data_type_worker.h | Explore in Territory

// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_SYNC_ENGINE_DATA_TYPE_WORKER_H_
#define COMPONENTS_SYNC_ENGINE_DATA_TYPE_WORKER_H_

#include <stddef.h>

#include <map>
#include <memory>
#include <string>
#include <vector>

#include "base/memory/raw_ptr.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/sequence_checker.h"
#include "base/synchronization/waitable_event.h"
#include "components/sync/base/data_type.h"
#include "components/sync/base/passphrase_enums.h"
#include "components/sync/engine/cancelation_signal.h"
#include "components/sync/engine/commit_and_get_updates_types.h"
#include "components/sync/engine/commit_contributor.h"
#include "components/sync/engine/commit_queue.h"
#include "components/sync/engine/nigori/cryptographer.h"
#include "components/sync/engine/nudge_handler.h"
#include "components/sync/engine/sync_encryption_handler.h"
#include "components/sync/engine/update_handler.h"
#include "components/sync/protocol/data_type_state.pb.h"

namespace sync_pb {
class DataTypeContext;
class DataTypeProgressMarker;
class DataTypeState;
class GarbageCollectionDirective;
class GetUpdateTriggers;
class SyncEntity;
}  // namespace sync_pb

namespace syncer {

class CancelationSignal;
class DataTypeProcessor;

// These values are persisted to logs. Entries should not be renumbered and
// numeric values should never be reused.
// LINT.IfChange(SyncPasswordNotesStateInUpdate)
enum class PasswordNotesStateForUMA { … };
// LINT.ThenChange(/tools/metrics/histograms/metadata/sync/enums.xml:SyncPasswordNotesStateInUpdate)

// These values are persisted to logs. Entries should not be renumbered and
// numeric values should never be reused.
// LINT.IfChange(PendingInvalidationStatus)
enum class PendingInvalidationStatus { … };
// LINT.ThenChange(/tools/metrics/histograms/metadata/sync/enums.xml:PendingInvalidationStatus)

// A smart cache for sync types to communicate with the sync sequence.
//
// When the sync data type wants to talk to the sync server, it will
// send a message from its sequence to this object on the sync sequence. This
// object ensures the appropriate sync server communication gets scheduled and
// executed. The response, if any, will be returned to the data types's sequence
// eventually.
//
// This object also has a role to play in communications in the opposite
// direction. Sometimes the sync sequence will receive changes from the sync
// server and deliver them here. This object will post this information back to
// the appropriate component on the data type's sequence.
//
// This object does more than just pass along messages. It understands the sync
// protocol, and it can make decisions when it sees conflicting messages. For
// example, if the sync server sends down an update for a sync entity that is
// currently pending for commit, this object will detect this condition and
// cancel the pending commit.
//
// Lives on the sync sequence.
class DataTypeWorker : public UpdateHandler,
                        public CommitContributor,
                        public CommitQueue { … };

// GetLocalChangesRequest is a container for GetLocalChanges call response. It
// allows sync sequence to block waiting for model sequence to call SetResponse.
// This class supports canceling blocking call through CancelationSignal during
// sync engine shutdown.
//
// It should be used in the following manner:
// scoped_refptr<GetLocalChangesRequest> request =
//     base::MakeRefCounted<GetLocalChangesRequest>(cancelation_signal_);
// data_type_processor_->GetLocalChanges(
//     max_entries,
//     base::BindOnce(&GetLocalChangesRequest::SetResponse, request));
// request->WaitForResponseOrCancelation();
// CommitRequestDataList response;
// if (!request->WasCancelled())
//   response = request->ExtractResponse();
class GetLocalChangesRequest
    : public base::RefCountedThreadSafe<GetLocalChangesRequest>,
      public CancelationSignal::Observer { … };

}  // namespace syncer

#endif  // COMPONENTS_SYNC_ENGINE_DATA_TYPE_WORKER_H_
chromium/components/sync/engine/data_type_worker.h
