Basic implementation of GeofencingManager class.

content/browser/geofencing/geofencing_manager.h

+// Copyright 2014 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 CONTENT_BROWSER_GEOFENCING_GEOFENCING_MANAGER_H_
+#define CONTENT_BROWSER_GEOFENCING_GEOFENCING_MANAGER_H_
+
+#include <map>
+#include <string>
+
+#include "base/callback_forward.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "content/common/content_export.h"
+#include "content/common/geofencing_status.h"
+
+template <typename T>
+struct DefaultSingletonTraits;
+
+namespace blink {
+struct WebCircularGeofencingRegion;
+};
+
+namespace content {
+
+class GeofencingProvider;
+
+// This is the main API to the geofencing subsystem. The application will hold
+// a single instance of this class.
+// This class is responsible for keeping track of which geofences are currently
+// registered by websites/workers, persisting this list of registrations and
+// registering a subset of these active registrations with the underlying
+// platform specific |GeofencingProvider| instance.
+// This class lives on the IO thread, and all public methods of it should only
+// ever be called from that same thread.
+// FIXME: Does it make more sense for this to live on the UI thread instead of
+//     the IO thread?
+// TODO(mek): Implement some kind of persistence of registrations.
+// TODO(mek): Limit the number of geofences that are registered with the
+//    underlying GeofencingProvider.
+class CONTENT_EXPORT GeofencingManager {
+ public:
+  typedef base::Callback<void(GeofencingStatus)> StatusCallback;
+  typedef base::Callback<void(
+      GeofencingStatus,
+      const std::map<std::string, blink::WebCircularGeofencingRegion>&)>
+      RegistrationsCallback;
+
+  // Gets a pointer to the singleton instance of the geofencing manager. This
+  // must only be called on the IO thread so that the GeofencingManager is
+  // always instantiated on the same thread. Ownership is NOT returned.
+  static GeofencingManager* GetInstance();
+
+  // Initiates registration of a new geofence. StatusCallback is called when
+  // registration has completed or failed (which could possibly be before
+  // RegisterRegion returns.
+  // Attempting to register a region with the same ID as an already registered
+  // (or in progress of being registered) region will fail.
+  // TODO(mek): Behavior when using an already used ID might need to be revised
+  //     depending on what the actual spec ends up saying about this.
+  void RegisterRegion(int64 service_worker_registration_id,
+                      const std::string& region_id,
+                      const blink::WebCircularGeofencingRegion& region,
+                      const StatusCallback& callback);
+
+  // Unregister a region that was previously registered by a call to
+  // RegisterRegion. Any attempt to unregister a region that has not been
+  // registered, or for which the registration is still in progress
+  // (RegisterRegion hasn't called its callback yet) will fail.
+  // TODO(mek): Maybe better behavior would be to allow unregistering still
+  //     in-progress registrations.
+  void UnregisterRegion(int64 service_worker_registration_id,
+                        const std::string& region_id,
+                        const StatusCallback& callback);
+
+  // Returns all currently registered regions. In case of failure (no geofencing
+  // provider available for example) return an error status, while leaving
+  // |regions| untouched.
+  // This only returns regions for which the callback passed to RegisterRegion
+  // has been called already (so it doesn't include still in progress
+  // registrations).
+  GeofencingStatus GetRegisteredRegions(
+      int64 service_worker_registration_id,
+      std::map<std::string, blink::WebCircularGeofencingRegion>* regions);
+
+  void SetProviderForTests(scoped_ptr<GeofencingProvider> provider);
+
+ protected:
+  friend struct DefaultSingletonTraits<GeofencingManager>;
+  friend class GeofencingManagerTest;
+  GeofencingManager();
+  virtual ~GeofencingManager();
+
+ private:
+  // Called by GeofencingProvider when the platform specific provider completes
+  // registration of a geofence.
+  void RegisterRegionCompleted(const StatusCallback& callback,
+                               int64 service_worker_registration_id,
+                               const std::string& region_id,
+                               GeofencingStatus status,
+                               int registration_id);
+
+  // Internal bookkeeping associated with each registered geofence.
+  struct Registration;
+  // Mapping of region ID to Registration for all fences associated with a
+  // specific service worker.
+  typedef std::map<std::string, Registration> IdRegistrationMap;
+  // Mapping of Service Worker registration ID to map of its geofence
+  // registrations.
+  typedef std::map<int64, IdRegistrationMap> Registrations;

[Michael van Ouwerkerk, 2014/10/06 16:43:42]

A ServiceWorkerRegistrationId is unique per-origin. GeofencingManager is a
browser process singleton. Isn't this going to conflict when multiple renderers
with the same sw id (but different origins) lead to this map?

[Marijn Kruisselbrink, 2014/10/06 19:14:11]

Hmm, yes, you're right. It does seem like this is indeed a 64 bit counter scoped
by storage partition. I somehow mistakenly assumed that the counters in
ServiceWorkerStorage were global, but of course they are scoped to a storage
partition.

For simplicity I now changed this to just storing a vector<Registration>, with a
TODO to improve the storage mechanism for better lookup/delete performance
(since all access to this list of registrations is hidden behind the
FindRegistration, AddRegistration and ClearRegistration methods anyway changing
the storage mechanism later won't require significant changes).

+
+  // Looks up a particular geofence registration. Returns nullptr if no
+  // registration with the given IDs exists.
+  Registration* FindRegistration(int64 service_worker_registration_id,
+                                 const std::string& region_id);
+
+  // Registers a new registration, returning a reference to the newly inserted
+  // object. Assumes no registration with the same IDs currently exists.
+  Registration& AddRegistration(
+      int64 service_worker_registration_id,
+      const std::string& region_id,
+      const blink::WebCircularGeofencingRegion& region);
+
+  // Clears a registration.
+  void ClearRegistration(int64 service_worker_registration_id,
+                         const std::string& region_id);
+
+  Registrations registrations_;
+
+  scoped_ptr<GeofencingProvider> provider_;
+
+  DISALLOW_COPY_AND_ASSIGN(GeofencingManager);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_GEOFENCING_GEOFENCING_MANAGER_H_