Consolidate data storage and notifications in the cloud policy subsystem

chrome/browser/policy/cloud_policy_identity_strategy.h

-// Copyright (c) 2011 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_POLICY_CLOUD_POLICY_IDENTITY_STRATEGY_H_
-#define CHROME_BROWSER_POLICY_CLOUD_POLICY_IDENTITY_STRATEGY_H_
-#pragma once
-
-#include <string>
-
-#include "base/observer_list.h"
-#include "chrome/browser/policy/proto/device_management_backend.pb.h"
-
-namespace policy {
-
-namespace em = enterprise_management;
-
-// Manages a device management token, i.e. an identifier that represents a
-// registration with the device management service, and the associated
-// credentials. Responsibilities include storing and loading the token from
-// disk, observing and triggering relevant notifications.
-class CloudPolicyIdentityStrategy {
- public:
-  class Observer {
-   public:
-    virtual ~Observer() {}
-
-    // Notifies observers that the effective token for fetching policy has
-    // changed. The token can be queried by calling GetDeviceToken().
-    virtual void OnDeviceTokenChanged() = 0;
-
-    // Authentication credentials for talking to the device management service
-    // changed. New auth data is available through GetCredentials().
-    virtual void OnCredentialsChanged() = 0;
-  };
-
-  CloudPolicyIdentityStrategy();
-  virtual ~CloudPolicyIdentityStrategy();
-
-  void AddObserver(Observer* obs);
-  void RemoveObserver(Observer* obs);
-
-  // Returns the device management token, if available. Returns the empty string
-  // if the device token is currently unavailable.
-  virtual std::string GetDeviceToken() = 0;
-
-  // Returns the device ID for this device. This is a unique identifier that is
-  // randomly generated at registration time on the client side. It always has
-  // to be sent along with the device token to the server.
-  virtual std::string GetDeviceID() = 0;
-
-  // Returns physical machine ID for this device.
-  virtual std::string GetMachineID() = 0;
-
-  // Returns physical machine model for this device.
-  virtual std::string GetMachineModel() = 0;
-
-  // Returns the policy type to be used for registering at the device management
-  // server.
-  virtual em::DeviceRegisterRequest_Type GetPolicyRegisterType() = 0;
-
-  // Returns the policy type to be used for requesting policies from the device
-  // management server.
-  virtual std::string GetPolicyType() = 0;
-
-  // Retrieves authentication credentials to use when talking to the device
-  // management service. Returns true if the data is available and writes the
-  // values to the provided pointers.
-  virtual bool GetCredentials(std::string* username,
-                              std::string* auth_token) = 0;
-
-  // Notifies the identity strategy that a new token has been fetched. It is up
-  // to the identity strategy to store the token, decide whether it is going
-  // to be used, send out an appropriate OnDeviceTokenChanged() notification
-  // and return the new token in GetDeviceToken() calls.
-  virtual void OnDeviceTokenAvailable(const std::string& token) = 0;
-
- protected:
-  // Notify observers that the effective token has changed.
-  void NotifyDeviceTokenChanged();
-
-  // Notify observers about authentication data change.
-  void NotifyAuthChanged();
-
- private:
-  ObserverList<Observer, true> observer_list_;
-
-  DISALLOW_COPY_AND_ASSIGN(CloudPolicyIdentityStrategy);
-};
-
-}  // namespace policy
-
-#endif  // CHROME_BROWSER_POLICY_CLOUD_POLICY_IDENTITY_STRATEGY_H_