1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef EXTENSIONS_BROWSER_API_STORAGE_VALUE_STORE_CACHE_H_ 6 #define EXTENSIONS_BROWSER_API_STORAGE_VALUE_STORE_CACHE_H_ 7 8 #include <string> 9 10 #include "base/callback.h" 11 #include "base/memory/ref_counted.h" 12 13 class ValueStore; 14 15 namespace extensions { 16 17 class Extension; 18 19 // Each namespace of the storage API implements this interface. 20 // Instances are created on the UI thread, but from then on live on the FILE 21 // thread. At shutdown, ShutdownOnUI() is first invoked on the UI thread, and 22 // the destructor is invoked soon after on the FILE thread. This gives 23 // implementations the chance to work with ValueStores on FILE but observe 24 // events on UI. 25 // It also means that any methods invoked on UI *before ShutdownOnUI()* can 26 // safely post other methods to the FILE thread, since the deletion task is only 27 // posted to FILE after ShutdownOnUI(). 28 class ValueStoreCache { 29 public: 30 typedef base::Callback<void(ValueStore*)> StorageCallback; 31 32 // Invoked on FILE. 33 virtual ~ValueStoreCache(); 34 35 // This is invoked from the UI thread during destruction of the Profile that 36 // ultimately owns this object. Any Profile-related cleanups should be 37 // performed in this method, since the destructor will execute later, after 38 // the Profile is already gone. 39 virtual void ShutdownOnUI(); 40 41 // Requests the cache to invoke |callback| with the appropriate ValueStore 42 // for the given |extension|. |callback| should be invoked with a NULL 43 // ValueStore in case of errors. 44 // |extension| is passed in a scoped_refptr<> because this method is 45 // asynchronously posted as a task to the loop returned by GetMessageLoop(), 46 // and this guarantees the Extension is still valid when the method executes. 47 virtual void RunWithValueStoreForExtension( 48 const StorageCallback& callback, 49 scoped_refptr<const Extension> extension) = 0; 50 51 // Requests the cache to delete any storage used by |extension_id|. 52 virtual void DeleteStorageSoon(const std::string& extension_id) = 0; 53 }; 54 55 } // namespace extensions 56 57 #endif // EXTENSIONS_BROWSER_API_STORAGE_VALUE_STORE_CACHE_H_ 58
