components/sync_driver/backend_data_type_configurer.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 COMPONENTS_SYNC_DRIVER_BACKEND_DATA_TYPE_CONFIGURER_H_
   6 #define COMPONENTS_SYNC_DRIVER_BACKEND_DATA_TYPE_CONFIGURER_H_
   7
   8 #include <map>
   9
  10 #include "base/callback.h"
  11 #include "sync/internal_api/public/base/model_type.h"
  12 #include "sync/internal_api/public/configure_reason.h"
  13 #include "sync/internal_api/public/engine/model_safe_worker.h"
  14
  15 namespace sync_driver {
  16
  17 class ChangeProcessor;
  18
  19 // The DataTypeConfigurer interface abstracts out the action of
  20 // configuring a set of new data types and cleaning up after a set of
  21 // removed data types.
  22 class BackendDataTypeConfigurer {
  23  public:
  24   enum DataTypeConfigState {
  25     CONFIGURE_ACTIVE,     // Actively being configured. Data of such types
  26                           // will be downloaded if not present locally.
  27     CONFIGURE_INACTIVE,   // Already configured or to be configured in future.
  28                           // Data of such types is left as it is, no
  29                           // downloading or purging.
  30     CONFIGURE_CLEAN,      // Actively being configured but requiring unapply
  31                           // and GetUpdates first (e.g. for persistence errors).
  32     DISABLED,             // Not syncing. Disabled by user.
  33     FATAL,                // Not syncing due to unrecoverable error.
  34     CRYPTO,               // Not syncing due to a cryptographer error.
  35     UNREADY,              // Not syncing due to transient error.
  36   };
  37   typedef std::map<syncer::ModelType, DataTypeConfigState>
  38       DataTypeConfigStateMap;
  39
  40   // Configures sync for data types in config_state_map according to the states.
  41   // |ready_task| is called on the same thread as ConfigureDataTypes
  42   // is called when configuration is done with the set of data types
  43   // that succeeded/failed configuration (i.e., configuration succeeded iff
  44   // the failed set is empty).
  45   // Returns: the set of types that are already configured and are ready to
  46   // start.
  47   //
  48   // TODO(akalin): Use a Delegate class with
  49   // OnConfigureSuccess/OnConfigureFailure/OnConfigureRetry instead of
  50   // a pair of callbacks.  The awkward part is handling when
  51   // SyncBackendHost calls ConfigureDataTypes on itself to configure
  52   // Nigori.
  53   virtual syncer::ModelTypeSet ConfigureDataTypes(
  54       syncer::ConfigureReason reason,
  55       const DataTypeConfigStateMap& config_state_map,
  56       const base::Callback<void(syncer::ModelTypeSet, syncer::ModelTypeSet)>&
  57           ready_task,
  58       const base::Callback<void()>& retry_callback) = 0;
  59
  60   // Return model types in |state_map| that match |state|.
  61   static syncer::ModelTypeSet GetDataTypesInState(
  62       DataTypeConfigState state, const DataTypeConfigStateMap& state_map);
  63
  64   // Activates change processing for the given data type.  This must
  65   // be called synchronously with the data type's model association so
  66   // no changes are dropped between model association and change
  67   // processor activation.
  68   virtual void ActivateDataType(
  69       syncer::ModelType type, syncer::ModelSafeGroup group,
  70       ChangeProcessor* change_processor) = 0;
  71
  72   // Deactivates change processing for the given data type.
  73   virtual void DeactivateDataType(syncer::ModelType type) = 0;
  74
  75   // Set state of |types| in |state_map| to |state|.
  76   static void SetDataTypesState(DataTypeConfigState state,
  77                                 syncer::ModelTypeSet types,
  78                                 DataTypeConfigStateMap* state_map);
  79
  80  protected:
  81   virtual ~BackendDataTypeConfigurer() {}
  82 };
  83
  84 }  // namespace sync_driver
  85
  86 #endif  // COMPONENTS_SYNC_DRIVER_BACKEND_DATA_TYPE_CONFIGURER_H_