Commit Graph

19 Commits

Author SHA1 Message Date
Radosław Cybulski
c5ed6b22ae alternator: add CHILD_SHARDS filtering
Add a `CHILD_SHARDS` filter to `DescribeStream` command.
When used, user need to pass a parent stream shard id as
json's ShardFilter.ShardId field. DescribeStream will
then return only list of stream shards, that are direct
descendants of passed parent stream shard.

Each stream shard cover a consecutive part of token space.
A stream shard Q is considered to be a child of stream shard W,
when at least one token belongs to token spaces from both streams.
The filtering algorithm itself is somewhat complicated - more details
in comments in streams.cc.

CHILD_SHARDS is a Amazon's functionality and is required by KCL.

Add unit tests.

Fixes: #25160

Closes scylladb/scylladb#28189
2026-04-16 18:27:55 +03:00
Radosław Cybulski
4b984212ba alternator: improve parsing / generating of StreamArn parameter
Previously Alternator, when emit Amazon's ARN would not stick to the
standard. After our attempt to run KCL with scylla we discovered few
issues.

Amazon's ARN looks like this:

arn:partition:service:region:account-id:resource-type/resource-id

for example:

arn:aws:dynamodb:us-west-2:111122223333:table/TestTable/stream/2015-05-11T21:21:33.291

KCL checks for:
- ARN provided from Alternator calls must fit with basic Amazon's ARN
  pattern shown above,
- region constisting only of lower letter alphabets and `-`, no
  underscore character
- account-id being only digits (exactly 12)
- service being `dynamodb`
- partition starting with `aws`

The patch updates our code handling ARNs to match those findings.

1. Split `stream_arn` object into `stream_arn` - ARN for streams only and
`stream_shard_id` - id value for stream shards. The latter receives original
implementation. The former emits and parses ARN in a Amazon style.
 for example:
2. Update new `stream_arn` class to encode keyspace and table together
separating them by `@`. New ARN looks like this:

arn:aws:dynamodb:us-east-1:000000000000:table/TestKeyspace@TestTable/stream/2015-05-11T21:21:33.291

3. hardcode `dynamodb` as service, `aws` as partition, `us-east-1` as
   region and `000000000000` as account-id (must have 12 digits)
4. Update code handling ARNs for tags manipulation to be able to parse
   Amazon's style ARNs. Emiting code is left intact - the parser is now
   capable of parsing both styles.
5. Added unit tests.

Fixes #28350
Fixes: SCYLLADB-539
Fixes: #28142

Closes scylladb/scylladb#28187
2026-04-14 18:07:05 +03:00
Avi Kivity
0ae22a09d4 LICENSE: Update to version 1.1
Updated terms of non-commercial use (must be a never-customer).
2026-04-12 19:46:33 +03:00
Radosław Cybulski
fe8117feee alternator: fix shard's parent calculation for vnodes
Fix an invalid condition, when searching for a parent shard, when table
is based on vnodes. Shards have associated with them `last token` -
token, than marks the end of the range of tokens they consume (inclusive).
An additional assumptions are whole token space is used and
(for vnodes) token space wraps around.

Previously code looked like this:
    auto pid = std::upper_bound(..., [](const dht::token& t, const cdc::stream_id& id) {
                    return t < id.token();
    });
    if (pid != pids.begin()) {
        pid = std::prev(pid);
    }

An `upper_bound` call with `t < id.token()` means it is looking for
an iterator, for which value `t < id.token()` changed to true,
which effectively means a position, where iterator is bigger
then searched value. Then we move iterator backward once if possible.
Assuming token space <-2, 2> and parents [0, 2], when we search for:
- -1 -> we will get 0, it's first, so we can't move backward, so 0 (ok)
- 0 -> we will get 2, it's not first, so we go back and we return 0 (ok)
- 1 -> we will get 2, it's not first, so we go back and we return 0
      (not ok - should be 2)

The fix is to replace it with `std::lower_bound` and remove conditional
backward motion. Since we've a guarantees that whole token space is used
if `std::lower_bound` ends with `end()` value, then we have a wrap
around case and we need to pick `begin()` as result.

Fixes #28354
Fixes: SCYLLADB-537

Closes scylladb/scylladb#28382
2026-03-11 14:51:42 +02:00
Petr Gusev
889d7782ed treewide: use coroutine::maybe_yield in coroutines
It's more efficient since coroutine::maybe_yield returns
a lightweight struct (awaitable), not the future.

Closes scylladb/scylladb#28101
2026-01-12 10:38:47 +01:00
Szymon Malewski
b75c6c9ef7 alternator: adds expression cache implementation
Every expression in Alternator's requests is parsed from string to adequate structure.
This patch implements a caching structure (input expression strings mapping to parsed 'template' structures), which will be used for handling requests in following commits.
If the reqested expression is valid (parsable) the cache will always return a value - if it is not already in the cache it will be created and stored.
The cache has limited (live configurable) size - when it is reached, the least recently used entry is removed.
The copy of the template in cache is returned - individual instances still need to be resolved (placeholders substituted with names and values).
Invalid requests will have no effect on the cache - the parser throws an exception.
Caching is implemented for all expression types. Internally it is based on helper structure `lru_string_map`.
Basic metrics (total count of hits and misses for each expression type and number of evictions) are implemented.
Metrics are used in boost unit tests.
2025-09-28 04:27:44 +02:00
Szymon Malewski
be159acc03 alternator/expressions: fix single value condition expression parsing
Primitive conditions usually use operator with two or more values.
The only case of a "single value" condition is a function call -
DynamoDB does not accept other general values (i.e., attribute or value references).
In Alternator single general value was parsed as correct and only failed
later when the calculated value ended up to not be a boolean.
This works, but not when attribute or value actually is boolean.

What is more, when a parsed (but not resolved) expression is cached, this invalid expression could pollute cache.
This would be also the only case where the same string can be parsed both as a condition and a projection expression.

The issue is fixed by explicitly checking this case at primitive condition parsing.
Updated test confirms consistence between Alternator and DynamoDB.

Fixes #25855.
2025-09-28 04:06:00 +02:00
Avi Kivity
29032213c8 test: avoid #include <boost/test/included/...>
The boost/test/included/... directory is apparently internal and not
intended for user consumption.

Including it caused a One-Definition-Rule violation, due to
boost/test/impl/unit_test_parameters.ipp containing code like this:

```c++
namespace runtime_config {

// UTF parameters
std::string btrt_auto_start_dbg    = "auto_start_dbg";
std::string btrt_break_exec_path   = "break_exec_path";
std::string btrt_build_info        = "build_info";
std::string btrt_catch_sys_errors  = "catch_system_errors";
std::string btrt_color_output      = "color_output";
std::string btrt_detect_fp_except  = "detect_fp_exceptions";
std::string btrt_detect_mem_leaks  = "detect_memory_leaks";
std::string btrt_list_content      = "list_content";
```

This is defining variables in a header, and so can (and in fact does)
create duplicate variable definitions, which later cause trouble.

So far, we were protected from this trouble by -fvisibility=hidden, which
caused the duplicate definitions to be in fact not duplicate.

Fix this by correcting the include path away from <boost/test/included/>.

Closes scylladb/scylladb#26161
2025-09-22 15:26:06 +03:00
Szymon Malewski
776f90e2f8 alternator/expressions.g: Fix antlr3 missing token leak
This patch overrides the antlr3 function that allocates the missing
tokens that would eventually leak. The override stores these tokens in
a vector, ensuring memory is freed whenever the parser is destroyed.
Solution is copied from CQL implementation.

A unit test to reproduce the issue is added - leak would be reported
by ASAN, when running this test in debug mode - the test passed but
the leak is discovered when the test file exits.

Fixes #25878

Closes scylladb/scylladb#25930
2025-09-17 13:05:24 +03:00
Avi Kivity
f3eade2f62 treewide: relicense to ScyllaDB-Source-Available-1.0
Drop the AGPL license in favor of a source-available license.
See the blog post [1] for details.

[1] https://www.scylladb.com/2024/12/18/why-were-moving-to-a-source-available-license/
2024-12-18 17:45:13 +02:00
Kefu Chai
3e84d43f93 treewide: use seastar::format() or fmt::format() explicitly
before this change, we rely on `using namespace seastar` to use
`seastar::format()` without qualifying the `format()` with its
namespace. this works fine until we changed the parameter type
of format string `seastar::format()` from `const char*` to
`fmt::format_string<...>`. this change practically invited
`seastar::format()` to the club of `std::format()` and `fmt::format()`,
where all members accept a templated parameter as its `fmt`
parameter. and `seastar::format()` is not the best candidate anymore.
despite that argument-dependent lookup (ADT for short) favors the
function which is in the same namespace as its parameter, but
`using namespace` makes `seastar::format()` more competitive,
so both `std::format()` and `seastar::format()` are considered
as the condidates.

that is what is happening scylladb in quite a few caller sites of
`format()`, hence ADT is not able to tell which function the winner
in the name lookup:

```
/__w/scylladb/scylladb/mutation/mutation_fragment_stream_validator.cc:265:12: error: call to 'format' is ambiguous
  265 |     return format("{} ({}.{} {})", _name_view, s.ks_name(), s.cf_name(), s.id());
      |            ^~~~~~
/usr/bin/../lib/gcc/x86_64-redhat-linux/14/../../../../include/c++/14/format:4290:5: note: candidate function [with _Args = <const std::basic_string_view<char> &, const seastar::basic_sstring<char, unsigned int, 15> &, const seastar::basic_sstring<char, unsigned int, 15> &, const utils::tagged_uuid<table_id_tag> &>]
 4290 |     format(format_string<_Args...> __fmt, _Args&&... __args)
      |     ^
/__w/scylladb/scylladb/seastar/include/seastar/core/print.hh:143:1: note: candidate function [with A = <const std::basic_string_view<char> &, const seastar::basic_sstring<char, unsigned int, 15> &, const seastar::basic_sstring<char, unsigned int, 15> &, const utils::tagged_uuid<table_id_tag> &>]
  143 | format(fmt::format_string<A...> fmt, A&&... a) {
      | ^
```

in this change, we

change all `format()` to either `fmt::format()` or `seastar::format()`
with following rules:
- if the caller expects an `sstring` or `std::string_view`, change to
  `seastar::format()`
- if the caller expects an `std::string`, change to `fmt::format()`.
  because, `sstring::operator std::basic_string` would incur a deep
  copy.

we will need another change to enable scylladb to compile with the
latest seastar. namely, to pass the format string as a templated
parameter down to helper functions which format their parameters.
to miminize the scope of this change, let's include that change when
bumping up the seastar submodule. as that change will depend on
the seastar change.

Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
2024-09-11 23:21:40 +03:00
Nadav Har'El
e74f69bb56 alternator: unit test for number magnitude and precision function
In the previous patch we added a limit in Alternator for the magnitude
and precision of numbers, based on a function get_magnitude_and_precision
whose implementation was, unfortunately, rather elaborate and delicate.

Although we did add in the previous patches some end-to-end tests which
confirmed that the final decision made based on this function, to accept or
reject numbers, was a correct decision in a few cases, such an elaborate
function deserves a separate unit test for checking just that function
in isolation. In fact, this unit tests uncovered some bugs in the first
implementation of get_magnitude_and_precision() which the other tests
missed.

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
2023-05-02 11:04:05 +03:00
Avi Kivity
fcb8d040e8 treewide: use Software Package Data Exchange (SPDX) license identifiers
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
2022-01-18 12:15:18 +01:00
Avi Kivity
d3f8148807 utils: untie rjson.hh from base64.hh
base64.hh pulls in the huge rjson.hh, so if someone just wants
a base64 codec they have to pull in the entire rapidjson library.

Move the json related parts of base64.hh to rjson.hh and adjust
includes and namespaces.

In practice it doesn't make much difference, as all users of base64
appear to want json too. But it's cleaner not to mix the two.

Closes #9433
2021-10-05 12:57:54 +02:00
Piotr Dulikowski
5a0942a0f8 utils,alternator: move base64 code from alternator to utils
The base64 encoding/decoding functions will be used for serialization of
hint sync point descriptions. Base64 format is not specific to
Alternator, so it can be moved to utils.
2021-08-09 09:24:36 +02:00
Avi Kivity
a55b434a2b treewide: extent copyright statements to present day 2021-06-06 19:18:49 +03:00
Piotr Sarna
223a59c09c test: make rjson allocator test working in sanitize mode
Following Nadav's advice, instead of ignoring the test
in sanitize/debug modes, the allocator simply has a special path
of failing sufficiently large allocation requests.
With that, a problem with the address sanitizer is bypassed
and other debug mode sanitizers can inspect and check
if there are no more problems related to wrapping the original
rapidjson allocator.

Closes #8539
2021-05-20 00:42:47 +03:00
Piotr Sarna
83a45adbb7 test: add a test for rjson allocation
The test cases check if the new rjson allocator throws
when it fails to allocate/reallocate memory.
2021-04-22 15:59:13 +02:00
Piotr Sarna
dfd1ea6b92 test: rename alternator_base64_test to alternator_unit_test
With the more generic name, I would no longer feel bad adding
non-base64 test cases to it.
2021-04-21 14:26:40 +02:00