| // Copyright 2014 The Chromium Authors |
| // 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 <optional> |
| #include <string> |
| |
| #include "base/functional/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<void(std::optional<base::Value>)>; |
| |
| ValueStoreFrontend( |
| const scoped_refptr<ValueStoreFactory>& store_factory, |
| const base::FilePath& directory, |
| const std::string& uma_client_name, |
| const scoped_refptr<base::SequencedTaskRunner>& origin_task_runner, |
| const scoped_refptr<base::SequencedTaskRunner>& 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, base::Value 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> backend_; |
| |
| // The task runner on which to fire callbacks. |
| scoped_refptr<base::SequencedTaskRunner> origin_task_runner_; |
| |
| scoped_refptr<base::SequencedTaskRunner> file_task_runner_; |
| }; |
| |
| } // namespace value_store |
| |
| #endif // COMPONENTS_VALUE_STORE_VALUE_STORE_FRONTEND_H_ |
