Files
scylladb/data_dictionary/data_dictionary.hh
Kefu Chai 168ade72f8 treewide: replace formatter<std::string_view> with formatter<string_view>
in in {fmt} before v10, it provides the specialization of `fmt::formatter<..>`
for `std::string_view` as well as the specialization of `fmt::formatter<..>`
for `fmt::string_view` which is an implementation builtin in {fmt} for
compatibility of pre-C++17. and this type is used even if the code is
compiled with C++ stadandard greater or equal to C++17. also, before v10,
the `fmt::formatter<std::string_view>::format()` is defined so it accepts
`std::string_view`. after v10, `fmt::formatter<std::string_view>` still
exists, but it is now defined using `format_as()` machinery, so it's
`format()` method does not actually accept `std::string_view`, it
accepts `fmt::string_view`, as the former can be converted to
`fmt::string_view`.

this is why we can inherit from `fmt::formatter<std::string_view>` and
use `formatter<std::string_view>::format(foo, ctx);` to implement the
`format()` method with {fmt} v9, but we cannot do this with {fmt} v10,
and we would have following compilation failure:

```
FAILED: service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o
/home/kefu/.local/bin/clang++ -DFMT_DEPRECATED_OSTREAM -DFMT_SHARED -DSCYLLA_BUILD_MODE=release -DSEASTAR_API_LEVEL=7 -DSEASTAR_LOGGER_COMPILE_TIME_FMT -DSEASTAR_LOGGER_TYPE_STDOUT -DSEASTAR_SCHEDULING_GROUPS_COUNT=16 -DSEASTAR_SSTRING -DXXH_PRIVATE_API -DCMAKE_INTDIR=\"RelWithDebInfo\" -I/home/kefu/dev/scylladb -I/home/kefu/dev/scylladb/build/gen -I/home/kefu/dev/scylladb/seastar/include -I/home/kefu/dev/scylladb/build/seastar/gen/include -I/home/kefu/dev/scylladb/build/seastar/gen/src -ffunction-sections -fdata-sections -O3 -g -gz -std=gnu++20 -fvisibility=hidden -Wall -Werror -Wextra -Wno-error=deprecated-declarations -Wimplicit-fallthrough -Wno-c++11-narrowing -Wno-deprecated-copy -Wno-mismatched-tags -Wno-missing-field-initializers -Wno-overloaded-virtual -Wno-unsupported-friend -Wno-enum-constexpr-conversion -Wno-unused-parameter -ffile-prefix-map=/home/kefu/dev/scylladb=. -march=westmere -mllvm -inline-threshold=2500 -fno-slp-vectorize -U_FORTIFY_SOURCE -Werror=unused-result -MD -MT service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o -MF service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o.d -o service/CMakeFiles/service.dir/RelWithDebInfo/topology_state_machine.cc.o -c /home/kefu/dev/scylladb/service/topology_state_machine.cc
/home/kefu/dev/scylladb/service/topology_state_machine.cc:254:41: error: no matching member function for call to 'format'
  254 |     return formatter<std::string_view>::format(it->second, ctx);
      |            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
/usr/include/fmt/core.h:2759:22: note: candidate function template not viable: no known conversion from 'seastar::basic_sstring<char, unsigned int, 15>' to 'const fmt::basic_string_view<char>' for 1st argument
 2759 |   FMT_CONSTEXPR auto format(const T& val, FormatContext& ctx) const
      |                      ^      ~~~~~~~~~~~~
```

because the inherited `format()` method actually comes from
`fmt::formatter<fmt::string_view>`. to reduce the confusion, in this
change, we just inherit from `fmt::format<string_view>`, where
`string_view` is actually `fmt::string_view`. this follows
the document at
https://fmt.dev/latest/api.html#formatting-user-defined-types,
and since there is less indirection under the hood -- we do not
use the specialization created by `FMT_FORMAT_AS` which inherit
from `formatter<fmt::string_view>`, hopefully this can improve
the compilation speed a little bit. also, this change addresses
the build failure with {fmt} v10.

Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>

Closes scylladb/scylladb#18299
2024-04-19 07:44:07 +03:00

148 lines
4.8 KiB
C++

/*
* Copyright (C) 2021-present ScyllaDB
*/
/*
* SPDX-License-Identifier: AGPL-3.0-or-later
*/
#pragma once
#include <optional>
#include <set>
#include <string_view>
#include <vector>
#include <seastar/core/shared_ptr.hh>
#include "seastarx.hh"
#include "schema/schema_fwd.hh"
namespace replica {
class database; // For transition; remove
}
class schema;
using schema_ptr = lw_shared_ptr<const schema>;
class view_ptr;
namespace db {
class config;
class extensions;
}
namespace secondary_index {
class secondary_index_manager;
}
namespace gms {
class feature_service;
}
namespace locator {
class abstract_replication_strategy;
}
// Classes representing the overall schema, but without access to data.
// Useful on the coordinator side (where access to data is via storage_proxy).
//
// Everything here is type-erased to reduce dependencies. No references are
// kept, so lower-level objects like keyspaces and tables must not be held
// across continuations.
namespace data_dictionary {
// Used to forward all operations to the underlying backing store.
class impl;
class user_types_metadata;
class keyspace_metadata;
class no_such_keyspace : public std::runtime_error {
public:
no_such_keyspace(std::string_view ks_name);
};
class no_such_column_family : public std::runtime_error {
public:
no_such_column_family(const table_id& uuid);
no_such_column_family(std::string_view ks_name, std::string_view cf_name);
no_such_column_family(std::string_view ks_name, const table_id& uuid);
};
class table {
const impl* _ops;
const void* _table;
private:
friend class impl;
table(const impl* ops, const void* table);
public:
schema_ptr schema() const;
const std::vector<view_ptr>& views() const;
const secondary_index::secondary_index_manager& get_index_manager() const;
};
class keyspace {
const impl* _ops;
const void* _keyspace;
private:
friend class impl;
keyspace(const impl* ops, const void* keyspace);
public:
bool is_internal() const;
lw_shared_ptr<keyspace_metadata> metadata() const;
const user_types_metadata& user_types() const;
const locator::abstract_replication_strategy& get_replication_strategy() const;
};
class database {
const impl* _ops;
const void* _database;
private:
friend class impl;
database(const impl* ops, const void* database);
public:
const table_schema_version& get_version() const;
keyspace find_keyspace(std::string_view name) const;
std::optional<keyspace> try_find_keyspace(std::string_view name) const;
bool has_keyspace(std::string_view name) const; // throws no_keyspace
std::vector<keyspace> get_keyspaces() const;
std::vector<sstring> get_user_keyspaces() const;
std::vector<sstring> get_all_keyspaces() const;
std::vector<table> get_tables() const;
table find_table(std::string_view ks, std::string_view table) const; // throws no_such_column_family
table find_column_family(table_id uuid) const; // throws no_such_column_family
schema_ptr find_schema(std::string_view ks, std::string_view table) const; // throws no_such_column_family
schema_ptr find_schema(table_id uuid) const; // throws no_such_column_family
table find_column_family(schema_ptr s) const;
bool has_schema(std::string_view ks_name, std::string_view cf_name) const;
std::optional<table> try_find_table(std::string_view ks, std::string_view table) const;
std::optional<table> try_find_table(table_id id) const;
const db::config& get_config() const;
std::set<sstring> existing_index_names(std::string_view ks_name, std::string_view cf_to_exclude = sstring()) const;
schema_ptr find_indexed_table(std::string_view ks_name, std::string_view index_name) const;
sstring get_available_index_name(std::string_view ks_name, std::string_view table_name,
std::optional<sstring> index_name_root) const;
schema_ptr get_cdc_base_table(sstring_view ks_name, std::string_view table_name) const;
schema_ptr get_cdc_base_table(const schema&) const;
const db::extensions& extensions() const;
const gms::feature_service& features() const;
replica::database& real_database() const; // For transition; remove
};
}
#if FMT_VERSION < 100000
// fmt v10 introduced formatter for std::exception
template <>
struct fmt::formatter<data_dictionary::no_such_keyspace> : fmt::formatter<string_view> {
auto format(const data_dictionary::no_such_keyspace& e, fmt::format_context& ctx) const {
return fmt::format_to(ctx.out(), "{}", e.what());
}
};
template <>
struct fmt::formatter<data_dictionary::no_such_column_family> : fmt::formatter<string_view> {
auto format(const data_dictionary::no_such_column_family& e, fmt::format_context& ctx) const {
return fmt::format_to(ctx.out(), "{}", e.what());
}
};
#endif