ClickHouse/src/Access/MemoryAccessStorage.h

69 lines
2.8 KiB
C++

#pragma once
#include <Access/IAccessStorage.h>
#include <base/defines.h>
#include <list>
#include <memory>
#include <mutex>
#include <unordered_map>
namespace DB
{
class AccessChangesNotifier;
/// Implementation of IAccessStorage which keeps all data in memory.
class MemoryAccessStorage : public IAccessStorage
{
public:
static constexpr char STORAGE_TYPE[] = "memory";
explicit MemoryAccessStorage(const String & storage_name_, AccessChangesNotifier & changes_notifier_, bool allow_backup_);
const char * getStorageType() const override { return STORAGE_TYPE; }
/// Inserts an entity with a specified ID.
/// If `replace_if_exists == true` it can replace an existing entry with such ID and also remove an existing entry
/// with such name & type.
bool insertWithID(const UUID & id, const AccessEntityPtr & new_entity, bool replace_if_exists, bool throw_if_exists);
/// Removes all entities except a specified list.
void removeAllExcept(const std::vector<UUID> & ids_to_keep);
/// Sets all entities at once.
void setAll(const std::vector<AccessEntityPtr> & all_entities);
void setAll(const std::vector<std::pair<UUID, AccessEntityPtr>> & all_entities);
bool exists(const UUID & id) const override;
bool isBackupAllowed() const override { return backup_allowed; }
void restoreFromBackup(RestorerFromBackup & restorer) override;
private:
std::optional<UUID> findImpl(AccessEntityType type, const String & name) const override;
std::vector<UUID> findAllImpl(AccessEntityType type) const override;
AccessEntityPtr readImpl(const UUID & id, bool throw_if_not_exists) const override;
std::optional<UUID> insertImpl(const AccessEntityPtr & entity, bool replace_if_exists, bool throw_if_exists) override;
bool removeImpl(const UUID & id, bool throw_if_not_exists) override;
bool updateImpl(const UUID & id, const UpdateFunc & update_func, bool throw_if_not_exists) override;
bool insertNoLock(const UUID & id, const AccessEntityPtr & entity, bool replace_if_exists, bool throw_if_exists) TSA_REQUIRES(mutex);
bool removeNoLock(const UUID & id, bool throw_if_not_exists) TSA_REQUIRES(mutex);
bool updateNoLock(const UUID & id, const UpdateFunc & update_func, bool throw_if_not_exists) TSA_REQUIRES(mutex);
void removeAllExceptNoLock(const std::vector<UUID> & ids_to_keep) TSA_REQUIRES(mutex);
struct Entry
{
UUID id;
AccessEntityPtr entity;
};
mutable std::mutex mutex;
std::unordered_map<UUID, Entry> entries_by_id TSA_GUARDED_BY(mutex); /// We want to search entries both by ID and by the pair of name and type.
std::unordered_map<String, Entry *> entries_by_name_and_type[static_cast<size_t>(AccessEntityType::MAX)] TSA_GUARDED_BY(mutex);
AccessChangesNotifier & changes_notifier;
const bool backup_allowed = false;
};
}