options.hpp

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#pragma once
 
/// @file userver/storages/mysql/options.hpp
 
#include <chrono>
#include <optional>
 
USERVER_NAMESPACE_BEGIN
 
namespace storages::mysql {
 
using TimeoutDuration = std::chrono::milliseconds;
 
/// A structure to control timeouts for MySQL queries
///
/// There is a single parameter, `execute`, which limits the overall time
/// the driver spends executing a query, which includes:
/// * connecting to MySQL server, if there are no connections available and
///   connection pool still has space for new connections;
/// * waiting for a connection to become idle if there are no idle connections
///   and connection pool already has reached its max size;
/// * preparing the statement, if it's absent in statements cache;
/// * executing the statement;
/// * fetching all the statement results, if any, and not in cursor mode.
///
/// In case of a timeout the client gets an exception and the driver drops the
/// connection (no further reuse will take place),
/// otherwise the connection is returned to the pool.
struct CommandControl final {
    /// Overall timeout for a statement being executed.
    TimeoutDuration execute{};
};
 
/// @brief storages::mysql::CommandControl that may not be set.
using OptionalCommandControl = std::optional<CommandControl>;
 
}  // namespace storages::mysql
 
USERVER_NAMESPACE_END