1 // Copyright 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.
5 #ifndef CHROME_BROWSER_INVALIDATION_INVALIDATION_SERVICE_H_
6 #define CHROME_BROWSER_INVALIDATION_INVALIDATION_SERVICE_H_
8 #include "components/browser_context_keyed_service/browser_context_keyed_service.h"
9 #include "sync/notifier/invalidation_util.h"
10 #include "sync/notifier/invalidator_state.h"
13 class InvalidationHandler;
16 namespace invalidation {
17 class InvalidationLogger;
19 // Interface for classes that handle invalidation registrations and send out
20 // invalidations to register handlers.
22 // Invalidation clients should follow the pattern below:
24 // When starting the client:
26 // frontend->RegisterInvalidationHandler(client_handler);
28 // When the set of IDs to register changes for the client during its lifetime
29 // (i.e., between calls to RegisterInvalidationHandler(client_handler) and
30 // UnregisterInvalidationHandler(client_handler):
32 // frontend->UpdateRegisteredInvalidationIds(client_handler, client_ids);
34 // When shutting down the client for browser shutdown:
36 // frontend->UnregisterInvalidationHandler(client_handler);
38 // Note that there's no call to UpdateRegisteredIds() -- this is because the
39 // invalidation API persists registrations across browser restarts.
41 // When permanently shutting down the client, e.g. when disabling the related
44 // frontend->UpdateRegisteredInvalidationIds(client_handler, ObjectIdSet());
45 // frontend->UnregisterInvalidationHandler(client_handler);
47 // If an invalidation handler cares about the invalidator state, it should also
48 // do the following when starting the client:
50 // invalidator_state = frontend->GetInvalidatorState();
52 // It can also do the above in OnInvalidatorStateChange(), or it can use the
53 // argument to OnInvalidatorStateChange().
55 // It is an error to have registered handlers when an
56 // InvalidationFrontend is shut down; clients must ensure that they
57 // unregister themselves before then. (Depending on the
58 // InvalidationFrontend, shutdown may be equivalent to destruction, or
59 // a separate function call like Shutdown()).
61 // NOTE(akalin): Invalidations that come in during browser shutdown may get
62 // dropped. This won't matter once we have an Acknowledge API, though: see
63 // http://crbug.com/78462 and http://crbug.com/124149.
65 // This class inherits from ProfileKeyedService to make it possible to correctly
66 // cast from various InvalidationService implementations to ProfileKeyedService
67 // in InvalidationServiceFactory.
68 class InvalidationService : public BrowserContextKeyedService {
70 // Starts sending notifications to |handler|. |handler| must not be NULL,
71 // and it must not already be registered.
73 // Handler registrations are persisted across restarts of sync.
74 virtual void RegisterInvalidationHandler(
75 syncer::InvalidationHandler* handler) = 0;
77 // Updates the set of ObjectIds associated with |handler|. |handler| must
78 // not be NULL, and must already be registered. An ID must be registered for
79 // at most one handler.
81 // Registered IDs are persisted across restarts of sync.
82 virtual void UpdateRegisteredInvalidationIds(
83 syncer::InvalidationHandler* handler,
84 const syncer::ObjectIdSet& ids) = 0;
86 // Stops sending notifications to |handler|. |handler| must not be NULL, and
87 // it must already be registered. Note that this doesn't unregister the IDs
88 // associated with |handler|.
90 // Handler registrations are persisted across restarts of sync.
91 virtual void UnregisterInvalidationHandler(
92 syncer::InvalidationHandler* handler) = 0;
94 // Returns the current invalidator state. When called from within
95 // InvalidationHandler::OnInvalidatorStateChange(), this must return
97 virtual syncer::InvalidatorState GetInvalidatorState() const = 0;
99 // Returns the ID belonging to this invalidation client. Can be used to
100 // prevent the receipt of notifications of our own changes.
101 virtual std::string GetInvalidatorClientId() const = 0;
103 // Return the logger used to debug invalidations
104 virtual InvalidationLogger* GetInvalidationLogger() = 0;
107 virtual ~InvalidationService() { }
110 } // namespace invalidation
112 #endif // CHROME_BROWSER_INVALIDATION_INVALIDATION_SERVICE_H_