extensions/common/feature_switch.h

   1 // Copyright 2013 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_COMMON_FEATURE_SWITCH_H_
   6 #define EXTENSIONS_COMMON_FEATURE_SWITCH_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11
  12 namespace base {
  13 class CommandLine;
  14 }
  15
  16 namespace extensions {
  17
  18 // A switch that can turn a feature on or off. Typically controlled via
  19 // command-line switches but can be overridden, e.g., for testing.
  20 class FeatureSwitch {
  21  public:
  22   static FeatureSwitch* easy_off_store_install();
  23   static FeatureSwitch* force_dev_mode_highlighting();
  24   static FeatureSwitch* prompt_for_external_extensions();
  25   static FeatureSwitch* error_console();
  26   static FeatureSwitch* enable_override_bookmarks_ui();
  27   static FeatureSwitch* extension_action_redesign();
  28   static FeatureSwitch* scripts_require_action();
  29   static FeatureSwitch* embedded_extension_options();
  30   static FeatureSwitch* surface_worker();
  31   static FeatureSwitch* trace_app_source();
  32
  33   enum DefaultValue {
  34     DEFAULT_ENABLED,
  35     DEFAULT_DISABLED
  36   };
  37
  38   enum OverrideValue {
  39     OVERRIDE_NONE,
  40     OVERRIDE_ENABLED,
  41     OVERRIDE_DISABLED
  42   };
  43
  44   // A temporary override for the switch value.
  45   class ScopedOverride {
  46    public:
  47     ScopedOverride(FeatureSwitch* feature, bool override_value);
  48     ~ScopedOverride();
  49    private:
  50     FeatureSwitch* feature_;
  51     FeatureSwitch::OverrideValue previous_value_;
  52     DISALLOW_COPY_AND_ASSIGN(ScopedOverride);
  53   };
  54
  55   // |switch_name| can be NULL, in which case the feature is controlled solely
  56   // by the default and override values.
  57   FeatureSwitch(const char* switch_name,
  58                 DefaultValue default_value);
  59   FeatureSwitch(const base::CommandLine* command_line,
  60                 const char* switch_name,
  61                 DefaultValue default_value);
  62
  63   // Consider using ScopedOverride instead.
  64   void SetOverrideValue(OverrideValue value);
  65   OverrideValue GetOverrideValue() const;
  66
  67   bool IsEnabled() const;
  68
  69  private:
  70   void Init(const base::CommandLine* command_line,
  71             const char* switch_name,
  72             DefaultValue default_value);
  73
  74   std::string GetLegacyEnableFlag() const;
  75   std::string GetLegacyDisableFlag() const;
  76
  77   const base::CommandLine* command_line_;
  78   const char* switch_name_;
  79   bool default_value_;
  80   OverrideValue override_value_;
  81
  82   DISALLOW_COPY_AND_ASSIGN(FeatureSwitch);
  83 };
  84
  85 }  // namespace extensions
  86
  87 #endif  // EXTENSIONS_COMMON_FEATURE_SWITCH_H_