This is to define the API sstable needs from underlying storage. When implementing object-storage backend it will need to implement those. The API looks like
future<> snapshot(const sstable& sst, sstring dir, absolute_path abs) const;
future<> quarantine(const sstable& sst, delayed_commit_changes* delay);
future<> move(const sstable& sst, sstring new_dir, generation_type generation, delayed_commit_changes* delay);
void open(sstable& sst, const io_priority_class& pc); // runs in async context
future<> wipe(const sstable& sst) noexcept;
future<file> open_component(const sstable& sst, component_type type, open_flags flags, file_open_options options, bool check_integrity);
It doesn't have "list" or alike, because it's not a method of an individual sstable, but rather the one from sstables_manager. It will come as separate PR.
Closes#12217
* github.com:scylladb/scylladb:
sstable, storage: Mark dir/temp_dir private
sstable: Remove get_dir() (well, almost)
sstable: Add quarantine() method to storage
sstable: Use absolute/relative path marking for snapshot()
sstable: Remove temp_... stuff from sstable
sstable: Move open_component() on storage
sstable: Mark rename_new_sstable_component_file() const
sstable: Print filename(type) on open-component error
sstable: Reorganize new_sstable_component_file()
sstable: Mark filename() private
sstable: Introduce index_filename()
tests: Disclosure private filename() calls
sstable: Move wipe_storage() on storage
sstable: Remove temp dir in wipe_storage()
sstable: Move unlink parts into wipe_storage
sstable: Remove get_temp_dir()
sstable: Move write_toc() to storage
sstable: Shuffle open_sstable()
sstable: Move touch_temp_dir() to storage
sstable: Move move() to storage
sstable: Move create_links() to storage
sstable: Move seal_sstable() to storage
sstable: Tossing internals of seal_sstable()
sstable: Move remove_temp_dir() to storage
sstable: Move create_links_common() to storage
sstable: Move check_create_links_replay() to storage
sstable: Remove one of create_links() overloads
sstable: Remove create_links_and_mark_for_removal()
sstable: Indentation fix after prevuous patch
sstable: Coroutinize create_links_common()
sstable: Rename create_links_common()'s "dir" argument
sstable: Make mark_for_removal bool_class
sstable, table: Add sstable::snapshot() and use in table::take_snapshot
sstable: Move _dir and _temp_dir on filesystem_storage
sstable: Use sync_directory() method
test, sstable: Use component_basename in test
sstables: Move read_{digest|checksum} on sstable
Recently, the pytest script shipped by Fedora started invoking python
with the `-s` flag, which disables python considering user site
packages. This caused problems for our tests which install the cassandra
driver in the user site packages. This was worked around in e5e7780f32
by providing our own pytest interposer launcher script which does not
pass the above mentioned flag to python. Said patch fixed test.py but
not the run.py in cql-pytest. So if the cql-pytest suite is ran via
test.py it works fine, but if it is invoked via the run script, it fails
because it cannot find the cassandra driver. This patch patches run.py
to use our own pytest launcher script, so the suite can be run via the
run script as well.
Since run.py is shared with the alternator pytest suite, this patch also
fixes said test suite too.
Closes#12253
This PR fixes several bugs related to handling of non-full
clustering keys.
One is in trim_clustering_row_ranges_to(), which is broken for non-full keys in reverse
mode. It will trim the range to position_in_partition_view::after_key(full_key) instead of
position_in_partition_view::before_key(key), hence it will include the
key in the resulting range rather than exclude it.
Fixes#12180
after_key() was creating a position which is after all keys prefixed
by a non-full key, rather than a position which is right after that
key.
This will issue will be caught by cql_query_test::test_compact_storage
in debug mode when mutation_partition_v2 merging starts inserting
sentinels at position after_key() on preemption.
It probably already causes problems for such keys as after_key() is used
in various parts in the read path.
Refs #1446Closes#12234
* github.com:scylladb/scylladb:
position_in_partition: Make after_key() work with non-full keys
position_in_partition: Introduce before_key(position_in_partition_view)
db: Fix trim_clustering_row_ranges_to() for non-full keys and reverse order
types: Fix comparison of frozen sets with empty values
There's a bunch of helpers around XFS-specific temp-dir sitting in
publie sstable part. Drop it altogether, no code needs it for real.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The sstable::filename() is going to become private method. Lots of tests
call it, but tests do call a lot of other sstable private methods,
that's OK. Make the sstable::filename() yet another one of that kind in
advance.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
This method initiates the sstable creation. Effectively it's the first
step in sstable creation transaction implemented on top of rename()
call. Thus this method is moved onto storage under respective name.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
When an sstable is prepared to be written on disk the .write_toc() is
called on it which created temporary toc file. Prior to this, the writer
code calls generate_toc() to collect components on the sstable.
This patch adds the .open_sstable() API call that does both. This
prepares the write_toc() part to be moved to storage, because it's not
just "write data into TOC file", it's the first step in transaction
implemeted on top of rename()s.
The test need care -- there's rewrite_toc_without_scylla_component()
thing in utils that doesn't want the generate_toc() part to be called.
It's not patched here and continues calling .write_toc().
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
This method is currently used in two places: sstable::snapshot() and
sstable::seal_sstable(). The latter additionally touches the target
backup/ subdir.
This patch moves the whole thing on storage and adds touch for all the
cases. For snapshots this might be excessive, but harmless.
Tests get their private-disclosure way to access sstable._storage in
few places to call create_links directly.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
There are two of them -- one API call and the other one that just
"seals" it. The latter one also changes the _marked_for_deletion bit on
the sstable.
This patch makes the latter method prepared to be moved onto storage,
because sealing means comitting TOC file on disk with the help of rename
system call which is purely storage thing.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Those two fields define the way sstable is stored as collection of
on-disk files. First step towards making the storage access abstract is
in moving the paths onto filesystem_storage embedded class.
Both are made public for now, the rest of the code is patched to access
them via _storage.<smth>. The rest of the set moves parts of sstable::
methods into the filesystem_storage, then marks the paths private.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
One case gets full sstable datafile path to get the basename from it.
There's already the basename helper on the class sstable.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Now, with a44ca06906, is_normal_token_owner that replaced is_member
does not rely anymore on the pending status
of endpoints in topology.
With that we can get rid of this state and just keep all endpoints we know about in the topology.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Closes#12294
* github.com:scylladb/scylladb:
topology: get rid of pending state
topology: debug log update and remove endpoint
This fixes a long standing bug related to handling of non-full
clustering keys, issue #1446.
after_key() was creating a position which is after all keys prefixed
by a non-full key, rather than a position which is right after that
key.
This will issue will be caught by cql_query_test::test_compact_storage
in debug mode when mutation_partition_v2 merging starts inserting
sentinels at position after_key() on preemption.
It probably already causes problems for such keys.
Sometimes a single modification to a base partition requires updates to
a large number of view rows. A common example is deletion of a base
partition containing many rows. A large BATCH is also possible.
To avoid large allocations, we split the large amount of work into
batch of 100 (max_rows_for_view_updates) rows each. The existing code
assumed an empty result from one of these batches meant that we are
done. But this assumption was incorrect: There are several cases when
a base-table update may not need a view update to be generated (see
can_skip_view_updates()) so if all 100 rows in a batch were skipped,
the view update stopped prematurely. This patch includes two tests
showing when this bug can happen - one test using a partition deletion
with a USING TIMESTAMP causing the deletion to not affect the first
100 rows, and a second test using a specially-crafed large BATCH.
These use cases are fairly esoteric, but in fact hit a user in the
wild, which led to the discovery of this bug.
The fix is fairly simple: To detect when build_some() is done it is no
longer enough to check if it returned zero view-update rows; Rather,
it explicitly returns whether or not it is done as an std::optional.
The patch includes several tests for this bug, which pass on Cassandra,
failed on Scylla before this patch, and pass with this patch.
Fixes#12297.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#12305
This PR implements two things:
* Getting the value of a conjunction of elements separated by `AND` using `expr::evaluate`
* Preparing conjunctions using `prepare_expression`
---
`NULL` is treated as an "unkown value" - maybe `true` maybe `false`.
`TRUE AND NULL` evaluates to `NULL` because it might be `true` but also might be `false`.
`FALSE AND NULL` evaluates to `FALSE` because no matter what value `NULL` acts as, the result will still be `FALSE`.
Unset and empty values are not allowed.
Usually in CQL the rule is that when `NULL` occurs in an operation the whole expression becomes `NULL`, but here we decided to deviate from this behavior.
Treating `NULL` as an "unkown value" is the standard SQL way of handing `NULLs` in conjunctions.
It works this way in MySQL and Postgres so we do it this way as well.
The evaluation short-circuits. Once `FALSE` is encountered the function returns `FALSE` immediately without evaluating any further elements.
It works this way in Postgres as well, for example:
`SELECT true AND NULL AND 1/0 = 0` will throw a division by zero error,
but `SELECT false AND 1/0 = 0` will successfully evaluate to `FALSE`.
Closes#12300
* github.com:scylladb/scylladb:
expr_test: add unit tests for prepare_expression(conjunction)
cql3: expr: make it possible to prepare conjunctions
expr_test: add tests for evaluate(conjunction)
cql3: expr: make it possible to evaluate conjunctions
Now, with a44ca06906,
is_normal_token_owner that replaced is_member
does not rely anymore on the pending status
of endpoints in topology.
With that we can get rid of this state and just keep
all endpoints we know about in the topology.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
The Host ID now uniquely identifies a node (we no longer steal it during
node replace) and Raft is still experimental. We can reuse the Host ID
of a node as its Raft ID. This will allow us to remove and simplify a
lot of code.
With this we can already remove some dead code in this commit.
This patch includes a translation of two more test files from
Cassandra's CQL unit test directory cql3/validation/operations.
All tests included here pass on Cassandra. Several test fail on Scylla
and are marked "xfail". These failures discovered two previously-unknown
bugs:
#12243: Setting USING TTL of "null" should be allowed
#12247: Better error reporting for oversized keys during INSERT
And also added reproducers for two previously-known bugs:
#3882: Support "ALTER TABLE DROP COMPACT STORAGE"
#6447: TTL unexpected behavior when setting to 0 on a table with
default_time_to_live
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#12248
We recently (commit 6a5d9ff261) started
to use std::source_location instead of std::experimental::source_location.
However, this does not work on clang 14, because libc++ 12's
<source_location> only works if __builtin_source_location, and that is
not available on clang 14.
clang 15 is just three months old, and several relatively-recent
distributions still carry clang 14 so it would be nice to support it
as well.
So this patch adds a trivial compatibility header file, which, when
included and compiled with clang 14, it aliases the functional
std::experimental::source_location to std::source_location.
It turns out it's enough to include the new header file from three
headers that included <source_location> - I guess all other uses
of source_location depend on those header files directly or indirectly.
We may later need to include the compatibility header file in additional
places, bug for now we don't.
Refs #12259
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#12265
This PR adds server-side `DESCRIBE` statement, which is required in latest cqlsh version.
The only change from the user perspective is the `DESC ...` statement can be used with cqlsh version >= 6.0. Previously the statement was executed from client side, but starting with Cassandra 4.0 and cqlsh 6.0, execution of describe was moved to server side, so the user was unable to do `DESC ...` with Scylla and cqlsh 6.0.
Implemented describe statements:
- `DESC CLUSTER`
- `DESC [FULL] SCHEMA`
- `DESC [ONLY] KEYSPACE`
- `DESC KEYSPACES/TYPES/FUNCTIONS/AGGREGATES/TABLES`
- `DESC TYPE/FUNCTION/AGGREGATE/MATERIALIZED VIEW/INDEX/TABLE`
- `DESC`
[Cassandra's implementation for reference](https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/cql3/statements/DescribeStatement.java)
Changes in this patch:
- cql3::util: added `single_quite()` function
- added `data_dictionary::keyspace_element` interface
- implemented `data_dictionary::keyspace_element` for:
- keyspace_metadata,
- UDT, UDF, UDA
- schema
- cql3::functions: added `get_user_functions()` and `get_user_aggregates()` to get all UDFs/UDAs in specified keyspace
- data_dictionary::user_types_metadata: added `has_type()` function
- extracted `describe_ring()` from storage_service to standalone helper function in `locator/util.hh`
- storage_proxy: added `describe_ring()` (implemented using helper function mentioned above)
- extended CQL grammar to handle describe statement
- increased version in `version.hh` to 4.0.0, so cqlsh will use server-side describe statement
Referring: https://github.com/scylladb/scylla/issues/9571, https://github.com/scylladb/scylladb/issues/11475Closes#11106
* github.com:scylladb/scylladb:
version: Increasing version
cql-pytest: Add tests for server-side describe statement
cql-pytest: creating random elements for describe's tests
cql3: Extend CQL grammar with server-side describe statement
cql3:statements: server-side describe statement
data_dictonary: add `get_all_keyspaces()` and `get_user_keyspaces()`
storage_proxy: add `describe_ring()` method
storage_service, locator: extract describe_ring()
data_dictionary:user_types_metadata: add has_type() function
cql3:functions: `get_user_functions()` and `get_user_aggregates()`
implement `keyspace_element` interface
data_dictionary: add `keyspace_element` interface
cql3: single_quote() util function
view: row_lock: lock_ck: reindent
test/topology: enable replace tests
service/raft: report an error when Raft ID can't be found in `raft_group0::remove_from_group0`
service: handle replace correctly with Raft enabled
gms/gossiper: fetch RAFT_SERVER_ID during shadow round
service: storage_service: sleep 2*ring_delay instead of BROADCAST_INTERVAL before replace
Add helper functions to create random elements (keyspaces, tables, types)
to increase the coverage of describe statment's tests.
This commit also adds `random_seed` fixture. The fixture should be
always used when using random functions. In case of test's failure, the
seed will be present in test's signature and the case can be easili
recreated.
After the test finishes, the fixture restores state of `random` to
before-test state.
When we have a table with partition key p and an indexed regular column
v, the test included in this patch checks the query
SELECT p FROM table WHERE v = 1 AND TOKEN(p) > 17
This can work and not require ALLOW FILTERING, because the secondary index
posting-list of "v=1" is ordered in p's token order (to allow SELECT with
and without an index to return the same order - this is explained in
issue #7443). So this test should pass, and indeed it does on both current
Scylla, and Cassandra.
However, it turns out that this was a bug - issue #7043 - in older
versions of Scylla, and only fixed in Scylla 4.6. In older versions,
the SELECT wasn't accepted, claiming it requires ALLOW FILTERING,
and if ALLOW FILTERING was added, the TOKEN(p) > 17 part was silently
ignored.
The fix for issue #7043 actually included regression tests, C++ tests in
test/boost/secondary_index_test.cc. But in this patch we also add a Python
test in test/cql-pytest.
One of the benefits of cql-pytest is that we can (and I did) run the same
test on Cassandra to verify we're not implementing a wrong feature.
Another benefit is that we can run a new test on an old version, and
not even require re-compilation: You can run this new test on any
existing installation of Scylla to check if it still has issue #7043.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closes#12237
The latter is pretty popular test/lib header that disseminates the
former one over whole lot of unit tests. The former, in turn, naturally
includes sstables.hh thus making tons of unrelated tests depend on
sstables class unused by them.
However, simple removal doesn't work, becase of local_shard_only bool
class definition in sstable_utils.hh used in simple_schema.hh. This
thing, in turn, is used in keys making helpers that don't belong to
sstable utils, so these are moved into simple_schema as well.
When done, this affects the mutation_source_test.hh, which needs the
local_shard_only bool class (and helps spreading the sstables.hh
throughout more unrelated tests) and a bunch of .cc test sources that
used sstable_utils.hh to indirectly include various headers of their
demand.
After patching, sstables.hh touches 2x times less tests. As a side
effect the sstables_manager.hh also becomes 2x times less dependent
on by tests.
Continuation of 9bdea110a6
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#12240
trim_clustering_row_ranges_to() is broken for non-full keys in reverse
mode. It will trim the range to
position_in_partition_view::after_key(full_key) instead of
position_in_partition_view::before_key(key), hence it will include the
key in the resulting range rather than exclude it.
Fixes#12180
Refs #1446
A frozen set can be part of the clustering key, and with compact
storage, the corresponding key component can have an empty value.
Comparison was not prepared for this, the iterator attempts to
deserialize the item count and will fail if the value is empty.
Fixes#12242
This pull request introduces support for global secondary indexes based on static columns.
Local secondary indexes based on secondary columns are not planned to be supported and are explicitly forbidden. Because there is only one static row per partition and local indexes require full partition key when querying, such indexes wouldn't be very useful and would only waste resources.
The index table for secondary indexes on static columns, unlike other secondary indexes, do not contain clustering keys from the base table. A static column's value determines a set of full partitions, so the clustering keys would only be unnecessary.
The already existing logic for querying using secondary indexes works after introducing minimal notifications. The view update generation path now works on a common representation of static and clustering rows, but the new representation allowed to keep most of the logic intact.
New cql-pytests are added. All but one of the existing tests for secondary indexes on static columns - ported from Cassandra - now work and have their `xfail` marks lifted; the remaining test requires support for collection indexing, so it will start working only after #2962 is fixed.
Materialized view with static rows as a key are __not__ implemented in this PR.
Fixes: #2963Closes#11166
* github.com:scylladb/scylladb:
test_materialized_view: verify that static columns are not allowed
test_secondary_index: add (currently failing) test for static index paging
test_secondary_index: add more tests for secondary indexes on static columns
cassandra_tests: enable existing tests for static columns
create_index_statement: lift restriction on secondary indexes on static rows
db/view: fetch and process static rows when building indexes
gms/feature_service: introduce SECONDARY_INDEXES_ON_STATIC_COLUMNS cluster feature
create_index_statement: disallow creation of local indexes with static columns
select_statement: prepare paging for indexes on static columns
select_statement: do not attempt to fetch clustering columns from secondary index's table
secondary_index_manager: don't add clustering key columns to index table of static column index
replica/table: adjust the view read-before-write to return static rows when needed
db/view: process static rows in view_update_builder::on_results
db/view: adjust existing view update generation path to use clustering_or_static_row
column_computation: adjust to use clustering_or_static_row
db/view: add clustering_or_static_row
deletable_row: add column_kind parameter to is_live
view_info: adjust view_column to accept column_kind
db/view: base_dependent_view_info: split non-pk columns into regular and static
Adds a test which verifies that static columns are not allowed in
materialized views. Although we added support for static columns in
secondary indexes, which share a lot of code with materialized views,
static columns in materialized views are not yet ready to use.
Currently, when executing queries accelerated by an index on a static
column, paging is unable to break base table partitions across pages and
is forced to return them in whole. This will cause problems if such a
query must return a very large base table partition because it will have
to be loaded into memory.
Fixing this issue will require a more sophisticated approach than what
was done in the PR. For the time being, an xfailing pytest is added
which should start passing after paging is improved.
We need to obtain the Raft ID of the replaced node during the shadow round and
place it in the address map. It won't be placed by the regular gossiping route
if we're replacing using the same IP, because we override the application state
of the replaced node. Even if we replace a node with a different IP, it is not
guaranteed that background gossiping manages update the address map before we
need it, especially in tests where we set ring_delay to 0 and disable
wait_for_gossip_to_settle. The shadow round, on the other hand, performs a
synchronous request (and if it fails during bootstrap, bootstrap will fail -
because we also won't be able to obtain the tokens and Host ID of the replaced
node).
Fetch the Raft ID of the replaced node in `prepare_replacement_info`,
which runs the shadow round. Return it in `replacement_info`. Then
`join_token_ring` passes it to `setup_group0`, which stores it in the
address map. It does that after `join_group0` so the entry is
non-expiring (the replaced node is a member of group 0). Later in the
replace procedure, we call `remove_from_group0` for the replaced node.
`remove_from_group0` will be able to reverse-translate the IP of the
replaced node to its Raft ID using the address map.
Also remove an unconditional 60 seconds sleep from the replace code. Make it
dependent on ring_delay.
Enable the replace tests.
Modify some code related to removing servers from group 0 which depended on
storing IP addresses in the group 0 configuration.
Closes#12172
* github.com:scylladb/scylladb:
test/topology: enable replace tests
service/raft: report an error when Raft ID can't be found in `raft_group0::remove_from_group0`
service: handle replace correctly with Raft enabled
gms/gossiper: fetch RAFT_SERVER_ID during shadow round
service: storage_service: sleep 2*ring_delay instead of BROADCAST_INTERVAL before replace
This change removes sstables.hh from some other headers replacing it
with version.hh and shared_sstable.hh. Also this drops
sstables_manager.hh from some more headers, because this header
propagates sstables.hh via self. That change is pretty straightforward,
but has a recochet in database.hh that needs disk-error-handler.hh.
Without the patch touch sstables/sstable.hh results in 409 targets
recompillation, with the patch -- 299 targets.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closes#12222
There are two similarly named classes: ::test_region_group and
dirty_memory_manager_logalloc::test_region_group. Rename the
former to ::raii_region_group (that's what it's for) and the
latter to ::test_region_group, to reduce confusion.
While deletable_row is used to hold regular columns of a clustering row,
its name or implementation doesn't suggest that it is a requirement. In
fact, some of its methods already take a column_kind parameter which is
used to interpret the kind of columns held in the row.
This commit removes the assumption about the column kind from the
`deletable_row::is_live` method.
This PR hits two goals for "object storage" effort
1. Sstables loader "knows" that sstables components are stored in a Linux directory and uses utils/lister to access it. This is not going to work with sstables over object storage, the loader should be abstracted from the underlying storage.
2. Currently class keyspace and class column_family carry "datadir" and "all_datadirs" on board which are path on local filesystem where sstable files are stored (those usually started with /var/lib/scylla/data). The paths include subsdirs like "snapshots", "staging", etc. This is not going to look nice for obejct storage, the /var/lib/ prefix is excessive and meaningless in this case. Instead, ks and cf should know their "location" and some other component should know the directory where in which the files are stored.
Said that, this PR prepares distributed_loader and sstables_directly to stop using Linux paths explicitly by making both call sstables_manager to list and open sstables object. After it will be possible to teach manager to list sstables from object storage. Also this opens the way to removing paths from keyspace and column_family classes and replacing those with relative "location"s.
Closes#12128
* github.com:scylladb/scylladb:
sstable_directory: Get components lister from manager
sstable_directory: Extract directory lister
sstable_directory: Remove sstable creation callback
sstable_directory: Call manager to make sstables
sstable_directory: Keep error handler generator
sstable_directory: Keep schema_ptr
sstable_directory: Use directory semaphore from manager
sstable_directory: Keep reference on manager
tests: Use sstables creation helper in some cases
sstables_manager: Keep directory semaphore reference
sstables, code: Wrap directory semaphore with concurrency
Currently if a node that is outside of the config tries to add an entry
or modify config transient error is returned and this causes the node
to retry. But the error is not transient. If a node tries to do one of
the operations above it means it was part of the cluster at some point,
but since a node with the same id should not be added back to a cluster
if it is not in the cluster now it will never be.
Return a new error not_a_member to a caller instead.
Message-Id: <Y42mTOx8bNNrHqpd@scylladb.com>
Yet another continuation to previous patch -- IO error handlers
generator is also needed to create sstables.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Continuation of one-before-previous patch. In order to create sstable
without external lambda the directory code needs schema.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
After previous patch sstables_directory code may no longer require for
semaphore argument, because it can get one from manager. This makes the
directory API shorter and simpler.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The sstables_directly accesses /var/lib/scylla/data in two ways -- lists
files in it and opens sstables. The latter is abdtracted with the help
of lambdas passed around, but the former (listing) is done by using
directory liters from utils.
Listing sstables components with directlry lister won't work for object
storage, the directory code will need to call some abstraction layer
instead. Opening sstables with the help of a lambda is a bit of
overkill, having sstables manager at hand could make it much simpler.
Said that, this patch makes sstables_directly reference sstables_manager
on start.
This change will also simplify directory semaphore usage (next patch).
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
