chromeos/network/geolocation_handler.h

   1 // Copyright (c) 2013 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 CHROMEOS_NETWORK_GEOLOCATION_HANDLER_H_
   6 #define CHROMEOS_NETWORK_GEOLOCATION_HANDLER_H_
   7
   8 #include "base/memory/weak_ptr.h"
   9 #include "base/time.h"
  10 #include "chromeos/dbus/dbus_method_call_status.h"
  11 #include "chromeos/dbus/shill_property_changed_observer.h"
  12 #include "chromeos/network/network_util.h"
  13
  14 namespace base {
  15 class DictionaryValue;
  16 }
  17
  18 namespace chromeos {
  19
  20 // This class provices Shill Wifi Access Point data. It currently relies on
  21 // polling because that is the usage model in content::WifiDataProvider. This
  22 // class requests data asynchronously, returning the most recent available data.
  23 // A typical usage pattern, assuming a wifi device is enabled, is:
  24 //   Initialize();  // Makes an initial request
  25 //   GetWifiAccessPoints();  // returns true + inital data, requests update
  26 //   (Delay some amount of time, ~10s)
  27 //   GetWifiAccessPoints();  // returns true + updated data, requests update
  28 //   (Delay some amount of time after data changed, ~10s)
  29 //   GetWifiAccessPoints();  // returns true + same data, requests update
  30 //   (Delay some amount of time after data did not change, ~2 mins)
  31
  32 class CHROMEOS_EXPORT GeolocationHandler : public ShillPropertyChangedObserver {
  33  public:
  34   virtual ~GeolocationHandler();
  35
  36   // Manage the global instance. Must be initialized before any calls to Get().
  37   static void Initialize();
  38   static void Shutdown();
  39   static GeolocationHandler* Get();
  40
  41   // This sends a request for wifi access point data. If data is already
  42   // available, returns |true|, fills |access_points| with the latest access
  43   // point data, and sets |age_ms| to the time since the last update in MS.
  44   bool GetWifiAccessPoints(WifiAccessPointVector* access_points, int64* age_ms);
  45
  46   bool wifi_enabled() const { return wifi_enabled_; }
  47
  48   // ShillPropertyChangedObserver overrides
  49   virtual void OnPropertyChanged(const std::string& key,
  50                                  const base::Value& value) OVERRIDE;
  51
  52  private:
  53   friend class GeolocationHandlerTest;
  54   GeolocationHandler();
  55   void Init();
  56
  57   // ShillManagerClient callback
  58   void ManagerPropertiesCallback(DBusMethodCallStatus call_status,
  59                                  const base::DictionaryValue& properties);
  60
  61   // Called from OnPropertyChanged or ManagerPropertiesCallback.
  62   void HandlePropertyChanged(const std::string& key, const base::Value& value);
  63
  64   // Asynchronously request wifi access points from Shill.Manager.
  65   void RequestWifiAccessPoints();
  66
  67   // Callback for receiving Geolocation data.
  68   void GeolocationCallback(DBusMethodCallStatus call_status,
  69                            const base::DictionaryValue& properties);
  70
  71   // Wifi enabled state
  72   bool wifi_enabled_;
  73
  74   // Cached wifi access points and update time
  75   WifiAccessPointVector wifi_access_points_;
  76   base::Time geolocation_received_time_;
  77
  78   // For Shill client callbacks
  79   base::WeakPtrFactory<GeolocationHandler> weak_ptr_factory_;
  80
  81   DISALLOW_COPY_AND_ASSIGN(GeolocationHandler);
  82 };
  83
  84 }  // namespace chromeos
  85
  86 #endif  // CHROMEOS_NETWORK_GEOLOCATION_HANDLER_H_