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 COMPONENTS_POLICY_CORE_COMMON_CLOUD_CLOUD_POLICY_REFRESH_SCHEDULER_H_ 6 #define COMPONENTS_POLICY_CORE_COMMON_CLOUD_CLOUD_POLICY_REFRESH_SCHEDULER_H_ 7 8 #include "base/basictypes.h" 9 #include "base/cancelable_callback.h" 10 #include "base/memory/ref_counted.h" 11 #include "base/time/time.h" 12 #include "components/policy/core/common/cloud/cloud_policy_client.h" 13 #include "components/policy/core/common/cloud/cloud_policy_store.h" 14 #include "components/policy/core/common/cloud/rate_limiter.h" 15 #include "components/policy/policy_export.h" 16 #include "net/base/network_change_notifier.h" 17 18 namespace base { 19 class SequencedTaskRunner; 20 } 21 22 namespace policy { 23 24 // Observes CloudPolicyClient and CloudPolicyStore to trigger periodic policy 25 // fetches and issue retries on error conditions. 26 class POLICY_EXPORT CloudPolicyRefreshScheduler 27 : public CloudPolicyClient::Observer, 28 public CloudPolicyStore::Observer, 29 public net::NetworkChangeNotifier::IPAddressObserver { 30 public: 31 // Refresh constants. 32 static const int64 kDefaultRefreshDelayMs; 33 static const int64 kUnmanagedRefreshDelayMs; 34 static const int64 kWithInvalidationsRefreshDelayMs; 35 static const int64 kInitialErrorRetryDelayMs; 36 37 // Refresh delay bounds. 38 static const int64 kRefreshDelayMinMs; 39 static const int64 kRefreshDelayMaxMs; 40 41 // |client| and |store| pointers must stay valid throughout the 42 // lifetime of CloudPolicyRefreshScheduler. 43 CloudPolicyRefreshScheduler( 44 CloudPolicyClient* client, 45 CloudPolicyStore* store, 46 const scoped_refptr<base::SequencedTaskRunner>& task_runner); 47 virtual ~CloudPolicyRefreshScheduler(); 48 49 base::Time last_refresh() const { return last_refresh_; } 50 int64 refresh_delay() const { return refresh_delay_ms_; } 51 52 // Sets the refresh delay to |refresh_delay| (subject to min/max clamping). 53 void SetRefreshDelay(int64 refresh_delay); 54 55 // Requests a policy refresh to be performed soon. This may apply throttling, 56 // and the request may not be immediately sent. 57 void RefreshSoon(); 58 59 // The refresh scheduler starts by assuming that invalidations are not 60 // available. This call can be used to signal whether the invalidations 61 // service is available or not, and can be called multiple times. 62 // When the invalidations service is available then the refresh rate is much 63 // lower. 64 void SetInvalidationServiceAvailability(bool is_available); 65 66 // Whether the invalidations service is available and receiving notifications 67 // of policy updates. 68 bool invalidations_available() { 69 return invalidations_available_; 70 } 71 72 // CloudPolicyClient::Observer: 73 virtual void OnPolicyFetched(CloudPolicyClient* client) OVERRIDE; 74 virtual void OnRegistrationStateChanged(CloudPolicyClient* client) OVERRIDE; 75 virtual void OnClientError(CloudPolicyClient* client) OVERRIDE; 76 77 // CloudPolicyStore::Observer: 78 virtual void OnStoreLoaded(CloudPolicyStore* store) OVERRIDE; 79 virtual void OnStoreError(CloudPolicyStore* store) OVERRIDE; 80 81 // net::NetworkChangeNotifier::IPAddressObserver: 82 virtual void OnIPAddressChanged() OVERRIDE; 83 84 private: 85 // Initializes |last_refresh_| to the policy timestamp from |store_| in case 86 // there is policy present that indicates this client is not managed. This 87 // results in policy fetches only to occur after the entire unmanaged refresh 88 // delay expires, even over restarts. For managed clients, we want to trigger 89 // a refresh on every restart. 90 void UpdateLastRefreshFromPolicy(); 91 92 // Schedules a refresh to be performed immediately. 93 void RefreshNow(); 94 95 // Evaluates when the next refresh is pending and updates the callback to 96 // execute that refresh at the appropriate time. 97 void ScheduleRefresh(); 98 99 // Triggers a policy refresh. 100 void PerformRefresh(); 101 102 // Schedules a policy refresh to happen after |delta_ms| milliseconds, 103 // relative to |last_refresh_|. 104 void RefreshAfter(int delta_ms); 105 106 // Sets the |wait_for_invalidations_timeout_callback_| and schedules it. 107 void WaitForInvalidationService(); 108 109 // Callback for |wait_for_invalidations_timeout_callback_|. 110 void OnWaitForInvalidationServiceTimeout(); 111 112 // Returns true if the refresh scheduler is currently waiting for the 113 // availability of the invalidations service. 114 bool WaitingForInvalidationService() const; 115 116 CloudPolicyClient* client_; 117 CloudPolicyStore* store_; 118 119 // For scheduling delayed tasks. 120 const scoped_refptr<base::SequencedTaskRunner> task_runner_; 121 122 // The delayed refresh callback. 123 base::CancelableClosure refresh_callback_; 124 125 // The last time a refresh callback completed. 126 base::Time last_refresh_; 127 128 // Error retry delay in milliseconds. 129 int64 error_retry_delay_ms_; 130 131 // The refresh delay. 132 int64 refresh_delay_ms_; 133 134 // Used to limit the rate at which refreshes are scheduled. 135 RateLimiter rate_limiter_; 136 137 // Whether the invalidations service is available and receiving notifications 138 // of policy updates. 139 bool invalidations_available_; 140 141 // The refresh scheduler waits some seconds for the invalidations service 142 // before starting to issue refresh requests. If the invalidations service 143 // doesn't become available during this time then the refresh scheduler will 144 // use the polling refresh rate. 145 base::CancelableClosure wait_for_invalidations_timeout_callback_; 146 147 // Used to measure how long it took for the invalidations service to report 148 // its initial status. 149 base::Time creation_time_; 150 151 DISALLOW_COPY_AND_ASSIGN(CloudPolicyRefreshScheduler); 152 }; 153 154 } // namespace policy 155 156 #endif // COMPONENTS_POLICY_CORE_COMMON_CLOUD_CLOUD_POLICY_REFRESH_SCHEDULER_H_ 157
