Add ExtensionManagement class

chrome/browser/extensions/extension_management.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_MANAGEMENT_H_
+#define CHROME_BROWSER_EXTENSIONS_EXTENSION_MANAGEMENT_H_
+
+#include <map>
+#include <string>
+#include <vector>
+
+#include "base/macros.h"
+#include "base/values.h"
+#include "extensions/common/extension.h"
+#include "extensions/common/manifest.h"
+#include "extensions/common/url_pattern_set.h"
+
+class PrefService;
+
+namespace extensions {
+
+// Tracks the management policies that affect extensions and provides interfaces
+// for observing and obtaining the global settings for all extensions, as well
+// as per-extension settings.
+class ExtensionManagement {
+ public:
+  // Installation mode for extensions, default is INSTALLATION_ALLOWED.
+  // * INSTALLATION_ALLOWED: Extension can be installed.
+  // * INSTALLATION_BLOCKED: Extension cannot be installed.
+  // * INSTALLATION_FORCED: Extension will be installed automatically
+  //                        and cannot be disabled.
+  // * INSTALLATION_RECOMMENDED: Extension will be installed automatically but
+  //                             can be disabled.
+  enum InstallationMode {
+    INSTALLATION_ALLOWED = 0,
+    INSTALLATION_BLOCKED,
+    INSTALLATION_FORCED,
+    INSTALLATION_RECOMMENDED,
+  };
+
+  // Class to hold extension management settings for one or a group of
+  // extensions. Settings can be applied to an individual extension identified
+  // by an ID, a group of extensions with specific |update_url| or all
+  // extensions at once.
+  struct IndividualSettings {
+    void Reset();
+
+    InstallationMode installation_mode;
+    std::string update_url;

[Finnur, 2014/09/03 13:04:01]

nit: document.

[binjin, 2014/09/03 14:31:55]

Done.

+  };
+
+  // Global extension management settings, applicable to all extensions.
+  struct GlobalSettings {
+    GlobalSettings();
+    ~GlobalSettings();
+
+    void Reset();
+
+    URLPatternSet install_sources;
+    bool has_restricted_install_sources;
+
+    std::vector<Manifest::Type> allowed_types;
+    bool has_restricted_allowed_types;

[Finnur, 2014/09/03 13:04:01]

nit: document all these.

[binjin, 2014/09/03 14:31:55]

Done.

+  };
+
+  typedef std::map<ExtensionId, IndividualSettings> SettingsIdMap;
+
+  explicit ExtensionManagement(PrefService* pref_service);
+  virtual ~ExtensionManagement();
+
+  // Load all extension management preferences from |pref_service|, and
+  // refresh the settings.
+  void Refresh();
+
+  // Helper function to read |settings_by_id_| with |id| as key. Returns a
+  // constant reference to default settings if |id| does not exist.
+  const IndividualSettings& ReadById(const ExtensionId& id) const;
+
+  // Returns a constant reference to |global_settings_|.
+  const GlobalSettings& ReadGlobalSettings() const;
+
+ private:
+  // Load preference with name |pref_name| and expected type |expected_type|.
+  // If |force_managed| is true, only loading from the managed preference store
+  // is allowed. Returns NULL if the preference is not present, not allowed to
+  // be loaded from or has the wrong type.
+  const base::Value* LoadPreference(const char* pref_name,
+                                    bool force_managed,
+                                    base::Value::Type expected_type);
+
+  // Helper function to access |settings_by_id_| with |id| as key.
+  // Adds a new IndividualSettings entry to |settings_by_id_| if none exists for
+  // |id| yet.
+  IndividualSettings* AccessById(const ExtensionId& id);
+
+  // TODO(binjin): Add |settings_by_update_url_|, and implement mechanism for
+  // it.
+  SettingsIdMap settings_by_id_;
+  IndividualSettings default_settings_;
+  GlobalSettings global_settings_;

[Finnur, 2014/09/03 13:04:01]

nit: Document. 

In my experience, this only invites headaches down the road when people see this
list and think "well, I guess I don't need to document the subtle member *I'm*
adding, because all these members I have no knowledge about are not documented
either".

[binjin, 2014/09/03 14:31:55]

Done.

+
+  PrefService* pref_service_;
+
+  DISALLOW_COPY_AND_ASSIGN(ExtensionManagement);
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_MANAGEMENT_H_