SavedFilesService interface in //extensions

extensions/browser/api/file_system/saved_files_service.h

-// Copyright 2013 The Chromium Authors. All rights reserved.
+// Copyright 2017 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 APPS_SAVED_FILES_SERVICE_H_
-#define APPS_SAVED_FILES_SERVICE_H_
+#ifndef EXTENSIONS_BROWSER_API_FILE_SYSTEM_SAVED_FILES_SERVICE_H_
+#define EXTENSIONS_BROWSER_API_FILE_SYSTEM_SAVED_FILES_SERVICE_H_
 
-#include <map>
-#include <memory>
-#include <set>
 #include <string>
-#include <vector>
 
 #include "base/files/file_path.h"
-#include "base/gtest_prod_util.h"
-#include "components/keyed_service/core/keyed_service.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
-
-namespace content {
-class BrowserContext;
-}
-
-class SavedFilesServiceUnitTest;
-FORWARD_DECLARE_TEST(SavedFilesServiceUnitTest, RetainTwoFilesTest);
-FORWARD_DECLARE_TEST(SavedFilesServiceUnitTest, EvictionTest);
-FORWARD_DECLARE_TEST(SavedFilesServiceUnitTest, SequenceNumberCompactionTest);
 
 namespace extensions {
-class Extension;
-}
 
-namespace apps {
+// Provides an LRU of saved file entries that persist across app reloads.
+class SavedFilesService {
+ public:
+  // Represents a file entry that a user has given an app permission to
+  // access. Must be serializable for persisting to disk.
+  struct Entry {
+    Entry();
 
-// Represents a file entry that a user has given an app permission to
-// access. Will be persisted to disk (in the Preferences file), so should remain
-// serializable.
-struct SavedFileEntry {
-  SavedFileEntry();
+    Entry(const std::string& id,
+          const base::FilePath& path,
+          bool is_directory,
+          int sequence_number);
 
-  SavedFileEntry(const std::string& id,
-                 const base::FilePath& path,
-                 bool is_directory,
-                 int sequence_number);
+    // The opaque id of this file entry.
+    std::string id;
 
-  // The opaque id of this file entry.
-  std::string id;
+    // The path to a file entry that the app had permission to access.
+    base::FilePath path;
 
-  // The path to a file entry that the app had permission to access.
-  base::FilePath path;
+    // Whether or not the entry refers to a directory.
+    bool is_directory;
 
-  // Whether or not the entry refers to a directory.
-  bool is_directory;
+    // The sequence number in the LRU of the file entry. The value 0 indicates
+    // that the entry is not in the LRU.
+    int sequence_number;
+  };
 
-  // The sequence number in the LRU of the file entry. The value 0 indicates
-  // that the entry is not in the LRU.
-  int sequence_number;
-};
-
-// Tracks the files that apps have retained access to both while running and
-// when suspended.
-class SavedFilesService : public KeyedService,
-                          public content::NotificationObserver {
- public:
-  explicit SavedFilesService(content::BrowserContext* context);
-  ~SavedFilesService() override;
-
-  static SavedFilesService* Get(content::BrowserContext* context);
+  virtual ~SavedFilesService() {}
 
   // Registers a file entry with the saved files service, making it eligible to
   // be put into the queue. File entries that are in the retained files queue at
   // object construction are automatically registered.
-  void RegisterFileEntry(const std::string& extension_id,
-                         const std::string& id,
-                         const base::FilePath& file_path,
-                         bool is_directory);
+  virtual void RegisterFileEntry(const std::string& extension_id,
+                                 const std::string& id,
+                                 const base::FilePath& file_path,
+                                 bool is_directory) = 0;
 
   // If the file with |id| is not in the queue of files to be retained
   // permanently, adds the file to the back of the queue, evicting the least
   // recently used entry at the front of the queue if it is full. If it is
   // already present, moves it to the back of the queue. The |id| must have been
   // registered.
-  void EnqueueFileEntry(const std::string& extension_id, const std::string& id);
+  virtual void EnqueueFileEntry(const std::string& extension_id,
+                                const std::string& id) = 0;
 
   // Returns whether the file entry with the given |id| has been registered.
-  bool IsRegistered(const std::string& extension_id, const std::string& id);
+  virtual bool IsRegistered(const std::string& extension_id,
+                            const std::string& id) = 0;
 
   // Gets a borrowed pointer to the file entry with the specified |id|. Returns
-  // NULL if the file entry has not been registered.
-  const SavedFileEntry* GetFileEntry(const std::string& extension_id,
-                                     const std::string& id);
-
-  // Returns all registered file entries.
-  std::vector<SavedFileEntry> GetAllFileEntries(
-      const std::string& extension_id);
-
-  // Clears all retained files if the app does not have the
-  // fileSystem.retainEntries permission.
-  void ClearQueueIfNoRetainPermission(const extensions::Extension* extension);
-
-  // Clears all retained files.
-  void ClearQueue(const extensions::Extension* extension);
-
-  // Called to notify that the application has begun to exit.
-  void OnApplicationTerminating();
-
- private:
-  FRIEND_TEST_ALL_PREFIXES(::SavedFilesServiceUnitTest, RetainTwoFilesTest);
-  FRIEND_TEST_ALL_PREFIXES(::SavedFilesServiceUnitTest, EvictionTest);
-  FRIEND_TEST_ALL_PREFIXES(::SavedFilesServiceUnitTest,
-                           SequenceNumberCompactionTest);
-  friend class ::SavedFilesServiceUnitTest;
-
-  // A container for the registered files for an app.
-  class SavedFiles;
-
-  // content::NotificationObserver.
-  void Observe(int type,
-               const content::NotificationSource& source,
-               const content::NotificationDetails& details) override;
-
-  // Returns the SavedFiles for |extension_id| or NULL if one does not exist.
-  SavedFiles* Get(const std::string& extension_id) const;
-
-  // Returns the SavedFiles for |extension_id|, creating it if necessary.
-  SavedFiles* GetOrInsert(const std::string& extension_id);
-
-  // Clears the SavedFiles for |extension_id|.
-  void Clear(const std::string& extension_id);
-
-  static void SetMaxSequenceNumberForTest(int max_value);
-  static void ClearMaxSequenceNumberForTest();
-  static void SetLruSizeForTest(int size);
-  static void ClearLruSizeForTest();
-
-  std::map<std::string, std::unique_ptr<SavedFiles>>
-      extension_id_to_saved_files_;
-  content::NotificationRegistrar registrar_;
-  content::BrowserContext* context_;
-
-  DISALLOW_COPY_AND_ASSIGN(SavedFilesService);
+  // nullptr if the file entry has not been registered.
+  virtual const Entry* GetFileEntry(const std::string& extension_id,
+                                    const std::string& id) = 0;
 };
 
-}  // namespace apps
+}  // namespace extensions
 
-#endif  // APPS_SAVED_FILES_SERVICE_H_
+#endif  // EXTENSIONS_BROWSER_API_FILE_SYSTEM_SAVED_FILES_SERVICE_H_