1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
|
// 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.
#ifndef SYNC_API_ATTACHMENTS_ATTACHMENT_STORE_H_
#define SYNC_API_ATTACHMENTS_ATTACHMENT_STORE_H_
#include "base/callback.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_ptr.h"
#include "sync/api/attachments/attachment.h"
#include "sync/api/attachments/attachment_id.h"
#include "sync/base/sync_export.h"
namespace base {
class RefCountedMemory;
} // namespace base
namespace syncer {
class Attachment;
class AttachmentId;
// A place to locally store and access Attachments.
//
// Destroying this object does not necessarily cancel outstanding async
// operations. If you need cancel like semantics, use WeakPtr in the callbacks.
class SYNC_EXPORT AttachmentStore {
public:
AttachmentStore();
virtual ~AttachmentStore();
// TODO(maniscalco): Consider udpating Read and Write methods to support
// resumable transfers (bug 353292).
enum Result {
SUCCESS, // No error, all completed successfully.
UNSPECIFIED_ERROR, // An unspecified error occurred for one or more items.
};
typedef base::Callback<void(const Result&,
scoped_ptr<AttachmentMap>,
scoped_ptr<AttachmentIdList>)> ReadCallback;
typedef base::Callback<void(const Result&)> WriteCallback;
typedef base::Callback<void(const Result&)> DropCallback;
// Asynchronously reads the attachments identified by |ids|.
//
// |callback| will be invoked when finished. AttachmentStore will attempt to
// read all attachments specified in ids. If any of the attachments do not
// exist or could not be read, |callback|'s Result will be UNSPECIFIED_ERROR.
// Callback's AttachmentMap will contain all attachments that were
// successfully read, AttachmentIdList will contain attachment ids of
// attachments that are unavailable in attachment store, these need to be
// downloaded from server.
//
// Reads on individual attachments are treated atomically; |callback| will not
// read only part of an attachment.
virtual void Read(const AttachmentIdList& ids,
const ReadCallback& callback) = 0;
// Asynchronously writes |attachments| to the store.
//
// Will not overwrite stored attachments. Attempting to overwrite an
// attachment that already exists is not an error.
//
// |callback| will be invoked when finished. If any of the attachments could
// not be written |callback|'s Result will be UNSPECIFIED_ERROR. When this
// happens, some or none of the attachments may have been written
// successfully.
virtual void Write(const AttachmentList& attachments,
const WriteCallback& callback) = 0;
// Asynchronously drops |attchments| from this store.
//
// This does not remove attachments from the server.
//
// |callback| will be invoked when finished. Attempting to drop an attachment
// that does not exist is not an error. If any of the existing attachment
// could not be dropped, |callback|'s Result will be UNSPECIFIED_ERROR. When
// this happens, some or none of the attachments may have been dropped
// successfully.
virtual void Drop(const AttachmentIdList& ids,
const DropCallback& callback) = 0;
};
} // namespace syncer
#endif // SYNC_API_ATTACHMENTS_ATTACHMENT_STORE_H_
|
