// Copyright 2014 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef COMPONENTS_VALUE_STORE_VALUE_STORE_FRONTEND_H_ #define COMPONENTS_VALUE_STORE_VALUE_STORE_FRONTEND_H_ #include #include #include "base/callback.h" #include "base/memory/ref_counted.h" #include "base/values.h" namespace base { class FilePath; class SequencedTaskRunner; } // namespace base namespace value_store { class ValueStoreFactory; // A frontend for a LeveldbValueStore, for use on the UI thread. class ValueStoreFrontend { public: using ReadCallback = base::OnceCallback)>; ValueStoreFrontend( const scoped_refptr& store_factory, const base::FilePath& directory, const std::string& uma_client_name, const scoped_refptr& origin_task_runner, const scoped_refptr& file_task_runner); ~ValueStoreFrontend(); ValueStoreFrontend(const ValueStoreFrontend&) = delete; ValueStoreFrontend& operator=(const ValueStoreFrontend&) = delete; // Retrieves a value from the database asynchronously, passing a copy to // |callback| when ready. NULL is passed if no matching entry is found. void Get(const std::string& key, ReadCallback callback); // Sets a value with the given key. void Set(const std::string& key, std::unique_ptr value); // Removes the value with the given key. void Remove(const std::string& key); private: class Backend; // A helper class to manage lifetime of the backing ValueStore, which lives // on the FILE thread. scoped_refptr backend_; // The task runner on which to fire callbacks. scoped_refptr origin_task_runner_; scoped_refptr file_task_runner_; }; } // namespace value_store #endif // COMPONENTS_VALUE_STORE_VALUE_STORE_FRONTEND_H_