cluster_manager
await manager.stop()
File "/home/avi/scylla-maint/test/pylib/scylla_cluster.py", line 1539, in stop
await self.clusters.put(self.cluster, is_dirty=True)
File "/home/avi/scylla-maint/test/pylib/pool.py", line 104, in put
await self.destroy(obj)
File "/home/avi/scylla-maint/test/pylib/suite/python.py", line 65, in recycle_cluster
srv.log_file.close()
^^^^^^^^^^^^
AttributeError: 'ScyllaServer' object has no attribute 'log_file'
```
Closesscylladb/scylladb#24885
test/cqlpy/README.md explains how to run the cqlpy tests against
Cassandra, and mentions that if you don't have "nodetool" in your path
you need to set the NODETOOL variable. However, when giving a simple
example how to use the run-cassandra script, we forgot to remind the
user to set NODETOOL in addition to CASSANDRA, causing confusion for
users who didn't know why tests were failing.
So this patch fixes the section in test/cqlpy/README.md with the
run-cassandra example to also set the NODETOOL environment variable,
not just CASSANDRA.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closesscylladb/scylladb#25051
Audit tests are vulnerable to noise from LOGIN queries (because AUTH
audit logs can appear at any time). Most tests already use the
`filter_out_noise` mechanism to remove this noise, but tests
focused on AUTH verification did not, leading to sporadic failures.
This change adds a filter to ignore AUTH logs generated by the default
"cassandra" user, so tests only verify logs from the user created
specifically for each test.
Additionally, this PR:
- Adds missing `nonlocal new_rows` statement that prevented some checks from being called
- Adds a testcase for audit logs of `cassandra` user
Fixes: https://github.com/scylladb/scylladb/issues/25069
Better backport those test changes to 2025.3. 2025.2 and earlier don't have `./cluster/dtest/audit_test.py`.
Closesscylladb/scylladb#25111
* github.com:scylladb/scylladb:
test: audit: add cassandra user test case
test: audit: ignore cassandra user audit logs in AUTH tests
test: audit: change names of `filter_out_noise` parameters
test: audit: add missing `nonlocal new_rows` statement
Instead of requesting it from gms code, create it "by hand" with the
help of get_disabled_features_from_db_config() method. This is how other
services are configured by main/tools/testing code.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Audit tests use the `filter_out_noise` function to remove noise from
audit logs generated by user authentication. As a result, none of the
existing tests covered audit logs for the default `cassandra` user.
This change adds a test case for that user.
Refs: scylladb/scylladb#25069
Audit tests are vulnerable to noise from LOGIN queries (because AUTH
audit logs can appear at any time). Most tests already use the
`filter_out_noise` mechanism to remove this noise, but tests
focused on AUTH verification did not, leading to sporadic failures.
This change adds a filter to ignore AUTH logs generated by the default
"cassandra" user, so tests only verify logs from the user created
specifically for each test.
Fixes: scylladb/scylladb#25069
This is a refactoring commit that changes the names of the parameters
of the `filter_out_noise` function, as well as names of related
variables. The motiviation for the change is introduction of more
complex filtering logic in next commit of this patch series.
Refs: scylladb/scylladb#25069
The variable `new_rows` was not updated by the inner function
`is_number_of_new_rows_correct` because the `nonlocal new_rows`
statement was missing. As a result, `sorted_new_rows` was empty and
certain checks were skipped.
This change:
- Introduces the missing `nonlocal new_rows` declaration
- Adds an assertion verifying that the number of new rows matches
the expected count
- Fixes the incorrect variable name in the lambda used for row sorting
As requested in #22114, moved the files and fixed other includes and build system.
Moved files:
- interval.hh
- Map_difference.hh
Fixes: #22114
This is a cleanup, no need to backport
Closesscylladb/scylladb#25095
The set of columns of a CDC log table should be managed automatically
by Scylla, and the user should not have the ability to manipulate them
directly. That could lead to disastrous consequences such as a
segmentation fault.
In this commit, we're restricting those operations. We also provide two
validation tests.
One of the existing tests had to be adjusted as it modified the type
of a column in a CDC log table. Since the test simply verifies that
the user has sufficient permissions to perform `ALTER TABLE` on the log
table, the test is still valid.
Fixesscylladb/scylladb#24643
Backport: we should backport the change to all affected
branches to prevent the consequences that may affect the user.
Closesscylladb/scylladb#25008
* github.com:scylladb/scylladb:
cdc: Forbid altering columns of inactive CDC log table
cdc: Forbid altering columns of CDC log tables directly
`protocol_exception` is thrown in several places. This has become a performance issue, especially when starting/restarting a server. To alleviate this issue, throwing the exception has to be replaced with returning it as a result or an exceptional future.
This PR replaces throws in the `transport/server` module. This is achieved by using result_with_exception, and in some places, where suitable, just by creating and returning an exceptional future.
There are four commits in this PR. The first commit introduces tests in `test/cqlpy`. The second commit refactors transport server `handle_error` to not rethrow exceptions. The third commit refactors reusable buffer writer callbacks. The fourth commit replaces throwing `protocol_exception` to returning it.
Based on the comments on an issue linked in https://github.com/scylladb/scylladb/issues/24567, the main culprit from the side of protocol exceptions is the invalid protocol version one, so I tested that exception for performance.
In order to see if there is a measurable difference, a modified version of `test_protocol_version_mismatch` Python is used, with 100'000 runs across 10 processes (not threads, to avoid Python GIL). One test run consisted of 1 warm-up run and 5 measured runs. First test run has been executed on the current code, with throwing protocol exceptions. Second test urn has been executed on the new code, with returning protocol exceptions. The performance report is in https://github.com/scylladb/scylladb/pull/24738#issuecomment-3051611069. It shows ~10% gains in real, user, and sys time for this test.
Testing
Build: `release`
Test file: `test/cqlpy/test_protocol_exceptions.py`
Test name: `test_protocol_version_mismatch` (modified for mass connection requests)
Test arguments:
```
max_attempts=100'000
num_parallel=10
```
Throwing `protocol_exception` results:
```
real=1:26.97 user=10:00.27 sys=2:34.55 cpu=867%
real=1:26.95 user=9:57.10 sys=2:32.50 cpu=862%
real=1:26.93 user=9:56.54 sys=2:35.59 cpu=865%
real=1:26.96 user=9:54.95 sys=2:32.33 cpu=859%
real=1:26.96 user=9:53.39 sys=2:33.58 cpu=859%
real=1:26.95 user=9:56.85 sys=2:34.11 cpu=862% # average
```
Returning `protocol_exception` as `result_with_exception` or an exceptional future:
```
real=1:18.46 user=9:12.21 sys=2:19.08 cpu=881%
real=1:18.44 user=9:04.03 sys=2:17.91 cpu=869%
real=1:18.47 user=9:12.94 sys=2:19.68 cpu=882%
real=1:18.49 user=9:13.60 sys=2:19.88 cpu=883%
real=1:18.48 user=9:11.76 sys=2:17.32 cpu=878%
real=1:18.47 user=9:10.91 sys=2:18.77 cpu=879% # average
```
This PR replaced `transport/server` throws of `protocol_exception` with returns. There are a few other places where protocol exceptions are thrown, and there are many places where `invalid_request_exception` is thrown. That is out of scope of this single PR, so the PR just refs, and does not resolve issue #24567.
Refs: #24567
This PR improves performance in cases when protocol exceptions happen, for example during connection storms. It will require backporting.
Closesscylladb/scylladb#24738
* github.com:scylladb/scylladb:
test/cqlpy: add cpp exception metric test conditions
transport/server: replace protocol_exception throws with returns
utils/reusable_buffer: accept non-throwing writer callbacks via result_with_exception
transport/server: avoid exception-throw overhead in handle_error
test/cqlpy: add protocol_exception tests
When CDC becomes disabled on the base table, the CDC log table
still exsits (cf. scylladb/scylladb@adda43edc7).
If it continues to exist up to the point when CDC is re-enabled
on the base table, no new log table will be created -- instead,
the old olg table will be *re-attached*.
Since we want to avoid situations when the definition of the log
table has become misaligned with the definition of the base table
due to actions of the user, we forbid modifying the set of columns
or renaming them in CDC log tables, even when they're inactive.
Validation tests are provided.
in the CDC log transformer, when creating a CDC mutation based on some
base table mutation, for each value of a base column we set the value in
the CDC column with the same name.
When looking up the column in the CDC schema by name, we may get a null
pointer if a column by that name is not found. This shouldn't happen
normally because the base schema and CDC schema should be compatible,
and for each base column there should be a CDC column with the same
name.
However, there are scenarios where the base schema and CDC schema are
incompatible for a short period of time when they are being altered.
When a base column is being added or dropped, we could get a base
mutation with this column set, and then the CDC transformer picks up the
latest CDC schema which doesn't have this column.
If such thing happens, we fix the code to throw an exception instead of
crashing on null pointer dereference. Currently we don't have a safer
approach to handle this, but this might be changed in the future. The
other alternative is dropping that data silently which we prefer not to
do.
Throwing an error is acceptable because this scenario most likely
indicates this behavior by the user:
* The user adds a new column, and start writing values to the column
before the ALTER is complete. or,
* The user drops a column, and continues writing values to the column
while it's being dropped.
Both cases might as well fail with an error because the column is not
found in the base table.
Fixesscylladb/scylladb#24952
backport needed - simple fix for a node crash
Closesscylladb/scylladb#24986
* github.com:scylladb/scylladb:
test: cdc: add test_cdc_with_alter
cdc: throw error if column doesn't exist
We adjust test_create_role_with_hashed_password_authorization to work
with both Scylla and Cassandra. For some reason (probably a bug),
Cassandra requires that the `LOGIN` property of a role come before
the password.
Cassandra doesn't use service levels, and it doesn't include auth
in the output of `DESCRIBE SCHEMA`. It doesn't support the form of the
statement `... WITH PASSWORDS`. UDFs in Cassandra don't support Lua.
That's why the test didn't work against Cassandra.
In this commit, we adjust it to work with both Scylla and Cassandra.
Tests verifying that auth and service levels are part of the output
of `DESCRIBE SCHEMA` were not marked as `scylla_only` when they were
written, but they're a feature only Scylla has. Because of that, let's
mark them with `scylla_only` so they're not run against Cassandra to
avoid unnecessary failures. We also provide a short explanation for
each test why it's marked that way.
Tested code paths should not throw exceptions. `scylla_reactor_cpp_exceptions`
metric is used. This is a global metric. To address potential test flakiness,
each test runs multiple times:
- `run_count = 100`
- `cpp_exception_threshold = 10`
If a change in the code introduced an exception, expectation is that the number
of registered exceptions will be > `cpp_exception_threshold` in `run_count` runs.
In which case the test fails.
Make make_bytes_ostream and make_fragmented_temporary_buffer accept
writer callbacks that return utils::result_with_exception instead of
forcing them to throw on error. This lets callers propagate failures
by returning an error result rather than throwing an exception.
Introduce buffer_writer_for, bytes_ostream_writer, and fragmented_buffer_writer
concepts to simplify and document the template requirements on writer callbacks.
This patch does not modify the actual callbacks passed, except for the syntax
changes needed for successful compilation, without changing the logic.
Refs: #24567
Add a helper to fetch scylla_transport_cql_errors_total{type="protocol_error"} counter
from Scylla's metrics endpoint. These metrics are used to track protocol error
count before and after each test.
Add cql_with_protocol context manager utility for session creation with parameterized
protocol_version value. This is used for testing connection establishment with
different protocol versions, and proper disposal of successfully established sessions.
The tests cover two failure scenarios:
- Protocol version mismatch in test_protocol_version_mismatch which tests both supported
and unsupported protocol version
- Malformed frames via raw socket in _protocol_error_impl, used by several test functions,
and also test_no_protocol_exceptions test to assert that the error counters never decrease
during test execution, catching unintended metric resets
Refs: #24567
This is a refactoring patch in preparation for BTI indexes. It contains no functional changes (or at least it's not intended to).
In this patch, we modify the sstable readers to use index readers through a new virtual `abstract_index_readers` interface.
Later, we will add BTI indexes which will also implement this interface.
This interface contains the methods of `index_reader` which are needed by sstable readers, and leaves out all other methods, such as `current_clustered_cursor`.
Not all methods of this interface will be implementable by a trie-based index later. For example, a trie-based index can't provide a reliable `get_partition_key()`, because — unlike the current index — it only stores partition keys for partitions which have a row index. So the interface will have to be further restricted later. We don't do that in this patch because that will require changes to sstable reader logic, and this patch is supposed to only include cosmetic changes.
No backports needed, this is a preparation for new functionality.
Closesscylladb/scylladb#25000
* github.com:scylladb/scylladb:
sstables: add sstable::make_index_reader() and use where appropriate
sstables/mx: in readers, use abstract_index_reader instead of index_reader
sstables: in validate(), use abstract_index_reader instead of index_reader where possible
test/lib/index_reader_assertions: accept abstract_index_reader instead of index_reader
sstables/index_reader: introduce abstract_index_reader
sstables/index_reader: extract a prefetch_lower_bound() method
This PR adds a way for custom indexes to decide whether a view should be created for them, as for the vector_index the view is not needed, because we store it in the external service. To allow this, custom logic for describing indexes using custom classes was added (as it used to depend on the view corresponding to an index).
Fixes: VECTOR-10
Closesscylladb/scylladb#24438
* github.com:scylladb/scylladb:
custom_index: do not create view when creating a custom index
custom_index: refactor describe for custom indexes
custom_index: remove unneeded duplicate of a static string
If we add multiple index implementations, users of index readers won't
easily know which concrete index reader type is the right one to construct.
We also don't want pieces of code to depend on functionality specific to
certain concrete types, if that's not necessary.
So instead of constructing the readers by themselves, they can use a helper
function, which will return an abstract (virtual) index reader.
This patch adds such a function, as a method of `sstable`.
