net/base/sdch_observer.h

   1 // Copyright 2014 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 NET_BASE_SDCH_OBSERVER_H_
   6 #define NET_BASE_SDCH_OBSERVER_H_
   7
   8 #include <iosfwd>
   9 #include <string>
  10
  11 #include "net/base/net_export.h"
  12
  13 class GURL;
  14
  15 namespace net {
  16
  17 class SdchManager;
  18
  19 // Observer interface for SDCH.  Observers can register with
  20 // the SdchManager to receive notifications of various SDCH events.
  21 class NET_EXPORT SdchObserver {
  22  public:
  23   virtual ~SdchObserver();
  24
  25   // A dictionary has been added to the observed manager.
  26   virtual void OnDictionaryAdded(const GURL& dictionary_url,
  27                                  const std::string& server_hash) = 0;
  28
  29   // A dictionary has been removed from the observed manager. Note that this is
  30   // not called when dictionaries are cleared, so observers that want to track
  31   // the loaded dictionary set need to observe OnClearDictionaries as well.
  32   virtual void OnDictionaryRemoved(const std::string& server_hash) = 0;
  33
  34   // TODO(rdsmith): Add signal that an Avail-Dictionary header was generated.
  35   // Should be added if/when an observer wants to use it to fine-tune
  36   // dictionary deprecation (e.g. if Avail-Dictionary is generated and
  37   // the remote *doesn't* use it, that should deprecate the dictionary faster)
  38
  39   // A SDCH encoded response was received and the specified dictionary
  40   // was used to decode it.  This notification only occurs for successful
  41   // decodes.  Note that this notification may occur for dictionaries that
  42   // have been deleted from the SdchManager, since DictionarySets retain
  43   // references to deleted dictionaries.  Observers must handle this case.
  44   // TODO(rdsmith): Should this notification indicate how much
  45   // compression the dictionary provided?
  46   virtual void OnDictionaryUsed(const std::string& server_hash) = 0;
  47
  48   // A "Get-Dictionary" header has been seen.
  49   virtual void OnGetDictionary(const GURL& request_url,
  50                                const GURL& dictionary_url) = 0;
  51
  52   // Notification that SDCH has received a request to clear all
  53   // its dictionaries.
  54   virtual void OnClearDictionaries() = 0;
  55 };
  56
  57 }  // namespace net
  58
  59 #endif  // NET_BASE_SDCH_MANAGER_H_