Implement fetching, caching and retrieval of external policy data

chrome/browser/policy/cloud/cloud_policy_store.h

 // Copyright (c) 2012 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_CLOUD_POLICY_STORE_H_
 #define CHROME_BROWSER_POLICY_CLOUD_CLOUD_POLICY_STORE_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "chrome/browser/policy/cloud/cloud_policy_validator.h"
 #include "chrome/browser/policy/policy_map.h"
 #include "chrome/browser/policy/proto/cloud/device_management_backend.pb.h"
 
 namespace policy {
 
+class CloudExternalDataManager;
+
 // Defines the low-level interface used by the cloud policy code to:
 //   1. Validate policy blobs that should be applied locally
 //   2. Persist policy blobs
 //   3. Decode policy blobs to PolicyMap representation
 class CloudPolicyStore {
  public:
   // Status codes.
   enum Status {
     // Everything is in good order.
     STATUS_OK,
@@ skipping 23 matching lines @@
     virtual void OnStoreError(CloudPolicyStore* store) = 0;
   };
 
   CloudPolicyStore();
   virtual ~CloudPolicyStore();
 
   // Indicates whether the store has been fully initialized. This is
   // accomplished by calling Load() after startup.
   bool is_initialized() const { return is_initialized_; }
 
+  base::WeakPtr<CloudExternalDataManager> external_data_manager() const {
+    return external_data_manager_;
+  }
+
   const PolicyMap& policy_map() const { return policy_map_; }
   bool has_policy() const {
     return policy_.get() != NULL;
   }
   const enterprise_management::PolicyData* policy() const {
     return policy_.get();
   }
   bool is_managed() const {
     return policy_.get() &&
            policy_->state() == enterprise_management::PolicyData::ACTIVE;
@@ skipping 16 matching lines @@
   // Upon success, OnStoreLoaded() will be called on the registered observers.
   // Otherwise, OnStoreError() reports the reason for failure.
   virtual void Load() = 0;
 
   // Registers an observer to be notified when policy changes.
   void AddObserver(Observer* observer);
 
   // Removes the specified observer.
   void RemoveObserver(Observer* observer);
 
+  // Indicate that external data referenced by policies in this store is managed
+  // by |external_data_manager|. The |external_data_manager| will be notified
+  // about policy changes before any other observers.
+  void SetExternalDataManager(
+      base::WeakPtr<CloudExternalDataManager> external_data_manager);
+
  protected:
   // Invokes the corresponding callback on all registered observers.
   void NotifyStoreLoaded();
   void NotifyStoreError();
 
+  // Manages external data referenced by policies.
+  base::WeakPtr<CloudExternalDataManager> external_data_manager_;
+
   // Decoded version of the currently effective policy.
   PolicyMap policy_map_;
 
   // Currently effective policy.
   scoped_ptr<enterprise_management::PolicyData> policy_;
 
   // Latest status code.
   Status status_;
 
   // Latest validation status.
   CloudPolicyValidatorBase::Status validation_status_;
 
  private:
   // Whether the store has completed asynchronous initialization, which is
   // triggered by calling Load().
   bool is_initialized_;
 
   ObserverList<Observer, true> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(CloudPolicyStore);
 };
 
 }  // namespace policy
 
 #endif  // CHROME_BROWSER_POLICY_CLOUD_CLOUD_POLICY_STORE_H_