mysql-server/libs/mysql/serialization/serializable.h
2025-03-05 14:31:37 +07:00

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// Copyright (c) 2023, 2024, Oracle and/or its affiliates.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License, version 2.0,
// as published by the Free Software Foundation.
//
// This program is designed to work with certain software (including
// but not limited to OpenSSL) that is licensed under separate terms,
// as designated in a particular file or component or in included license
// documentation. The authors of MySQL hereby grant you an additional
// permission to link the program and your derivative works with the
// separately licensed software that they have either included with
// the program or referenced in the documentation.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License, version 2.0, for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
#ifndef MYSQL_SERIALIZATION_SERIALIZABLE_H
#define MYSQL_SERIALIZATION_SERIALIZABLE_H
#include <tuple>
#include <unordered_set>
#include "mysql/serialization/field_definition.h"
#include "mysql/serialization/field_functor.h"
#include "mysql/serialization/serializable_size_calculator.h"
#include "mysql/serialization/serializable_type_tags.h"
#include "mysql/serialization/serialization_format_version.h"
#include "mysql/serialization/unknown_field_policy.h"
/// @file
/// Experimental API header
/// @addtogroup GroupLibsMysqlSerialization
/// @{
namespace mysql::serialization {
// forward declarations
template <typename Serializer_type, typename... Args>
struct Serializable_size_calculator;
/// @brief Interface for serializable data structures. Classes that implement
/// serializable interface may be serialized automatically by the serializer
/// @note To be implemented by derived:
/// decltype(auto) define_fields { return std::make_tuple(...); } const and
/// non-const version
/// @details Please have a look at examples enclosed in unittest
/// The base class provides:
/// - methods to traverse through fields defined by the user in the
/// Derived_serializable_type
/// - methods to compute a compile-time upper bound on the size of message
/// defined by the user in Derived_serializable_type
/// - methods to compute the exact size of a particular message at runtime,
/// taking into account the current values of fields defined by the user
/// in the Derived_serializable_type
/// Derived class should provide:
/// - decltype(auto) define_fields { return std::make_tuple(...); } const
/// defines fields to be encoded. To define fields,
/// helpers defined in the "field_definition_helpers.h" shall be used.
/// Sufficient information about the field is the field reference. The
/// message designer can also define:
/// - fixed size of an integer / upper bound of the string length
/// - encode predicate, which will be called by the encoding functions
/// to determine whether field should be encoded
/// - an unknown_field_policy, defined by the encoder and applied by the
/// decoder in case decoder does not recognize a field
/// - decltype(auto) define_fields { return std::make_tuple(...); }
/// defines fields to be decoded. To define fields,
/// helpers defined in the "field_definition_helpers.h" shall be used.
/// Sufficient information about the field is the field reference. The
/// message designer can also define:
/// - fixed size of an integer / upper bound of the string length
/// - field missing functor, which will be called by the decoding functions
/// in case field is not encoded in the message
/// - an unknown_field_policy, defined by the encoder and applied by the
/// decoder in case decoder does not recognize a field
template <class Derived_serializable_type>
class Serializable {
public:
/// @brief calls functor for each field
/// @tparam Serializable_functor_type Type of functor to be applied on the
/// serializable
/// @tparam Field_functor_type Type of functor to be applied on the field
/// @param func_s Functor to be called for each serializable field
/// @param func_f Functor to be called for each non-serializable field
template <class Serializable_functor_type, class Field_functor_type>
void do_for_each_field(Serializable_functor_type &&func_s,
Field_functor_type &&func_f);
/// @brief calls functor for each field, const version
/// @tparam Serializable_functor_type Type of functor to be applied on the
/// serializable
/// @tparam Field_functor_type Type of functor to be applied on the field
/// @param func_s Functor to be called for each serializable field
/// @param func_f Functor to be called for each non-serializable field
template <class Serializable_functor_type, class Field_functor_type>
void do_for_each_field(Serializable_functor_type &&func_s,
Field_functor_type &&func_f) const;
// available for serializer derived
/// @brief This function calculates last field id of this type
/// @return last field id
static constexpr Field_id_type get_last_field_id() {
using Tuple_type_captured =
decltype(std::declval<Derived_serializable_type>().define_fields());
return std::tuple_size_v<Tuple_type_captured> - 1;
}
/// @brief Returns serializable object fields size, internal function
/// (without serializable metadata size)
/// @tparam Serializer_type Type of serializer used to format fields
/// overhead added by serializer, including overhead of nested types
/// @returns Serializable internal size
template <typename Serializer_type>
std::size_t get_size_internal() const;
/// @brief Performs iteration over all of the serializable fields and checks
/// whether any of the fields in this serializable is provided
/// @return True in case any of the fields in all levels, starting from this
/// one, is provided
bool is_any_field_provided() const;
/// @brief Returns serializable object fields maximum size, internal function
/// (without serializable metadata size)
/// @tparam Serializer_type Type of serializer used to format fields
/// object will have this maximum size
/// @return This class maximum declared size
template <typename Serializer_type>
static constexpr std::size_t get_max_size_internal() {
using Tuple_type_captured =
decltype(std::declval<Derived_serializable_type>().define_fields());
return Serializable_size_calculator<Serializer_type,
Tuple_type_captured>::get_max_size();
}
/// @brief Sets unknown field policy for this object
/// @param policy Chosen policy, determines what decoder should do in case it
/// encounters this object in the stream but this object definition is
/// unknown to the decoder
void set_unknown_field_policy(const Unknown_field_policy &policy) {
m_unknown_field_policy = policy;
}
bool is_ignorable() const {
return m_unknown_field_policy == Unknown_field_policy::ignore;
}
protected:
using Tag = Serializable_tag;
template <class Serializer_derived_type, class Archive_type>
friend class Serializer;
template <class Derived_serializable_type_current>
friend class Serializable;
/// @brief do_for_each_field helper
template <class Serializable_functor_type, class Field_functor_type,
class Tuple_type, std::size_t... Is>
void do_for_each_field(Serializable_functor_type &&func_s,
Field_functor_type &&func_f, Tuple_type &&tuple,
std::index_sequence<Is...>);
/// @brief do_for_each_field helper
template <class Serializable_functor_type, class Field_functor_type,
class Field_type>
void do_for_one_field(Serializable_functor_type &&func_s,
Field_functor_type &&func_f, Field_type &field,
std::size_t field_id);
/// @brief do_for_each_field helper
template <class Serializable_functor_type, class Field_functor_type,
class Field_type>
void do_for_one_field(Serializable_functor_type &&func_s,
Field_functor_type &&func_f, Field_type &field,
std::size_t field_id, Serializable_tag);
/// @brief do_for_each_field helper
template <class Serializable_functor_type, class Field_functor_type,
class Field_type>
void do_for_one_field(Serializable_functor_type &&,
Field_functor_type &&func_f, Field_type &field,
std::size_t field_id, Field_definition_tag);
/// @brief do_for_each_field (const) helper
template <class Serializable_functor_type, class Field_functor_type,
class Tuple_type, std::size_t... Is>
void do_for_each_field(Serializable_functor_type &&func_s,
Field_functor_type &&func_f, Tuple_type &&tuple,
std::index_sequence<Is...>) const;
/// @brief do_for_each_field (const) helper
template <class Serializable_functor_type, class Field_functor_type,
class Field_type>
void do_for_one_field(Serializable_functor_type &&func_s,
Field_functor_type &&func_f, const Field_type &field,
std::size_t field_id) const;
/// @brief do_for_each_field (const) helper
template <class Serializable_functor_type, class Field_functor_type,
class Field_type>
void do_for_one_field(Serializable_functor_type &&func_s,
Field_functor_type &&func_f, const Field_type &field,
std::size_t field_id, Serializable_tag) const;
/// @brief do_for_each_field (const) helper
template <class Serializable_functor_type, class Field_functor_type,
class Field_type>
void do_for_one_field(Serializable_functor_type &&,
Field_functor_type &&func_f, const Field_type &field,
std::size_t field_id, Field_definition_tag) const;
// copy-move semantics
Serializable() = default;
Serializable(const Serializable &) = default;
Serializable(Serializable &&) = default;
Serializable &operator=(const Serializable &) = default;
Serializable &operator=(Serializable &&) = default;
/// @brief Creation of Serializable objects is prohibited
virtual ~Serializable() = default;
private:
/// Unknown field policy for this serializable object
Unknown_field_policy m_unknown_field_policy = Unknown_field_policy::ignore;
};
} // namespace mysql::serialization
/// @}
#include "mysql/serialization/serializable_impl.hpp"
#endif // MYSQL_SERIALIZATION_SERIALIZABLE_H