dist_lock_strategy.hpp

Go to the documentation of this file.

#pragma once
 
/// @file userver/storages/postgres/dist_lock_strategy.hpp
/// @brief @copybrief storages::postgres::DistLockStrategy
 
#include <string_view>
 
#include <userver/dist_lock/dist_lock_settings.hpp>
#include <userver/dist_lock/dist_lock_strategy.hpp>
#include <userver/engine/deadline.hpp>
#include <userver/rcu/rcu.hpp>
#include <userver/storages/postgres/options.hpp>
#include <userver/storages/postgres/query.hpp>
 
USERVER_NAMESPACE_BEGIN
 
namespace storages::postgres {
 
/// Postgres distributed locking strategy
class DistLockStrategy final : public dist_lock::DistLockStrategyBase {
public:
    DistLockStrategy(
        ClusterPtr cluster,
        std::string_view table,
        std::string_view lock_name,
        const dist_lock::DistLockSettings& settings
    );
 
    void Acquire(std::chrono::milliseconds lock_ttl, const std::string& locker_id) override;
 
    void Prolong(std::chrono::milliseconds lock_ttl, const std::string& locker_id) override;
 
    void Release(const std::string& locker_id) override;
 
    void UpdateCommandControl(CommandControl cc);
 
private:
    void RunLockQuery(const Query& query, std::chrono::milliseconds lock_ttl, std::string_view locker_id);
 
    ClusterPtr cluster_;
    rcu::Variable<CommandControl> cc_;
    const Query acquire_query_;
    const Query prolong_query_;
    const Query release_query_;
    const std::string lock_name_;
    const std::string owner_prefix_;
};
 
}  // namespace storages::postgres
 
USERVER_NAMESPACE_END