builder.hpp

#pragma once
 
#include <ydb-cpp-sdk/client/params/params.h>
 
#include <string>
#include <type_traits>
#include <utility>
 
#include <userver/ydb/impl/cast.hpp>
#include <userver/ydb/io/traits.hpp>
 
USERVER_NAMESPACE_BEGIN
 
namespace ydb {
 
class TableClient;
class Transaction;
 
class PreparedArgsBuilder final {
 public:
  PreparedArgsBuilder(PreparedArgsBuilder&&) noexcept = default;
  PreparedArgsBuilder& operator=(PreparedArgsBuilder&&) = delete;
 
  /// Supported types and required includes are documented in:
  /// <userver/ydb/io/supported_types.hpp>
  template <typename T>
  void Add(const std::string& name, T&& value);
 
  /// @cond
  // For internal use only.
  explicit PreparedArgsBuilder(NYdb::TParamsBuilder&& builder)
      : builder_(std::move(builder)) {}
 
  // For internal use only.
  template <typename... NamesValues>
  void AddParams(NamesValues&&... names_values);
  /// @endcond
 
 private:
  friend class Transaction;
  friend class TableClient;
  struct PreparedArgsWithKey;
 
  NYdb::TParams Build() && { return std::move(builder_).Build(); }
 
  PreparedArgsWithKey operator<<(const std::string& key);
 
  NYdb::TParamsBuilder builder_;
};
 
template <typename T>
void PreparedArgsBuilder::Add(const std::string& name, T&& value) {
  auto& param_builder = builder_.AddParam(impl::ToString(name));
  Write(param_builder, std::forward<T>(value));
  param_builder.Build();
}
 
template <typename... NamesValues>
void PreparedArgsBuilder::AddParams(NamesValues&&... names_values) {
  [[maybe_unused]] decltype(auto) result =
      (*this << ... << std::forward<NamesValues>(names_values));
  static_assert(std::is_same_v<decltype(result), PreparedArgsBuilder&>);
}
 
struct PreparedArgsBuilder::PreparedArgsWithKey final {
  PreparedArgsBuilder& builder;
  const std::string& key;
 
  template <typename T>
  PreparedArgsBuilder& operator<<(T&& value) const {
    builder.Add(key, std::forward<T>(value));
    return builder;
  }
};
 
inline auto PreparedArgsBuilder::operator<<(const std::string& key)
    -> PreparedArgsWithKey {
  return PreparedArgsWithKey{*this, key};
}
 
}  // namespace ydb
 
USERVER_NAMESPACE_END