components/sync_driver/model_associator.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_MODEL_ASSOCIATOR_H_
   6 #define COMPONENTS_SYNC_DRIVER_MODEL_ASSOCIATOR_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/synchronization/lock.h"
  10 #include "sync/api/sync_error.h"
  11 #include "sync/internal_api/public/base/model_type.h"
  12
  13 namespace syncer {
  14 class BaseNode;
  15 class SyncMergeResult;
  16 }
  17
  18 namespace sync_driver {
  19
  20 // This represents the fundamental operations used for model association that
  21 // are common to all ModelAssociators and do not depend on types of the models
  22 // being associated.
  23 class AssociatorInterface {
  24  public:
  25   virtual ~AssociatorInterface() {}
  26
  27   // Iterates through both the sync and the chrome model looking for
  28   // matched pairs of items. After successful completion, the models
  29   // should be identical and corresponding. Returns true on
  30   // success. On failure of this step, we should abort the sync
  31   // operation and report an error to the user.
  32   virtual syncer::SyncError AssociateModels(
  33       syncer::SyncMergeResult* local_merge_result,
  34       syncer::SyncMergeResult* syncer_merge_result) = 0;
  35
  36   // Clears all the associations between the chrome and sync models.
  37   virtual syncer::SyncError DisassociateModels() = 0;
  38
  39   // The has_nodes out parameter is set to true if the sync model has
  40   // nodes other than the permanent tagged nodes.  The method may
  41   // return false if an error occurred.
  42   virtual bool SyncModelHasUserCreatedNodes(bool* has_nodes) = 0;
  43
  44   // Calling this method while AssociateModels() is in progress will
  45   // cause the method to exit early with a "false" return value.  This
  46   // is useful for aborting model associations for shutdown.  This
  47   // method is only implemented for model associators that are invoked
  48   // off the main thread.
  49   virtual void AbortAssociation() = 0;
  50
  51   // Returns whether the datatype is ready for encryption/decryption if the
  52   // sync service requires it.
  53   // TODO(zea): This should be implemented automatically for each datatype, see
  54   // http://crbug.com/76232.
  55   virtual bool CryptoReadyIfNecessary() = 0;
  56 };
  57
  58 // In addition to the generic methods, association can refer to operations
  59 // that depend on the types of the actual IDs we are associating and the
  60 // underlying node type in the browser.  We collect these into a templatized
  61 // interface that encapsulates everything you need to implement to have a model
  62 // associator for a specific data type.
  63 // This template is appropriate for data types where a Node* makes sense for
  64 // referring to a particular item.  If we encounter a type that does not fit
  65 // in this world, we may want to have several PerDataType templates.
  66 template <class Node, class IDType>
  67 class PerDataTypeAssociatorInterface : public AssociatorInterface {
  68  public:
  69   virtual ~PerDataTypeAssociatorInterface() {}
  70   // Returns sync id for the given chrome model id.
  71   // Returns syncer::kInvalidId if the sync node is not found for the given
  72   // chrome id.
  73   virtual int64 GetSyncIdFromChromeId(const IDType& id) = 0;
  74
  75   // Returns the chrome node for the given sync id.
  76   // Returns NULL if no node is found for the given sync id.
  77   virtual const Node* GetChromeNodeFromSyncId(int64 sync_id) = 0;
  78
  79   // Initializes the given sync node from the given chrome node id.
  80   // Returns false if no sync node was found for the given chrome node id or
  81   // if the initialization of sync node fails.
  82   virtual bool InitSyncNodeFromChromeId(
  83       const IDType& node_id,
  84       syncer::BaseNode* sync_node) = 0;
  85
  86   // Associates the given chrome node with the given sync id.
  87   virtual void Associate(const Node* node, int64 sync_id) = 0;
  88
  89   // Remove the association that corresponds to the given sync id.
  90   virtual void Disassociate(int64 sync_id) = 0;
  91 };
  92
  93 }  // namespace sync_driver
  94
  95 #endif  // COMPONENTS_SYNC_DRIVER_MODEL_ASSOCIATOR_H_