blob: 8481749f931e565691ba8b25b6181d8566c0acd7 [file] [log] [blame]
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <stdint.h>
#include <string>
namespace syncer {
// An interface that wraps sync's interactions with the component that provides
// it with invalidations.
class InvalidationInterface {
// Orders invalidations based on version number and IsUnknownVersion().
static bool LessThanByVersion(const InvalidationInterface& a,
const InvalidationInterface& b);
virtual ~InvalidationInterface();
// Returns true if this is an 'unknown version' invalidation.
// Such invalidations have no valid payload or version number.
virtual bool IsUnknownVersion() const = 0;
// Returns the payload of this item.
// DCHECKs if this is an unknown version invalidation.
virtual const std::string& GetPayload() const = 0;
// Retursn the version of this item.
// DCHECKs if this is an unknown version invalidation.
// It is preferable to use the LessThan() function, which handles unknown
// versions properly, rather than this function.
virtual int64_t GetVersion() const = 0;
// This function will be called when the invalidation has been handled
// successfully.
virtual void Acknowledge() = 0;
// This function should be called if a lack of buffer space required that we
// drop this invalidation.
// To indicate recovery from a drop event, the receiver of this invalidation
// will call Acknowledge() on the most recently dropped invalidation.
virtual void Drop() = 0;
} // namespace syncer