blob: 005ad23c37c18a837830469bb443e5acd5b7b9a4 (
plain)
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
|
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace Timeline.Services
{
public class DataEntry
{
#pragma warning disable CA1819 // Properties should not return arrays
public byte[] Data { get; set; } = default!;
#pragma warning restore CA1819 // Properties should not return arrays
public DataInfo Info { get; set; } = default!;
}
public class DataInfo
{
public DateTime Time { get; set; }
public string Type { get; set; } = default!;
}
/// <summary>
/// A data manager controling data.
/// </summary>
/// <remarks>
/// All data to be saved will be checked identity.
/// Identical data will be saved as one copy and return the same tag.
/// Every data has a ref count. When data is saved, ref count increase.
/// When data is removed, ref count decease. If ref count is decreased
/// to 0, the data entry will be destroyed and no longer occupy space.
///
/// Type is just an attached attribute for convenience and not participate
/// in identity verification. This should be only used to save blobs but not
/// strings. It will be rare for identity blob with different type, I think.
/// </remarks>
public interface IDataManager
{
/// <summary>
/// Saves the data to a new entry if it does not exist,
/// increases its ref count and returns a tag to the entry.
/// </summary>
/// <param name="data">The data. Can't be null.</param>
/// <param name="type">The type of the data. Can't be null.</param>
/// <returns>The tag of the created entry.</returns>
/// <exception cref="ArgumentNullException">Thrown when <paramref name="data"/> or <paramref name="type"/> is null.</exception>
/// <exception cref="InvalidOperationException">Thrown when a saved copy of data already exists but type is different.</exception>
public Task<string> RetainEntry(byte[] data, string type);
/// <summary>
/// Decrease the the ref count of the entry.
/// Remove it if ref count is zero.
/// </summary>
/// <param name="tag">The tag of the entry.</param>
/// <exception cref="ArgumentNullException">Thrown when <paramref name="tag"/> is null.</exception>
/// <remarks>
/// It's no-op if entry with tag does not exist.
/// </remarks>
public Task FreeEntry(string tag);
/// <summary>
/// Retrieve the entry with given tag.
/// </summary>
/// <param name="tag">The tag of the entry.</param>
/// <returns>The entry.</returns>
/// <exception cref="ArgumentNullException">Thrown when <paramref name="tag"/> is null.</exception>
/// <exception cref="InvalidOperationException">Thrown when entry with given tag does not exist.</exception>
public Task<DataEntry> GetEntry(string tag);
/// <summary>
/// Retrieve info of the entry with given tag.
/// </summary>
/// <param name="tag">The tag of the entry.</param>
/// <returns>The entry info.</returns>
/// <exception cref="ArgumentNullException">Thrown when <paramref name="tag"/> is null.</exception>
/// <exception cref="InvalidOperationException">Thrown when entry with given tag does not exist.</exception>
public Task<DataInfo> GetEntryInfo(string tag);
}
}
|
