ClickHouse/dbms/src/Access/MultipleAccessStorage.h

54 lines
2.1 KiB
C++

#pragma once
#include <Access/IAccessStorage.h>
#include <Common/LRUCache.h>
#include <mutex>
namespace DB
{
/// Implementation of IAccessStorage which contains multiple nested storages.
class MultipleAccessStorage : public IAccessStorage
{
public:
using Storage = IAccessStorage;
MultipleAccessStorage(std::vector<std::unique_ptr<Storage>> nested_storages_, size_t index_of_nested_storage_for_insertion_ = 0);
~MultipleAccessStorage() override;
std::vector<UUID> findMultiple(std::type_index type, const String & name) const;
template <typename EntityType>
std::vector<UUID> findMultiple(const String & name) const { return findMultiple(EntityType::TYPE, name); }
const Storage * findStorage(const UUID & id) const;
Storage * findStorage(const UUID & id);
const Storage & getStorage(const UUID & id) const;
Storage & getStorage(const UUID & id);
Storage & getStorageByIndex(size_t i) { return *(nested_storages[i]); }
const Storage & getStorageByIndex(size_t i) const { return *(nested_storages[i]); }
protected:
std::optional<UUID> findImpl(std::type_index type, const String & name) const override;
std::vector<UUID> findAllImpl(std::type_index type) const override;
bool existsImpl(const UUID & id) const override;
AccessEntityPtr readImpl(const UUID & id) const override;
String readNameImpl(const UUID &id) const override;
UUID insertImpl(const AccessEntityPtr & entity, bool replace_if_exists) override;
void removeImpl(const UUID & id) override;
void updateImpl(const UUID & id, const UpdateFunc & update_func) override;
SubscriptionPtr subscribeForChangesImpl(const UUID & id, const OnChangedHandler & handler) const override;
SubscriptionPtr subscribeForChangesImpl(std::type_index type, const OnChangedHandler & handler) const override;
bool hasSubscriptionImpl(const UUID & id) const override;
bool hasSubscriptionImpl(std::type_index type) const override;
private:
std::vector<std::unique_ptr<Storage>> nested_storages;
IAccessStorage * nested_storage_for_insertion;
mutable LRUCache<UUID, Storage *> ids_cache;
mutable std::mutex ids_cache_mutex;
};
}