osu/osu.Game/Stores/RealmFileStore.cs

117 lines
3.7 KiB
C#

// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.
using System;
using System.IO;
using System.Linq;
using osu.Framework.Extensions;
using osu.Framework.IO.Stores;
using osu.Framework.Logging;
using osu.Framework.Platform;
using osu.Framework.Testing;
using osu.Game.Database;
using osu.Game.Models;
using Realms;
#nullable enable
namespace osu.Game.Stores
{
/// <summary>
/// Handles the storing of files to the file system (and database) backing.
/// </summary>
[ExcludeFromDynamicCompile]
public class RealmFileStore
{
private readonly RealmContextFactory realmFactory;
public readonly IResourceStore<byte[]> Store;
public readonly Storage Storage;
public RealmFileStore(RealmContextFactory realmFactory, Storage storage)
{
this.realmFactory = realmFactory;
Storage = storage.GetStorageForDirectory(@"files");
Store = new StorageBackedResourceStore(Storage);
}
/// <summary>
/// Add a new file to the game-wide database, copying it to permanent storage if not already present.
/// </summary>
/// <param name="data">The file data stream.</param>
/// <param name="realm">The realm instance to add to. Should already be in a transaction.</param>
/// <returns></returns>
public RealmFile Add(Stream data, Realm realm)
{
string hash = data.ComputeSHA2Hash();
var existing = realm.Find<RealmFile>(hash);
var file = existing ?? new RealmFile { Hash = hash };
if (!checkFileExistsAndMatchesHash(file))
copyToStore(file, data);
if (!file.IsManaged)
realm.Add(file);
return file;
}
private void copyToStore(RealmFile file, Stream data)
{
data.Seek(0, SeekOrigin.Begin);
using (var output = Storage.GetStream(file.StoragePath, FileAccess.Write))
data.CopyTo(output);
data.Seek(0, SeekOrigin.Begin);
}
private bool checkFileExistsAndMatchesHash(RealmFile file)
{
string path = file.StoragePath;
// we may be re-adding a file to fix missing store entries.
if (!Storage.Exists(path))
return false;
// even if the file already exists, check the existing checksum for safety.
using (var stream = Storage.GetStream(path))
return stream.ComputeSHA2Hash() == file.Hash;
}
public void Cleanup()
{
var realm = realmFactory.Context;
// can potentially be run asynchronously, although we will need to consider operation order for disk deletion vs realm removal.
using (var transaction = realm.BeginWrite())
{
// TODO: consider using a realm native query to avoid iterating all files (https://github.com/realm/realm-dotnet/issues/2659#issuecomment-927823707)
var files = realm.All<RealmFile>().ToList();
foreach (var file in files)
{
if (file.BacklinksCount > 0)
continue;
try
{
Storage.Delete(file.StoragePath);
realm.Remove(file);
}
catch (Exception e)
{
Logger.Error(e, $@"Could not delete databased file {file.Hash}");
}
}
transaction.Commit();
}
}
}
}