extensions/browser/api/storage/storage_api.h

   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_STORAGE_API_H_
   6 #define EXTENSIONS_BROWSER_API_STORAGE_STORAGE_API_H_
   7
   8 #include "base/compiler_specific.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "extensions/browser/api/storage/settings_namespace.h"
  11 #include "extensions/browser/api/storage/settings_observer.h"
  12 #include "extensions/browser/extension_function.h"
  13 #include "extensions/browser/value_store/value_store.h"
  14
  15 namespace extensions {
  16
  17 // Superclass of all settings functions.
  18 class SettingsFunction : public UIThreadExtensionFunction {
  19  protected:
  20   SettingsFunction();
  21   virtual ~SettingsFunction();
  22
  23   // ExtensionFunction:
  24   virtual bool ShouldSkipQuotaLimiting() const OVERRIDE;
  25   virtual ResponseAction Run() OVERRIDE;
  26
  27   // Extension settings function implementations should do their work here.
  28   // The StorageFrontend makes sure this is posted to the appropriate thread.
  29   virtual ResponseValue RunWithStorage(ValueStore* storage) = 0;
  30
  31   // Handles the |result| of a read function.
  32   // - If the result succeeded, this will set |result_| and return.
  33   // - If |result| failed with a ValueStore::CORRUPTION error, this will call
  34   //   RestoreStorageAndRetry(), and return that result.
  35   // - If the |result| failed with a different error, this will set |error_|
  36   //   and return.
  37   ResponseValue UseReadResult(ValueStore::ReadResult result,
  38                               ValueStore* storage);
  39
  40   // Handles the |result| of a write function.
  41   // - If the result succeeded, this will set |result_| and return.
  42   // - If |result| failed with a ValueStore::CORRUPTION error, this will call
  43   //   RestoreStorageAndRetry(), and return that result.
  44   // - If the |result| failed with a different error, this will set |error_|
  45   //   and return.
  46   // This will also send out a change notification, if appropriate.
  47   ResponseValue UseWriteResult(ValueStore::WriteResult result,
  48                                ValueStore* storage);
  49
  50  private:
  51   // Called via PostTask from Run. Calls RunWithStorage and then
  52   // SendResponse with its success value.
  53   void AsyncRunWithStorage(ValueStore* storage);
  54
  55   // Called if we encounter a ValueStore error. If the error is due to
  56   // corruption, tries to restore the ValueStore and re-run the API function.
  57   // If the storage cannot be restored or was due to some other error, then sets
  58   // error and returns. This also sets the |tried_restoring_storage_| flag to
  59   // ensure we don't enter a loop.
  60   ResponseValue HandleError(const ValueStore::Error& error,
  61                             ValueStore* storage);
  62
  63   // The settings namespace the call was for.  For example, SYNC if the API
  64   // call was chrome.settings.experimental.sync..., LOCAL if .local, etc.
  65   settings_namespace::Namespace settings_namespace_;
  66
  67   // A flag indicating whether or not we have tried to restore storage. We
  68   // should only ever try once (per API call) in order to avoid entering a loop.
  69   bool tried_restoring_storage_;
  70
  71   // Observers, cached so that it's only grabbed from the UI thread.
  72   scoped_refptr<SettingsObserverList> observers_;
  73 };
  74
  75 class StorageStorageAreaGetFunction : public SettingsFunction {
  76  public:
  77   DECLARE_EXTENSION_FUNCTION("storage.get", STORAGE_GET)
  78
  79  protected:
  80   virtual ~StorageStorageAreaGetFunction() {}
  81
  82   // SettingsFunction:
  83   virtual ResponseValue RunWithStorage(ValueStore* storage) OVERRIDE;
  84 };
  85
  86 class StorageStorageAreaSetFunction : public SettingsFunction {
  87  public:
  88   DECLARE_EXTENSION_FUNCTION("storage.set", STORAGE_SET)
  89
  90  protected:
  91   virtual ~StorageStorageAreaSetFunction() {}
  92
  93   // SettingsFunction:
  94   virtual ResponseValue RunWithStorage(ValueStore* storage) OVERRIDE;
  95
  96   // ExtensionFunction:
  97   virtual void GetQuotaLimitHeuristics(
  98       QuotaLimitHeuristics* heuristics) const OVERRIDE;
  99 };
 100
 101 class StorageStorageAreaRemoveFunction : public SettingsFunction {
 102  public:
 103   DECLARE_EXTENSION_FUNCTION("storage.remove", STORAGE_REMOVE)
 104
 105  protected:
 106   virtual ~StorageStorageAreaRemoveFunction() {}
 107
 108   // SettingsFunction:
 109   virtual ResponseValue RunWithStorage(ValueStore* storage) OVERRIDE;
 110
 111   // ExtensionFunction:
 112   virtual void GetQuotaLimitHeuristics(
 113       QuotaLimitHeuristics* heuristics) const OVERRIDE;
 114 };
 115
 116 class StorageStorageAreaClearFunction : public SettingsFunction {
 117  public:
 118   DECLARE_EXTENSION_FUNCTION("storage.clear", STORAGE_CLEAR)
 119
 120  protected:
 121   virtual ~StorageStorageAreaClearFunction() {}
 122
 123   // SettingsFunction:
 124   virtual ResponseValue RunWithStorage(ValueStore* storage) OVERRIDE;
 125
 126   // ExtensionFunction:
 127   virtual void GetQuotaLimitHeuristics(
 128       QuotaLimitHeuristics* heuristics) const OVERRIDE;
 129 };
 130
 131 class StorageStorageAreaGetBytesInUseFunction : public SettingsFunction {
 132  public:
 133   DECLARE_EXTENSION_FUNCTION("storage.getBytesInUse", STORAGE_GETBYTESINUSE)
 134
 135  protected:
 136   virtual ~StorageStorageAreaGetBytesInUseFunction() {}
 137
 138   // SettingsFunction:
 139   virtual ResponseValue RunWithStorage(ValueStore* storage) OVERRIDE;
 140 };
 141
 142 }  // namespace extensions
 143
 144 #endif  // EXTENSIONS_BROWSER_API_STORAGE_STORAGE_API_H_