extensions/common/features/simple_feature_filter.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_COMMON_FEATURES_SIMPLE_FEATURE_FILTER_H_
   6 #define EXTENSIONS_COMMON_FEATURES_SIMPLE_FEATURE_FILTER_H_
   7
   8 #include <string>
   9
  10 #include "extensions/common/features/feature.h"
  11 #include "extensions/common/manifest.h"
  12
  13 class GURL;
  14
  15 namespace base {
  16 class DictionaryValue;
  17 }
  18
  19 namespace extensions {
  20
  21 class SimpleFeature;
  22
  23 // A SimpleFeatureFilter can be attached to SimpleFeature objects to provide
  24 // additional parsing and availability filtering behavior.
  25 class SimpleFeatureFilter {
  26  public:
  27   explicit SimpleFeatureFilter(SimpleFeature* feature);
  28   virtual ~SimpleFeatureFilter();
  29
  30   SimpleFeature* feature() const { return feature_; }
  31
  32   // Parses any additional feature data that may be used by this filter.
  33   // Returns an error string on failure or the empty string on success.
  34   // The default implementation simply returns the empty string.
  35   virtual std::string Parse(const base::DictionaryValue* value);
  36
  37   // Indicates whether or not the owning feature is available within a given
  38   // extensions context. The default implementation only affirms availability.
  39   virtual Feature::Availability IsAvailableToContext(
  40       const Extension* extension,
  41       Feature::Context context,
  42       const GURL& url,
  43       Feature::Platform platform) const;
  44
  45   // Indicates whether or not the owning feature is available to a given
  46   // extension manifest. The default implementation only affirms availability.
  47   virtual Feature::Availability IsAvailableToManifest(
  48       const std::string& extension_id,
  49       Manifest::Type type,
  50       Manifest::Location location,
  51       int manifest_version,
  52       Feature::Platform platform) const;
  53
  54  private:
  55   // The feature which owns this filter.
  56   SimpleFeature* feature_;
  57
  58   DISALLOW_COPY_AND_ASSIGN(SimpleFeatureFilter);
  59 };
  60
  61 }  // namespace extensions
  62
  63 #endif  // EXTENSIONS_COMMON_FEATURES_SIMPLE_FEATURE_FILTER_H_