portal.hpp

#pragma once
 
#include <memory>
#include <string>
 
#include <userver/engine/deadline.hpp>
 
#include <userver/storages/postgres/detail/connection_ptr.hpp>
#include <userver/storages/postgres/detail/query_parameters.hpp>
#include <userver/storages/postgres/options.hpp>
#include <userver/storages/postgres/postgres_fwd.hpp>
#include <userver/storages/postgres/query.hpp>
#include <userver/storages/postgres/result_set.hpp>
 
#include <userver/utils/fast_pimpl.hpp>
#include <userver/utils/strong_typedef.hpp>
 
USERVER_NAMESPACE_BEGIN
 
namespace storages::postgres {
 
using PortalName = USERVER_NAMESPACE::utils::StrongTypedef<struct PortalNameTag, std::string>;
 
class Portal {
public:
    Portal(
        detail::Connection* conn,
        const Query& query,
        const detail::QueryParameters& = {},
        OptionalCommandControl cmd_ctl = {}
    );
    Portal(
        detail::Connection* conn,
        const PortalName&,
        const Query& query,
        const detail::QueryParameters& = {},
        OptionalCommandControl cmd_ctl = {}
    );
 
    Portal(Portal&&) noexcept;
    Portal& operator=(Portal&&) noexcept;
 
    Portal(const Portal&) = delete;
    Portal& operator=(const Portal&) = delete;
 
    ~Portal();
 
    ResultSet Fetch(std::uint32_t n_rows);
 
    bool Done() const;
    std::size_t FetchedSoFar() const;
 
    explicit operator bool() const { return !Done(); }
 
    /// Returns true if CMake option USERVER_FEATURE_PATCH_LIBPQ was set to ON
    /// and PostgreSQL portals could be created.
    static bool IsSupportedByDriver() noexcept;
 
private:
    static constexpr std::size_t kImplSize = 96;
    static constexpr std::size_t kImplAlign = 8;
 
    struct Impl;
    USERVER_NAMESPACE::utils::FastPimpl<Impl, kImplSize, kImplAlign> pimpl_;
};
 
}  // namespace storages::postgres
 
USERVER_NAMESPACE_END