component_loader.h revision 4e180b6a0b4720a9b8e9e959a882386f690f08ff 
1// Copyright (c) 2012 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 CHROME_BROWSER_EXTENSIONS_COMPONENT_LOADER_H_
6#define CHROME_BROWSER_EXTENSIONS_COMPONENT_LOADER_H_
7
8#include <string>
9#include <vector>
10
11#include "base/files/file_path.h"
12#include "base/gtest_prod_util.h"
13#include "base/values.h"
14
15class ExtensionServiceInterface;
16class PrefService;
17
18namespace extensions {
19
20// For registering, loading, and unloading component extensions.
21class ComponentLoader {
22 public:
23  ComponentLoader(ExtensionServiceInterface* extension_service,
24                  PrefService* prefs,
25                  PrefService* local_state);
26  virtual ~ComponentLoader();
27
28  size_t registered_extensions_count() const {
29    return component_extensions_.size();
30  }
31
32  // Creates and loads all registered component extensions.
33  void LoadAll();
34
35  // Registers and possibly loads a component extension. If ExtensionService
36  // has been initialized, the extension is loaded; otherwise, the load is
37  // deferred until LoadAll is called. The ID of the added extension is
38  // returned.
39  //
40  // Component extension manifests must contain a "key" property with a unique
41  // public key, serialized in base64. You can create a suitable value with the
42  // following commands on a unixy system:
43  //
44  //   ssh-keygen -t rsa -b 1024 -N '' -f /tmp/key.pem
45  //   openssl rsa -pubout -outform DER < /tmp/key.pem 2>/dev/null | base64 -w 0
46  std::string Add(const std::string& manifest_contents,
47                  const base::FilePath& root_directory);
48
49  // Convenience method for registering a component extension by resource id.
50  std::string Add(int manifest_resource_id,
51                  const base::FilePath& root_directory);
52
53  // Loads a component extension from file system. Replaces previously added
54  // extension with the same ID.
55  std::string AddOrReplace(const base::FilePath& path);
56
57  // Returns the extension ID of a component extension specified by resource
58  // id of its manifest file.
59  std::string GetExtensionID(int manifest_resource_id,
60                             const base::FilePath& root_directory);
61
62  // Returns true if an extension with the specified id has been added.
63  bool Exists(const std::string& id) const;
64
65  // Unloads a component extension and removes it from the list of component
66  // extensions to be loaded.
67  void Remove(const base::FilePath& root_directory);
68  void Remove(const std::string& id);
69
70  // Call this during test setup to load component extensions that have
71  // background pages for testing, which could otherwise interfere with tests.
72  static void EnableBackgroundExtensionsForTesting();
73
74  // Adds the default component extensions. If |skip_session_components|
75  // the loader will skip loading component extensions that weren't supposed to
76  // be loaded unless we are in signed user session (ChromeOS). For all other
77  // platforms this |skip_session_components| is expected to be unset.
78  void AddDefaultComponentExtensions(bool skip_session_components);
79
80  // Parse the given JSON manifest. Returns NULL if it cannot be parsed, or if
81  // if the result is not a DictionaryValue.
82  DictionaryValue* ParseManifest(const std::string& manifest_contents) const;
83
84  // Clear the list of registered extensions.
85  void ClearAllRegistered();
86
87  // Reloads a registered component extension.
88  void Reload(const std::string& extension_id);
89
90 private:
91  // Information about a registered component extension.
92  struct ComponentExtensionInfo {
93    ComponentExtensionInfo(const DictionaryValue* manifest,
94                           const base::FilePath& root_directory);
95
96    // The parsed contents of the extensions's manifest file.
97    const DictionaryValue* manifest;
98
99    // Directory where the extension is stored.
100    base::FilePath root_directory;
101
102    // The component extension's ID.
103    std::string extension_id;
104  };
105
106  std::string Add(const DictionaryValue* parsed_manifest,
107                  const base::FilePath& root_directory);
108
109  // Loads a registered component extension.
110  void Load(const ComponentExtensionInfo& info);
111
112  void AddDefaultComponentExtensionsWithBackgroundPages(
113      bool skip_session_components);
114  void AddFileManagerExtension();
115  void AddImageLoaderExtension();
116  void AddBookmarksExtensions();
117
118  void AddWithName(int manifest_resource_id,
119                   const base::FilePath& root_directory,
120                   const std::string& name);
121  void AddChromeApp();
122  void AddKeyboardApp();
123  void AddWebStoreApp();
124
125  // Unloads |component| from the memory.
126  void UnloadComponent(ComponentExtensionInfo* component);
127
128  PrefService* profile_prefs_;
129  PrefService* local_state_;
130
131  ExtensionServiceInterface* extension_service_;
132
133  // List of registered component extensions (see Manifest::Location).
134  typedef std::vector<ComponentExtensionInfo> RegisteredComponentExtensions;
135  RegisteredComponentExtensions component_extensions_;
136
137  DISALLOW_COPY_AND_ASSIGN(ComponentLoader);
138};
139
140}  // namespace extensions
141
142#endif  // CHROME_BROWSER_EXTENSIONS_COMPONENT_LOADER_H_
143