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