After changing the prepare_ methods of migration_manager to
functions, the migration_manager& parameter of
schema_altering_statement::prepare_schema_mutations has been
unused by all classes inheriting from schema_altering_statement.
The migration_manager service is responsible for schema convergence
in the cluster - pushing schema changes to other nodes and pulling
schema when a version mismatch is observed. However, there is also
a part of migration_manager that doesn't really belong there -
creating mutations for schema updates. These are the functions with
prepare_ prefix. They don't modify any state and don't exchange any
messages. They only need to read the local database.
We take these functions out of migration_manager and make them
separate functions to reduce the dependency of other modules
(especially query_processor and CQL statements) on
migration_manager. Since all of these functions only need access
to storage_proxy (or even only replica::database), doing such a
refactor is not complicated. We just have to add one parameter,
either storage_proxy or database and both of them are easily
accessible in the places where these functions are called.
We want to stop relying on `qp.get_migration_manager()`, so we can make
the function private in the future. This in turn is a prerequisite for
splitting `query_processor` initialization into two phases, where the
first phase will only allow local queries (and won't require
`migration_manager`).
Validation of a CREATE MATERIALIZED VIEW statement takes place inside
the prepare_schema_mutations() method.
I would like to generate warnings during this validation, but there's
currently no way to pass them.
Let's add one more return value - a vector of CQL warnings generated
during the execution of this statement.
A new alias is added to make it clear what the function is returning:
```c++
// A vector of CQL warnings generated during execution of a statement.
using cql_warnings_vec = std::vector<sstring>;
```
Later the warnings will be sent to the user by the function
schema_altering_statment::execute(), which is the only caller
of prepare_schema_mutations().
Signed-off-by: Jan Ciolek <jan.ciolek@scylladb.com>
After we move the compilation to a alien thread, the completion
of the compilation will be signaled by fulfilling a seastar promise.
As a result, the `precompile` function will return a future, and
because of that, other functions that use the `precompile` functions
will also become futures.
We can do all the neccessary adjustments beforehand, so that the actual
patch that moves the compilation will contain less irrelevant changes.
Move mutation-related files to a new mutation/ directory. The names
are kept in the global namespace to reduce churn; the names are
unambiguous in any case.
mutation_reader remains in the readers/ module.
mutation_partition_v2.cc was missing from CMakeLists.txt; it's added in this
patch.
This is a step forward towards librarization or modularization of the
source base.
Closes#12788
The functions which prepare schema change mutations (such as
`prepare_new_column_family_announcement`) would use internally
generated timestamps for these mutations. When schema changes are
managed by group 0 we want to ensure that timestamps of mutations
applied through Raft are monotonic. We will generate these timestamps at
call sites and pass them into the `prepare_` functions. This commit
prepares the APIs.
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
The schema_altering_statement declares this pure virtual method. This
patch changes its first argument from proxy into query processor and
fixes what compiler errors about.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Stop using database (and including database.hh) for schema related
purposes and use data_dictionary instead.
data_dictionary::database::real_database() is called from several
places, for these reasons:
- calling yet-to-be-converted code
- callers with a legitimate need to access data (e.g. system_keyspace)
but with the ::database accessor removed from query_processor.
We'll need to find another way to supply system_keyspace with
data access.
- to gain access to the wasm engine for testing whether used
defined functions compile. We'll have to find another way to
do this as well.
The change is a straightforward replacement. One case in
modification_statement had to change a capture, but everything else
was just a search-and-replace.
Some files that lost "database.hh" gained "mutation.hh", which they
previously had access to through "database.hh".
To be able to confine raft to the execution time of a statement we need to
move all schema access to the execution time as well. Since the
validation code access the schema lets run it during execution.
